platform/kernel/linux-rpi.git
5 years agofbdev: fix WARNING in __alloc_pages_nodemask bug
Jiufei Xue [Thu, 11 Apr 2019 17:25:12 +0000 (19:25 +0200)]
fbdev: fix WARNING in __alloc_pages_nodemask bug

commit 8c40292be9169a9cbe19aadd1a6fc60cbd1af82f upstream.

Syzkaller hit 'WARNING in __alloc_pages_nodemask' bug.

WARNING: CPU: 1 PID: 1473 at mm/page_alloc.c:4377
__alloc_pages_nodemask+0x4da/0x2130
Kernel panic - not syncing: panic_on_warn set ...

Call Trace:
 alloc_pages_current+0xb1/0x1e0
 kmalloc_order+0x1f/0x60
 kmalloc_order_trace+0x1d/0x120
 fb_alloc_cmap_gfp+0x85/0x2b0
 fb_set_user_cmap+0xff/0x370
 do_fb_ioctl+0x949/0xa20
 fb_ioctl+0xdd/0x120
 do_vfs_ioctl+0x186/0x1070
 ksys_ioctl+0x89/0xa0
 __x64_sys_ioctl+0x74/0xb0
 do_syscall_64+0xc8/0x550
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

This is a warning about order >= MAX_ORDER and the order is from
userspace ioctl. Add flag __NOWARN to silence this warning.

Signed-off-by: Jiufei Xue <jiufei.xue@linux.alibaba.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
5 years agoovl: relax WARN_ON() for overlapping layers use case
Amir Goldstein [Thu, 28 Mar 2019 15:38:29 +0000 (17:38 +0200)]
ovl: relax WARN_ON() for overlapping layers use case

commit acf3062a7e1ccf67c6f7e7c28671a6708fde63b0 upstream.

This nasty little syzbot repro:
https://syzkaller.appspot.com/x/repro.syz?x=12c7a94f400000

Creates overlay mounts where the same directory is both in upper and lower
layers. Simplified example:

  mkdir foo work
  mount -t overlay none foo -o"lowerdir=.,upperdir=foo,workdir=work"

The repro runs several threads in parallel that attempt to chdir into foo
and attempt to symlink/rename/exec/mkdir the file bar.

The repro hits a WARN_ON() I placed in ovl_instantiate(), which suggests
that an overlay inode already exists in cache and is hashed by the pointer
of the real upper dentry that ovl_create_real() has just created. At the
point of the WARN_ON(), for overlay dir inode lock is held and upper dir
inode lock, so at first, I did not see how this was possible.

On a closer look, I see that after ovl_create_real(), because of the
overlapping upper and lower layers, a lookup by another thread can find the
file foo/bar that was just created in upper layer, at overlay path
foo/foo/bar and hash the an overlay inode with the new real dentry as lower
dentry. This is possible because the overlay directory foo/foo is not
locked and the upper dentry foo/bar is in dcache, so ovl_lookup() can find
it without taking upper dir inode shared lock.

Overlapping layers is considered a wrong setup which would result in
unexpected behavior, but it shouldn't crash the kernel and it shouldn't
trigger WARN_ON() either, so relax this WARN_ON() and leave a pr_warn()
instead to cover all cases of failure to get an overlay inode.

The error returned from failure to insert new inode to cache with
inode_insert5() was changed to -EEXIST, to distinguish from the error
-ENOMEM returned on failure to get/allocate inode with iget5_locked().

Reported-by: syzbot+9c69c282adc4edd2b540@syzkaller.appspotmail.com
Fixes: 01b39dcc9568 ("ovl: use inode_insert5() to hash a newly...")
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
5 years agobtrfs: honor path->skip_locking in backref code
Josef Bacik [Wed, 16 Jan 2019 16:00:57 +0000 (11:00 -0500)]
btrfs: honor path->skip_locking in backref code

commit 38e3eebff643db725633657d1d87a3be019d1018 upstream.

Qgroups will do the old roots lookup at delayed ref time, which could be
while walking down the extent root while running a delayed ref.  This
should be fine, except we specifically lock eb's in the backref walking
code irrespective of path->skip_locking, which deadlocks the system.
Fix up the backref code to honor path->skip_locking, nobody will be
modifying the commit_root when we're searching so it's completely safe
to do.

This happens since fb235dc06fac ("btrfs: qgroup: Move half of the qgroup
accounting time out of commit trans"), kernel may lockup with quota
enabled.

There is one backref trace triggered by snapshot dropping along with
write operation in the source subvolume.  The example can be reliably
reproduced:

  btrfs-cleaner   D    0  4062      2 0x80000000
  Call Trace:
   schedule+0x32/0x90
   btrfs_tree_read_lock+0x93/0x130 [btrfs]
   find_parent_nodes+0x29b/0x1170 [btrfs]
   btrfs_find_all_roots_safe+0xa8/0x120 [btrfs]
   btrfs_find_all_roots+0x57/0x70 [btrfs]
   btrfs_qgroup_trace_extent_post+0x37/0x70 [btrfs]
   btrfs_qgroup_trace_leaf_items+0x10b/0x140 [btrfs]
   btrfs_qgroup_trace_subtree+0xc8/0xe0 [btrfs]
   do_walk_down+0x541/0x5e3 [btrfs]
   walk_down_tree+0xab/0xe7 [btrfs]
   btrfs_drop_snapshot+0x356/0x71a [btrfs]
   btrfs_clean_one_deleted_snapshot+0xb8/0xf0 [btrfs]
   cleaner_kthread+0x12b/0x160 [btrfs]
   kthread+0x112/0x130
   ret_from_fork+0x27/0x50

When dropping snapshots with qgroup enabled, we will trigger backref
walk.

However such backref walk at that timing is pretty dangerous, as if one
of the parent nodes get WRITE locked by other thread, we could cause a
dead lock.

For example:

           FS 260     FS 261 (Dropped)
            node A        node B
           /      \      /      \
       node C      node D      node E
      /   \         /  \        /     \
  leaf F|leaf G|leaf H|leaf I|leaf J|leaf K

The lock sequence would be:

      Thread A (cleaner)             |       Thread B (other writer)
-----------------------------------------------------------------------
write_lock(B)                        |
write_lock(D)                        |
^^^ called by walk_down_tree()       |
                                     |       write_lock(A)
                                     |       write_lock(D) << Stall
read_lock(H) << for backref walk     |
read_lock(D) << lock owner is        |
                the same thread A    |
                so read lock is OK   |
read_lock(A) << Stall                |

So thread A hold write lock D, and needs read lock A to unlock.
While thread B holds write lock A, while needs lock D to unlock.

This will cause a deadlock.

This is not only limited to snapshot dropping case.  As the backref
walk, even only happens on commit trees, is breaking the normal top-down
locking order, makes it deadlock prone.

Fixes: fb235dc06fac ("btrfs: qgroup: Move half of the qgroup accounting time out of commit trans")
CC: stable@vger.kernel.org # 4.14+
Reported-and-tested-by: David Sterba <dsterba@suse.com>
Reported-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: Filipe Manana <fdmanana@suse.com>
[ rebase to latest branch and fix lock assert bug in btrfs/007 ]
[ backport to linux-4.19.y branch, solve minor conflicts ]
Signed-off-by: Qu Wenruo <wqu@suse.com>
[ copy logs and deadlock analysis from Qu's patch ]
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
5 years agoarm64: errata: Add workaround for Cortex-A76 erratum #1463225
Will Deacon [Mon, 29 Apr 2019 12:03:57 +0000 (13:03 +0100)]
arm64: errata: Add workaround for Cortex-A76 erratum #1463225

commit 969f5ea627570e91c9d54403287ee3ed657f58fe upstream.

Revisions of the Cortex-A76 CPU prior to r4p0 are affected by an erratum
that can prevent interrupts from being taken when single-stepping.

This patch implements a software workaround to prevent userspace from
effectively being able to disable interrupts.

Cc: <stable@vger.kernel.org>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
5 years agobrcmfmac: add subtype check for event handling in data path
Arend van Spriel [Thu, 14 Feb 2019 12:43:48 +0000 (13:43 +0100)]
brcmfmac: add subtype check for event handling in data path

commit a4176ec356c73a46c07c181c6d04039fafa34a9f upstream.

For USB there is no separate channel being used to pass events
from firmware to the host driver and as such are passed over the
data path. In order to detect mock event messages an additional
check is needed on event subtype. This check is added conditionally
using unlikely() keyword.

Reviewed-by: Hante Meuleman <hante.meuleman@broadcom.com>
Reviewed-by: Pieter-Paul Giesberts <pieter-paul.giesberts@broadcom.com>
Reviewed-by: Franky Lin <franky.lin@broadcom.com>
Signed-off-by: Arend van Spriel <arend.vanspriel@broadcom.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Cc: Ben Hutchings <ben.hutchings@codethink.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
5 years agobrcmfmac: assure SSID length from firmware is limited
Arend van Spriel [Thu, 14 Feb 2019 12:43:47 +0000 (13:43 +0100)]
brcmfmac: assure SSID length from firmware is limited

commit 1b5e2423164b3670e8bc9174e4762d297990deff upstream.

The SSID length as received from firmware should not exceed
IEEE80211_MAX_SSID_LEN as that would result in heap overflow.

Reviewed-by: Hante Meuleman <hante.meuleman@broadcom.com>
Reviewed-by: Pieter-Paul Giesberts <pieter-paul.giesberts@broadcom.com>
Reviewed-by: Franky Lin <franky.lin@broadcom.com>
Signed-off-by: Arend van Spriel <arend.vanspriel@broadcom.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Cc: Ben Hutchings <ben.hutchings@codethink.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
5 years agobpf: add bpf_jit_limit knob to restrict unpriv allocations
Daniel Borkmann [Mon, 22 Oct 2018 23:11:04 +0000 (01:11 +0200)]
bpf: add bpf_jit_limit knob to restrict unpriv allocations

commit ede95a63b5e84ddeea6b0c473b36ab8bfd8c6ce3 upstream.

Rick reported that the BPF JIT could potentially fill the entire module
space with BPF programs from unprivileged users which would prevent later
attempts to load normal kernel modules or privileged BPF programs, for
example. If JIT was enabled but unsuccessful to generate the image, then
before commit 290af86629b2 ("bpf: introduce BPF_JIT_ALWAYS_ON config")
we would always fall back to the BPF interpreter. Nowadays in the case
where the CONFIG_BPF_JIT_ALWAYS_ON could be set, then the load will abort
with a failure since the BPF interpreter was compiled out.

Add a global limit and enforce it for unprivileged users such that in case
of BPF interpreter compiled out we fail once the limit has been reached
or we fall back to BPF interpreter earlier w/o using module mem if latter
was compiled in. In a next step, fair share among unprivileged users can
be resolved in particular for the case where we would fail hard once limit
is reached.

Fixes: 290af86629b2 ("bpf: introduce BPF_JIT_ALWAYS_ON config")
Fixes: 0a14842f5a3c ("net: filter: Just In Time compiler for x86-64")
Co-Developed-by: Rick Edgecombe <rick.p.edgecombe@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Jann Horn <jannh@google.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: LKML <linux-kernel@vger.kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Cc: Ben Hutchings <ben.hutchings@codethink.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
5 years agoNFSv4.1 fix incorrect return value in copy_file_range
Olga Kornievskaia [Thu, 11 Apr 2019 18:34:18 +0000 (14:34 -0400)]
NFSv4.1 fix incorrect return value in copy_file_range

commit 0769663b4f580566ef6cdf366f3073dbe8022c39 upstream.

According to the NFSv4.2 spec if the input and output file is the
same file, operation should fail with EINVAL. However, linux
copy_file_range() system call has no such restrictions. Therefore,
in such case let's return EOPNOTSUPP and allow VFS to fallback
to doing do_splice_direct(). Also when copy_file_range is called
on an NFSv4.0 or 4.1 mount (ie., a server that doesn't support
COPY functionality), we also need to return EOPNOTSUPP and
fallback to a regular copy.

Fixes xfstest generic/075, generic/091, generic/112, generic/263
for all NFSv4.x versions.

Signed-off-by: Olga Kornievskaia <kolga@netapp.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Cc: Yu Xu <xuyu@linux.alibaba.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
5 years agoNFSv4.2 fix unnecessary retry in nfs4_copy_file_range
Olga Kornievskaia [Sat, 12 Jan 2019 00:04:44 +0000 (19:04 -0500)]
NFSv4.2 fix unnecessary retry in nfs4_copy_file_range

commit 45ac486ecf2dc998e25cf32f0cabf2deaad875be upstream.

Currently nfs42_proc_copy_file_range() can not return EAGAIN.

Fixes: e4648aa4f98a ("NFS recover from destination server reboot for copies")
Signed-off-by: Olga Kornievskaia <kolga@netapp.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Cc: Yu Xu <xuyu@linux.alibaba.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
5 years agofbdev: fix divide error in fb_var_to_videomode
Shile Zhang [Mon, 1 Apr 2019 15:47:00 +0000 (17:47 +0200)]
fbdev: fix divide error in fb_var_to_videomode

commit cf84807f6dd0be5214378e66460cfc9187f532f9 upstream.

To fix following divide-by-zero error found by Syzkaller:

  divide error: 0000 [#1] SMP PTI
  CPU: 7 PID: 8447 Comm: test Kdump: loaded Not tainted 4.19.24-8.al7.x86_64 #1
  Hardware name: Alibaba Cloud Alibaba Cloud ECS, BIOS rel-1.12.0-0-ga698c8995f-prebuilt.qemu.org 04/01/2014
  RIP: 0010:fb_var_to_videomode+0xae/0xc0
  Code: 04 44 03 46 78 03 4e 7c 44 03 46 68 03 4e 70 89 ce d1 ee 69 c0 e8 03 00 00 f6 c2 01 0f 45 ce 83 e2 02 8d 34 09 0f 45 ce 31 d2 <41> f7 f0 31 d2 f7 f1 89 47 08 f3 c3 66 0f 1f 44 00 00 0f 1f 44 00
  RSP: 0018:ffffb7e189347bf0 EFLAGS: 00010246
  RAX: 00000000e1692410 RBX: ffffb7e189347d60 RCX: 0000000000000000
  RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffb7e189347c10
  RBP: ffff99972a091c00 R08: 0000000000000000 R09: 0000000000000000
  R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000100
  R13: 0000000000010000 R14: 00007ffd66baf6d0 R15: 0000000000000000
  FS:  00007f2054d11740(0000) GS:ffff99972fbc0000(0000) knlGS:0000000000000000
  CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  CR2: 00007f205481fd20 CR3: 00000004288a0001 CR4: 00000000001606a0
  Call Trace:
   fb_set_var+0x257/0x390
   ? lookup_fast+0xbb/0x2b0
   ? fb_open+0xc0/0x140
   ? chrdev_open+0xa6/0x1a0
   do_fb_ioctl+0x445/0x5a0
   do_vfs_ioctl+0x92/0x5f0
   ? __alloc_fd+0x3d/0x160
   ksys_ioctl+0x60/0x90
   __x64_sys_ioctl+0x16/0x20
   do_syscall_64+0x5b/0x190
   entry_SYSCALL_64_after_hwframe+0x44/0xa9
  RIP: 0033:0x7f20548258d7
  Code: 44 00 00 48 8b 05 b9 15 2d 00 64 c7 00 26 00 00 00 48 c7 c0 ff ff ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 b8 10 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d 89 15 2d 00 f7 d8 64 89 01 48

It can be triggered easily with following test code:

  #include <linux/fb.h>
  #include <fcntl.h>
  #include <sys/ioctl.h>
  int main(void)
  {
          struct fb_var_screeninfo var = {.activate = 0x100, .pixclock = 60};
          int fd = open("/dev/fb0", O_RDWR);
          if (fd < 0)
                  return 1;

          if (ioctl(fd, FBIOPUT_VSCREENINFO, &var))
                  return 1;

          return 0;
  }

Signed-off-by: Shile Zhang <shile.zhang@linux.alibaba.com>
Cc: Fredrik Noring <noring@nocrew.org>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Reviewed-by: Mukesh Ojha <mojha@codeaurora.org>
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
5 years agoudlfb: fix some inconsistent NULL checking
Dan Carpenter [Thu, 20 Dec 2018 18:13:07 +0000 (19:13 +0100)]
udlfb: fix some inconsistent NULL checking

commit c143a559b073aeea688b9bb7c5b46f3cf322d569 upstream.

In the current kernel, then kzalloc() can't fail for small allocations,
but if it did fail then we would have a NULL dereference in the error
handling.  Also in dlfb_usb_disconnect() if "info" were NULL then it
would cause an Oops inside the unregister_framebuffer() function but it
can't be NULL so let's remove that check.

Fixes: 68a958a915ca ("udlfb: handle unplug properly")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Cc: Bernie Thompson <bernie@plugable.com>
Cc: Mikulas Patocka <mpatocka@redhat.com>
Cc: Alexey Khoroshilov <khoroshilov@ispras.ru>
Cc: Colin Ian King <colin.king@canonical.com>
Cc: Wen Yang <wen.yang99@zte.com.cn>
[b.zolnierkie: added "Fixes:" tag]
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
5 years agobtrfs: sysfs: don't leak memory when failing add fsid
Tobin C. Harding [Mon, 13 May 2019 03:39:12 +0000 (13:39 +1000)]
btrfs: sysfs: don't leak memory when failing add fsid

commit e32773357d5cc271b1d23550b3ed026eb5c2a468 upstream.

A failed call to kobject_init_and_add() must be followed by a call to
kobject_put().  Currently in the error path when adding fs_devices we
are missing this call.  This could be fixed by calling
btrfs_sysfs_remove_fsid() if btrfs_sysfs_add_fsid() returns an error or
by adding a call to kobject_put() directly in btrfs_sysfs_add_fsid().
Here we choose the second option because it prevents the slightly
unusual error path handling requirements of kobject from leaking out
into btrfs functions.

Add a call to kobject_put() in the error path of kobject_add_and_init().
This causes the release method to be called if kobject_init_and_add()
fails.  open_tree() is the function that calls btrfs_sysfs_add_fsid()
and the error code in this function is already written with the
assumption that the release method is called during the error path of
open_tree() (as seen by the call to btrfs_sysfs_remove_fsid() under the
fail_fsdev_sysfs label).

Cc: stable@vger.kernel.org # v4.4+
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Tobin C. Harding <tobin@kernel.org>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
5 years agobtrfs: sysfs: Fix error path kobject memory leak
Tobin C. Harding [Mon, 13 May 2019 03:39:11 +0000 (13:39 +1000)]
btrfs: sysfs: Fix error path kobject memory leak

commit 450ff8348808a89cc27436771aa05c2b90c0eef1 upstream.

If a call to kobject_init_and_add() fails we must call kobject_put()
otherwise we leak memory.

Calling kobject_put() when kobject_init_and_add() fails drops the
refcount back to 0 and calls the ktype release method (which in turn
calls the percpu destroy and kfree).

Add call to kobject_put() in the error path of call to
kobject_init_and_add().

Cc: stable@vger.kernel.org # v4.4+
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Tobin C. Harding <tobin@kernel.org>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
5 years agoBtrfs: fix race between ranged fsync and writeback of adjacent ranges
Filipe Manana [Mon, 6 May 2019 15:44:02 +0000 (16:44 +0100)]
Btrfs: fix race between ranged fsync and writeback of adjacent ranges

commit 0c713cbab6200b0ab6473b50435e450a6e1de85d upstream.

When we do a full fsync (the bit BTRFS_INODE_NEEDS_FULL_SYNC is set in the
inode) that happens to be ranged, which happens during a msync() or writes
for files opened with O_SYNC for example, we can end up with a corrupt log,
due to different file extent items representing ranges that overlap with
each other, or hit some assertion failures.

When doing a ranged fsync we only flush delalloc and wait for ordered
exents within that range. If while we are logging items from our inode
ordered extents for adjacent ranges complete, we end up in a race that can
make us insert the file extent items that overlap with others we logged
previously and the assertion failures.

For example, if tree-log.c:copy_items() receives a leaf that has the
following file extents items, all with a length of 4K and therefore there
is an implicit hole in the range 68K to 72K - 1:

  (257 EXTENT_ITEM 64K), (257 EXTENT_ITEM 72K), (257 EXTENT_ITEM 76K), ...

It copies them to the log tree. However due to the need to detect implicit
holes, it may release the path, in order to look at the previous leaf to
detect an implicit hole, and then later it will search again in the tree
for the first file extent item key, with the goal of locking again the
leaf (which might have changed due to concurrent changes to other inodes).

However when it locks again the leaf containing the first key, the key
corresponding to the extent at offset 72K may not be there anymore since
there is an ordered extent for that range that is finishing (that is,
somewhere in the middle of btrfs_finish_ordered_io()), and it just
removed the file extent item but has not yet replaced it with a new file
extent item, so the part of copy_items() that does hole detection will
decide that there is a hole in the range starting from 68K to 76K - 1,
and therefore insert a file extent item to represent that hole, having
a key offset of 68K. After that we now have a log tree with 2 different
extent items that have overlapping ranges:

 1) The file extent item copied before copy_items() released the path,
    which has a key offset of 72K and a length of 4K, representing the
    file range 72K to 76K - 1.

 2) And a file extent item representing a hole that has a key offset of
    68K and a length of 8K, representing the range 68K to 76K - 1. This
    item was inserted after releasing the path, and overlaps with the
    extent item inserted before.

The overlapping extent items can cause all sorts of unpredictable and
incorrect behaviour, either when replayed or if a fast (non full) fsync
happens later, which can trigger a BUG_ON() when calling
btrfs_set_item_key_safe() through __btrfs_drop_extents(), producing a
trace like the following:

  [61666.783269] ------------[ cut here ]------------
  [61666.783943] kernel BUG at fs/btrfs/ctree.c:3182!
  [61666.784644] invalid opcode: 0000 [#1] PREEMPT SMP
  (...)
  [61666.786253] task: ffff880117b88c40 task.stack: ffffc90008168000
  [61666.786253] RIP: 0010:btrfs_set_item_key_safe+0x7c/0xd2 [btrfs]
  [61666.786253] RSP: 0018:ffffc9000816b958 EFLAGS: 00010246
  [61666.786253] RAX: 0000000000000000 RBX: 000000000000000f RCX: 0000000000030000
  [61666.786253] RDX: 0000000000000000 RSI: ffffc9000816ba4f RDI: ffffc9000816b937
  [61666.786253] RBP: ffffc9000816b998 R08: ffff88011dae2428 R09: 0000000000001000
  [61666.786253] R10: 0000160000000000 R11: 6db6db6db6db6db7 R12: ffff88011dae2418
  [61666.786253] R13: ffffc9000816ba4f R14: ffff8801e10c4118 R15: ffff8801e715c000
  [61666.786253] FS:  00007f6060a18700(0000) GS:ffff88023f5c0000(0000) knlGS:0000000000000000
  [61666.786253] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  [61666.786253] CR2: 00007f6060a28000 CR3: 0000000213e69000 CR4: 00000000000006e0
  [61666.786253] Call Trace:
  [61666.786253]  __btrfs_drop_extents+0x5e3/0xaad [btrfs]
  [61666.786253]  ? time_hardirqs_on+0x9/0x14
  [61666.786253]  btrfs_log_changed_extents+0x294/0x4e0 [btrfs]
  [61666.786253]  ? release_extent_buffer+0x38/0xb4 [btrfs]
  [61666.786253]  btrfs_log_inode+0xb6e/0xcdc [btrfs]
  [61666.786253]  ? lock_acquire+0x131/0x1c5
  [61666.786253]  ? btrfs_log_inode_parent+0xee/0x659 [btrfs]
  [61666.786253]  ? arch_local_irq_save+0x9/0xc
  [61666.786253]  ? btrfs_log_inode_parent+0x1f5/0x659 [btrfs]
  [61666.786253]  btrfs_log_inode_parent+0x223/0x659 [btrfs]
  [61666.786253]  ? arch_local_irq_save+0x9/0xc
  [61666.786253]  ? lockref_get_not_zero+0x2c/0x34
  [61666.786253]  ? rcu_read_unlock+0x3e/0x5d
  [61666.786253]  btrfs_log_dentry_safe+0x60/0x7b [btrfs]
  [61666.786253]  btrfs_sync_file+0x317/0x42c [btrfs]
  [61666.786253]  vfs_fsync_range+0x8c/0x9e
  [61666.786253]  SyS_msync+0x13c/0x1c9
  [61666.786253]  entry_SYSCALL_64_fastpath+0x18/0xad

A sample of a corrupt log tree leaf with overlapping extents I got from
running btrfs/072:

      item 14 key (295 108 200704) itemoff 2599 itemsize 53
              extent data disk bytenr 0 nr 0
              extent data offset 0 nr 458752 ram 458752
      item 15 key (295 108 659456) itemoff 2546 itemsize 53
              extent data disk bytenr 4343541760 nr 770048
              extent data offset 606208 nr 163840 ram 770048
      item 16 key (295 108 663552) itemoff 2493 itemsize 53
              extent data disk bytenr 4343541760 nr 770048
              extent data offset 610304 nr 155648 ram 770048
      item 17 key (295 108 819200) itemoff 2440 itemsize 53
              extent data disk bytenr 4334788608 nr 4096
              extent data offset 0 nr 4096 ram 4096

The file extent item at offset 659456 (item 15) ends at offset 823296
(659456 + 163840) while the next file extent item (item 16) starts at
offset 663552.

Another different problem that the race can trigger is a failure in the
assertions at tree-log.c:copy_items(), which expect that the first file
extent item key we found before releasing the path exists after we have
released path and that the last key we found before releasing the path
also exists after releasing the path:

  $ cat -n fs/btrfs/tree-log.c
  4080          if (need_find_last_extent) {
  4081                  /* btrfs_prev_leaf could return 1 without releasing the path */
  4082                  btrfs_release_path(src_path);
  4083                  ret = btrfs_search_slot(NULL, inode->root, &first_key,
  4084                                  src_path, 0, 0);
  4085                  if (ret < 0)
  4086                          return ret;
  4087                  ASSERT(ret == 0);
  (...)
  4103                  if (i >= btrfs_header_nritems(src_path->nodes[0])) {
  4104                          ret = btrfs_next_leaf(inode->root, src_path);
  4105                          if (ret < 0)
  4106                                  return ret;
  4107                          ASSERT(ret == 0);
  4108                          src = src_path->nodes[0];
  4109                          i = 0;
  4110                          need_find_last_extent = true;
  4111                  }
  (...)

The second assertion implicitly expects that the last key before the path
release still exists, because the surrounding while loop only stops after
we have found that key. When this assertion fails it produces a stack like
this:

  [139590.037075] assertion failed: ret == 0, file: fs/btrfs/tree-log.c, line: 4107
  [139590.037406] ------------[ cut here ]------------
  [139590.037707] kernel BUG at fs/btrfs/ctree.h:3546!
  [139590.038034] invalid opcode: 0000 [#1] SMP DEBUG_PAGEALLOC PTI
  [139590.038340] CPU: 1 PID: 31841 Comm: fsstress Tainted: G        W         5.0.0-btrfs-next-46 #1
  (...)
  [139590.039354] RIP: 0010:assfail.constprop.24+0x18/0x1a [btrfs]
  (...)
  [139590.040397] RSP: 0018:ffffa27f48f2b9b0 EFLAGS: 00010282
  [139590.040730] RAX: 0000000000000041 RBX: ffff897c635d92c8 RCX: 0000000000000000
  [139590.041105] RDX: 0000000000000000 RSI: ffff897d36a96868 RDI: ffff897d36a96868
  [139590.041470] RBP: ffff897d1b9a0708 R08: 0000000000000000 R09: 0000000000000000
  [139590.041815] R10: 0000000000000008 R11: 0000000000000000 R12: 0000000000000013
  [139590.042159] R13: 0000000000000227 R14: ffff897cffcbba88 R15: 0000000000000001
  [139590.042501] FS:  00007f2efc8dee80(0000) GS:ffff897d36a80000(0000) knlGS:0000000000000000
  [139590.042847] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  [139590.043199] CR2: 00007f8c064935e0 CR3: 0000000232252002 CR4: 00000000003606e0
  [139590.043547] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
  [139590.043899] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
  [139590.044250] Call Trace:
  [139590.044631]  copy_items+0xa3f/0x1000 [btrfs]
  [139590.045009]  ? generic_bin_search.constprop.32+0x61/0x200 [btrfs]
  [139590.045396]  btrfs_log_inode+0x7b3/0xd70 [btrfs]
  [139590.045773]  btrfs_log_inode_parent+0x2b3/0xce0 [btrfs]
  [139590.046143]  ? do_raw_spin_unlock+0x49/0xc0
  [139590.046510]  btrfs_log_dentry_safe+0x4a/0x70 [btrfs]
  [139590.046872]  btrfs_sync_file+0x3b6/0x440 [btrfs]
  [139590.047243]  btrfs_file_write_iter+0x45b/0x5c0 [btrfs]
  [139590.047592]  __vfs_write+0x129/0x1c0
  [139590.047932]  vfs_write+0xc2/0x1b0
  [139590.048270]  ksys_write+0x55/0xc0
  [139590.048608]  do_syscall_64+0x60/0x1b0
  [139590.048946]  entry_SYSCALL_64_after_hwframe+0x49/0xbe
  [139590.049287] RIP: 0033:0x7f2efc4be190
  (...)
  [139590.050342] RSP: 002b:00007ffe743243a8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
  [139590.050701] RAX: ffffffffffffffda RBX: 0000000000008d58 RCX: 00007f2efc4be190
  [139590.051067] RDX: 0000000000008d58 RSI: 00005567eca0f370 RDI: 0000000000000003
  [139590.051459] RBP: 0000000000000024 R08: 0000000000000003 R09: 0000000000008d60
  [139590.051863] R10: 0000000000000078 R11: 0000000000000246 R12: 0000000000000003
  [139590.052252] R13: 00000000003d3507 R14: 00005567eca0f370 R15: 0000000000000000
  (...)
  [139590.055128] ---[ end trace 193f35d0215cdeeb ]---

So fix this race between a full ranged fsync and writeback of adjacent
ranges by flushing all delalloc and waiting for all ordered extents to
complete before logging the inode. This is the simplest way to solve the
problem because currently the full fsync path does not deal with ranges
at all (it assumes a full range from 0 to LLONG_MAX) and it always needs
to look at adjacent ranges for hole detection. For use cases of ranged
fsyncs this can make a few fsyncs slower but on the other hand it can
make some following fsyncs to other ranges do less work or no need to do
anything at all. A full fsync is rare anyway and happens only once after
loading/creating an inode and once after less common operations such as a
shrinking truncate.

This is an issue that exists for a long time, and was often triggered by
generic/127, because it does mmap'ed writes and msync (which triggers a
ranged fsync). Adding support for the tree checker to detect overlapping
extents (next patch in the series) and trigger a WARN() when such cases
are found, and then calling btrfs_check_leaf_full() at the end of
btrfs_insert_file_extent() made the issue much easier to detect. Running
btrfs/072 with that change to the tree checker and making fsstress open
files always with O_SYNC made it much easier to trigger the issue (as
triggering it with generic/127 is very rare).

CC: stable@vger.kernel.org # 3.16+
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
5 years agoBtrfs: avoid fallback to transaction commit during fsync of files with holes
Filipe Manana [Mon, 6 May 2019 15:43:51 +0000 (16:43 +0100)]
Btrfs: avoid fallback to transaction commit during fsync of files with holes

commit ebb929060aeb162417b4c1307e63daee47b208d9 upstream.

When we are doing a full fsync (bit BTRFS_INODE_NEEDS_FULL_SYNC set) of a
file that has holes and has file extent items spanning two or more leafs,
we can end up falling to back to a full transaction commit due to a logic
bug that leads to failure to insert a duplicate file extent item that is
meant to represent a hole between the last file extent item of a leaf and
the first file extent item in the next leaf. The failure (EEXIST error)
leads to a transaction commit (as most errors when logging an inode do).

For example, we have the two following leafs:

Leaf N:

  -----------------------------------------------
  | ..., ..., ..., (257, FILE_EXTENT_ITEM, 64K) |
  -----------------------------------------------
  The file extent item at the end of leaf N has a length of 4Kb,
  representing the file range from 64K to 68K - 1.

Leaf N + 1:

  -----------------------------------------------
  | (257, FILE_EXTENT_ITEM, 72K), ..., ..., ... |
  -----------------------------------------------
  The file extent item at the first slot of leaf N + 1 has a length of
  4Kb too, representing the file range from 72K to 76K - 1.

During the full fsync path, when we are at tree-log.c:copy_items() with
leaf N as a parameter, after processing the last file extent item, that
represents the extent at offset 64K, we take a look at the first file
extent item at the next leaf (leaf N + 1), and notice there's a 4K hole
between the two extents, and therefore we insert a file extent item
representing that hole, starting at file offset 68K and ending at offset
72K - 1. However we don't update the value of *last_extent, which is used
to represent the end offset (plus 1, non-inclusive end) of the last file
extent item inserted in the log, so it stays with a value of 68K and not
with a value of 72K.

Then, when copy_items() is called for leaf N + 1, because the value of
*last_extent is smaller then the offset of the first extent item in the
leaf (68K < 72K), we look at the last file extent item in the previous
leaf (leaf N) and see it there's a 4K gap between it and our first file
extent item (again, 68K < 72K), so we decide to insert a file extent item
representing the hole, starting at file offset 68K and ending at offset
72K - 1, this insertion will fail with -EEXIST being returned from
btrfs_insert_file_extent() because we already inserted a file extent item
representing a hole for this offset (68K) in the previous call to
copy_items(), when processing leaf N.

The -EEXIST error gets propagated to the fsync callback, btrfs_sync_file(),
which falls back to a full transaction commit.

Fix this by adjusting *last_extent after inserting a hole when we had to
look at the next leaf.

Fixes: 4ee3fad34a9c ("Btrfs: fix fsync after hole punching when using no-holes feature")
Cc: stable@vger.kernel.org # 4.14+
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
5 years agoBtrfs: do not abort transaction at btrfs_update_root() after failure to COW path
Filipe Manana [Mon, 29 Apr 2019 12:08:14 +0000 (13:08 +0100)]
Btrfs: do not abort transaction at btrfs_update_root() after failure to COW path

commit 72bd2323ec87722c115a5906bc6a1b31d11e8f54 upstream.

Currently when we fail to COW a path at btrfs_update_root() we end up
always aborting the transaction. However all the current callers of
btrfs_update_root() are able to deal with errors returned from it, many do
end up aborting the transaction themselves (directly or not, such as the
transaction commit path), other BUG_ON() or just gracefully cancel whatever
they were doing.

When syncing the fsync log, we call btrfs_update_root() through
tree-log.c:update_log_root(), and if it returns an -ENOSPC error, the log
sync code does not abort the transaction, instead it gracefully handles
the error and returns -EAGAIN to the fsync handler, so that it falls back
to a transaction commit. Any other error different from -ENOSPC, makes the
log sync code abort the transaction.

So remove the transaction abort from btrfs_update_log() when we fail to
COW a path to update the root item, so that if an -ENOSPC failure happens
we avoid aborting the current transaction and have a chance of the fsync
succeeding after falling back to a transaction commit.

Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=203413
Fixes: 79787eaab46121 ("btrfs: replace many BUG_ONs with proper error handling")
Cc: stable@vger.kernel.org # 4.4+
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
5 years agobtrfs: don't double unlock on error in btrfs_punch_hole
Josef Bacik [Fri, 3 May 2019 15:10:06 +0000 (11:10 -0400)]
btrfs: don't double unlock on error in btrfs_punch_hole

commit 8fca955057b9c58467d1b231e43f19c4cf26ae8c upstream.

If we have an error writing out a delalloc range in
btrfs_punch_hole_lock_range we'll unlock the inode and then goto
out_only_mutex, where we will again unlock the inode.  This is bad,
don't do this.

Fixes: f27451f22996 ("Btrfs: add support for fallocate's zero range operation")
CC: stable@vger.kernel.org # 4.19+
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
5 years agogfs2: Fix sign extension bug in gfs2_update_stats
Andreas Gruenbacher [Fri, 17 May 2019 18:18:43 +0000 (19:18 +0100)]
gfs2: Fix sign extension bug in gfs2_update_stats

commit 5a5ec83d6ac974b12085cd99b196795f14079037 upstream.

Commit 4d207133e9c3 changed the types of the statistic values in struct
gfs2_lkstats from s64 to u64.  Because of that, what should be a signed
value in gfs2_update_stats turned into an unsigned value.  When shifted
right, we end up with a large positive value instead of a small negative
value, which results in an incorrect variance estimate.

Fixes: 4d207133e9c3 ("gfs2: Make statistics unsigned, suitable for use with do_div()")
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Cc: stable@vger.kernel.org # v4.4+
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
5 years agoarm64/iommu: handle non-remapped addresses in ->mmap and ->get_sgtable
Christoph Hellwig [Tue, 30 Apr 2019 10:51:50 +0000 (06:51 -0400)]
arm64/iommu: handle non-remapped addresses in ->mmap and ->get_sgtable

commit a98d9ae937d256ed679a935fc82d9deaa710d98e upstream.

DMA allocations that can't sleep may return non-remapped addresses, but
we do not properly handle them in the mmap and get_sgtable methods.
Resolve non-vmalloc addresses using virt_to_page to handle this corner
case.

Cc: <stable@vger.kernel.org>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
5 years agoarm64/kernel: kaslr: reduce module randomization range to 2 GB
Ard Biesheuvel [Thu, 23 May 2019 09:17:37 +0000 (10:17 +0100)]
arm64/kernel: kaslr: reduce module randomization range to 2 GB

commit b2eed9b58811283d00fa861944cb75797d4e52a7 upstream.

The following commit

  7290d5809571 ("module: use relative references for __ksymtab entries")

updated the ksymtab handling of some KASLR capable architectures
so that ksymtab entries are emitted as pairs of 32-bit relative
references. This reduces the size of the entries, but more
importantly, it gets rid of statically assigned absolute
addresses, which require fixing up at boot time if the kernel
is self relocating (which takes a 24 byte RELA entry for each
member of the ksymtab struct).

Since ksymtab entries are always part of the same module as the
symbol they export, it was assumed at the time that a 32-bit
relative reference is always sufficient to capture the offset
between a ksymtab entry and its target symbol.

Unfortunately, this is not always true: in the case of per-CPU
variables, a per-CPU variable's base address (which usually differs
from the actual address of any of its per-CPU copies) is allocated
in the vicinity of the ..data.percpu section in the core kernel
(i.e., in the per-CPU reserved region which follows the section
containing the core kernel's statically allocated per-CPU variables).

Since we randomize the module space over a 4 GB window covering
the core kernel (based on the -/+ 4 GB range of an ADRP/ADD pair),
we may end up putting the core kernel out of the -/+ 2 GB range of
32-bit relative references of module ksymtab entries that refer to
per-CPU variables.

So reduce the module randomization range a bit further. We lose
1 bit of randomization this way, but this is something we can
tolerate.

Cc: <stable@vger.kernel.org> # v4.19+
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
5 years agolibnvdimm/pmem: Bypass CONFIG_HARDENED_USERCOPY overhead
Dan Williams [Fri, 17 May 2019 00:05:21 +0000 (17:05 -0700)]
libnvdimm/pmem: Bypass CONFIG_HARDENED_USERCOPY overhead

commit 52f476a323f9efc959be1c890d0cdcf12e1582e0 upstream.

Jeff discovered that performance improves from ~375K iops to ~519K iops
on a simple psync-write fio workload when moving the location of 'struct
page' from the default PMEM location to DRAM. This result is surprising
because the expectation is that 'struct page' for dax is only needed for
third party references to dax mappings. For example, a dax-mapped buffer
passed to another system call for direct-I/O requires 'struct page' for
sending the request down the driver stack and pinning the page. There is
no usage of 'struct page' for first party access to a file via
read(2)/write(2) and friends.

However, this "no page needed" expectation is violated by
CONFIG_HARDENED_USERCOPY and the check_copy_size() performed in
copy_from_iter_full_nocache() and copy_to_iter_mcsafe(). The
check_heap_object() helper routine assumes the buffer is backed by a
slab allocator (DRAM) page and applies some checks.  Those checks are
invalid, dax pages do not originate from the slab, and redundant,
dax_iomap_actor() has already validated that the I/O is within bounds.
Specifically that routine validates that the logical file offset is
within bounds of the file, then it does a sector-to-pfn translation
which validates that the physical mapping is within bounds of the block
device.

Bypass additional hardened usercopy overhead and call the 'no check'
versions of the copy_{to,from}_iter operations directly.

Fixes: 0aed55af8834 ("x86, uaccess: introduce copy_from_iter_flushcache...")
Cc: <stable@vger.kernel.org>
Cc: Jeff Moyer <jmoyer@redhat.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Matthew Wilcox <willy@infradead.org>
Reported-and-tested-by: Jeff Smits <jeff.smits@intel.com>
Acked-by: Kees Cook <keescook@chromium.org>
Acked-by: Jan Kara <jack@suse.cz>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
5 years agokvm: svm/avic: fix off-by-one in checking host APIC ID
Suthikulpanit, Suravee [Tue, 14 May 2019 15:49:52 +0000 (15:49 +0000)]
kvm: svm/avic: fix off-by-one in checking host APIC ID

commit c9bcd3e3335d0a29d89fabd2c385e1b989e6f1b0 upstream.

Current logic does not allow VCPU to be loaded onto CPU with
APIC ID 255. This should be allowed since the host physical APIC ID
field in the AVIC Physical APIC table entry is an 8-bit value,
and APIC ID 255 is valid in system with x2APIC enabled.
Instead, do not allow VCPU load if the host APIC ID cannot be
represented by an 8-bit value.

Also, use the more appropriate AVIC_PHYSICAL_ID_ENTRY_HOST_PHYSICAL_ID_MASK
instead of AVIC_MAX_PHYSICAL_ID_COUNT.

Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
5 years agommc: sdhci-iproc: Set NO_HISPD bit to fix HS50 data hold time problem
Trac Hoang [Thu, 9 May 2019 17:24:27 +0000 (10:24 -0700)]
mmc: sdhci-iproc: Set NO_HISPD bit to fix HS50 data hold time problem

commit ec0970e0a1b2c807c908d459641a9f9a1be3e130 upstream.

The iproc host eMMC/SD controller hold time does not meet the
specification in the HS50 mode.  This problem can be mitigated
by disabling the HISPD bit; thus forcing the controller output
data to be driven on the falling clock edges rather than the
rising clock edges.

Stable tag (v4.12+) chosen to assist stable kernel maintainers so that
the change does not produce merge conflicts backporting to older kernel
versions. In reality, the timing bug existed since the driver was first
introduced but there is no need for this driver to be supported in kernel
versions that old.

Cc: stable@vger.kernel.org # v4.12+
Signed-off-by: Trac Hoang <trac.hoang@broadcom.com>
Signed-off-by: Scott Branden <scott.branden@broadcom.com>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
5 years agommc: sdhci-iproc: cygnus: Set NO_HISPD bit to fix HS50 data hold time problem
Trac Hoang [Thu, 9 May 2019 17:24:26 +0000 (10:24 -0700)]
mmc: sdhci-iproc: cygnus: Set NO_HISPD bit to fix HS50 data hold time problem

commit b7dfa695afc40d5396ed84b9f25aa3754de23e39 upstream.

The iproc host eMMC/SD controller hold time does not meet the
specification in the HS50 mode. This problem can be mitigated
by disabling the HISPD bit; thus forcing the controller output
data to be driven on the falling clock edges rather than the
rising clock edges.

This change applies only to the Cygnus platform.

Stable tag (v4.12+) chosen to assist stable kernel maintainers so that
the change does not produce merge conflicts backporting to older kernel
versions. In reality, the timing bug existed since the driver was first
introduced but there is no need for this driver to be supported in kernel
versions that old.

Cc: stable@vger.kernel.org # v4.12+
Signed-off-by: Trac Hoang <trac.hoang@broadcom.com>
Signed-off-by: Scott Branden <scott.branden@broadcom.com>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
5 years agocrypto: vmx - CTR: always increment IV as quadword
Daniel Axtens [Wed, 15 May 2019 10:24:50 +0000 (20:24 +1000)]
crypto: vmx - CTR: always increment IV as quadword

commit 009b30ac7444c17fae34c4f435ebce8e8e2b3250 upstream.

The kernel self-tests picked up an issue with CTR mode:
alg: skcipher: p8_aes_ctr encryption test failed (wrong result) on test vector 3, cfg="uneven misaligned splits, may sleep"

Test vector 3 has an IV of FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFD, so
after 3 increments it should wrap around to 0.

In the aesp8-ppc code from OpenSSL, there are two paths that
increment IVs: the bulk (8 at a time) path, and the individual
path which is used when there are fewer than 8 AES blocks to
process.

In the bulk path, the IV is incremented with vadduqm: "Vector
Add Unsigned Quadword Modulo", which does 128-bit addition.

In the individual path, however, the IV is incremented with
vadduwm: "Vector Add Unsigned Word Modulo", which instead
does 4 32-bit additions. Thus the IV would instead become
FFFFFFFFFFFFFFFFFFFFFFFF00000000, throwing off the result.

Use vadduqm.

This was probably a typo originally, what with q and w being
adjacent. It is a pretty narrow edge case: I am really
impressed by the quality of the kernel self-tests!

Fixes: 5c380d623ed3 ("crypto: vmx - Add support for VMS instructions by ASM")
Cc: stable@vger.kernel.org
Signed-off-by: Daniel Axtens <dja@axtens.net>
Acked-by: Nayna Jain <nayna@linux.ibm.com>
Tested-by: Nayna Jain <nayna@linux.ibm.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
5 years agoRevert "scsi: sd: Keep disk read-only when re-reading partition"
Martin K. Petersen [Mon, 20 May 2019 14:57:18 +0000 (10:57 -0400)]
Revert "scsi: sd: Keep disk read-only when re-reading partition"

commit 8acf608e602f6ec38b7cc37b04c80f1ce9a1a6cc upstream.

This reverts commit 20bd1d026aacc5399464f8328f305985c493cde3.

This patch introduced regressions for devices that come online in
read-only state and subsequently switch to read-write.

Given how the partition code is currently implemented it is not
possible to persist the read-only flag across a device revalidate
call. This may need to get addressed in the future since it is common
for user applications to proactively call BLKRRPART.

Reverting this commit will re-introduce a regression where a
device-initiated revalidate event will cause the admin state to be
forgotten. A separate patch will address this issue.

Fixes: 20bd1d026aac ("scsi: sd: Keep disk read-only when re-reading partition")
Cc: <stable@vger.kernel.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
5 years agosbitmap: fix improper use of smp_mb__before_atomic()
Andrea Parri [Mon, 20 May 2019 17:23:57 +0000 (19:23 +0200)]
sbitmap: fix improper use of smp_mb__before_atomic()

commit a0934fd2b1208458e55fc4b48f55889809fce666 upstream.

This barrier only applies to the read-modify-write operations; in
particular, it does not apply to the atomic_set() primitive.

Replace the barrier with an smp_mb().

Fixes: 6c0ca7ae292ad ("sbitmap: fix wakeup hang after sbq resize")
Cc: stable@vger.kernel.org
Reported-by: "Paul E. McKenney" <paulmck@linux.ibm.com>
Reported-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Andrea Parri <andrea.parri@amarulasolutions.com>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Omar Sandoval <osandov@fb.com>
Cc: Ming Lei <ming.lei@redhat.com>
Cc: linux-block@vger.kernel.org
Cc: "Paul E. McKenney" <paulmck@linux.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
5 years agobio: fix improper use of smp_mb__before_atomic()
Andrea Parri [Mon, 20 May 2019 17:23:56 +0000 (19:23 +0200)]
bio: fix improper use of smp_mb__before_atomic()

commit f381c6a4bd0ae0fde2d6340f1b9bb0f58d915de6 upstream.

This barrier only applies to the read-modify-write operations; in
particular, it does not apply to the atomic_set() primitive.

Replace the barrier with an smp_mb().

Fixes: dac56212e8127 ("bio: skip atomic inc/dec of ->bi_cnt for most use cases")
Cc: stable@vger.kernel.org
Reported-by: "Paul E. McKenney" <paulmck@linux.ibm.com>
Reported-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Andrea Parri <andrea.parri@amarulasolutions.com>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Ming Lei <ming.lei@redhat.com>
Cc: linux-block@vger.kernel.org
Cc: "Paul E. McKenney" <paulmck@linux.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
5 years agoKVM: x86: fix return value for reserved EFER
Paolo Bonzini [Fri, 24 May 2019 19:52:46 +0000 (21:52 +0200)]
KVM: x86: fix return value for reserved EFER

commit 66f61c92889ff3ca365161fb29dd36d6354682ba upstream.

Commit 11988499e62b ("KVM: x86: Skip EFER vs. guest CPUID checks for
host-initiated writes", 2019-04-02) introduced a "return false" in a
function returning int, and anyway set_efer has a "nonzero on error"
conventon so it should be returning 1.

Reported-by: Pavel Machek <pavel@denx.de>
Fixes: 11988499e62b ("KVM: x86: Skip EFER vs. guest CPUID checks for host-initiated writes")
Cc: Sean Christopherson <sean.j.christopherson@intel.com>
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
5 years agof2fs: Fix use of number of devices
Damien Le Moal [Sat, 16 Mar 2019 00:13:06 +0000 (09:13 +0900)]
f2fs: Fix use of number of devices

commit 0916878da355650d7e77104a7ac0fa1784eca852 upstream.

For a single device mount using a zoned block device, the zone
information for the device is stored in the sbi->devs single entry
array and sbi->s_ndevs is set to 1. This differs from a single device
mount using a regular block device which does not allocate sbi->devs
and sets sbi->s_ndevs to 0.

However, sbi->s_devs == 0 condition is used throughout the code to
differentiate a single device mount from a multi-device mount where
sbi->s_ndevs is always larger than 1. This results in problems with
single zoned block device volumes as these are treated as multi-device
mounts but do not have the start_blk and end_blk information set. One
of the problem observed is skipping of zone discard issuing resulting in
write commands being issued to full zones or unaligned to a zone write
pointer.

Fix this problem by simply treating the cases sbi->s_ndevs == 0 (single
regular block device mount) and sbi->s_ndevs == 1 (single zoned block
device mount) in the same manner. This is done by introducing the
helper function f2fs_is_multi_device() and using this helper in place
of direct tests of sbi->s_ndevs value, improving code readability.

Fixes: 7bb3a371d199 ("f2fs: Fix zoned block device support")
Cc: <stable@vger.kernel.org>
Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
5 years agoext4: wait for outstanding dio during truncate in nojournal mode
Jan Kara [Fri, 24 May 2019 03:07:08 +0000 (23:07 -0400)]
ext4: wait for outstanding dio during truncate in nojournal mode

commit 82a25b027ca48d7ef197295846b352345853dfa8 upstream.

We didn't wait for outstanding direct IO during truncate in nojournal
mode (as we skip orphan handling in that case). This can lead to fs
corruption or stale data exposure if truncate ends up freeing blocks
and these get reallocated before direct IO finishes. Fix the condition
determining whether the wait is necessary.

CC: stable@vger.kernel.org
Fixes: 1c9114f9c0f1 ("ext4: serialize unlocked dio reads with truncate")
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
5 years agoext4: do not delete unlinked inode from orphan list on failed truncate
Jan Kara [Fri, 24 May 2019 03:35:28 +0000 (23:35 -0400)]
ext4: do not delete unlinked inode from orphan list on failed truncate

commit ee0ed02ca93ef1ecf8963ad96638795d55af2c14 upstream.

It is possible that unlinked inode enters ext4_setattr() (e.g. if
somebody calls ftruncate(2) on unlinked but still open file). In such
case we should not delete the inode from the orphan list if truncate
fails. Note that this is mostly a theoretical concern as filesystem is
corrupted if we reach this path anyway but let's be consistent in our
orphan handling.

Reviewed-by: Ira Weiny <ira.weiny@intel.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
5 years agox86: Hide the int3_emulate_call/jmp functions from UML
Steven Rostedt (VMware) [Sat, 11 May 2019 12:32:40 +0000 (08:32 -0400)]
x86: Hide the int3_emulate_call/jmp functions from UML

commit 693713cbdb3a4bda5a8a678c31f06560bbb14657 upstream.

User Mode Linux does not have access to the ip or sp fields of the pt_regs,
and accessing them causes UML to fail to build. Hide the int3_emulate_jmp()
and int3_emulate_call() instructions from UML, as it doesn't need them
anyway.

Reported-by: kbuild test robot <lkp@intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
5 years agoLinux 4.19.46 v4.19.46
Greg Kroah-Hartman [Sat, 25 May 2019 16:23:48 +0000 (18:23 +0200)]
Linux 4.19.46

5 years agofbdev: sm712fb: fix memory frequency by avoiding a switch/case fallthrough
Yifeng Li [Tue, 2 Apr 2019 15:14:10 +0000 (17:14 +0200)]
fbdev: sm712fb: fix memory frequency by avoiding a switch/case fallthrough

commit 9dc20113988b9a75ea6b3abd68dc45e2d73ccdab upstream.

A fallthrough in switch/case was introduced in f627caf55b8e ("fbdev:
sm712fb: fix crashes and garbled display during DPMS modesetting"),
due to my copy-paste error, which would cause the memory clock frequency
for SM720 to be programmed to SM712.

Since it only reprograms the clock to a different frequency, it's only
a benign issue without visible side-effect, so it also evaded Sudip
Mukherjee's code review and regression tests. scripts/checkpatch.pl
also failed to discover the issue, possibly due to nested switch
statements.

This issue was found by Stephen Rothwell by building linux-next with
-Wimplicit-fallthrough.

Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Fixes: f627caf55b8e ("fbdev: sm712fb: fix crashes and garbled display during DPMS modesetting")
Signed-off-by: Yifeng Li <tomli@tomli.me>
Cc: Sudip Mukherjee <sudipm.mukherjee@gmail.com>
Cc: "Gustavo A. R. Silva" <gustavo@embeddedor.com>
Cc: Kees Cook <keescook@chromium.org>
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
5 years agobpf, lru: avoid messing with eviction heuristics upon syscall lookup
Daniel Borkmann [Mon, 13 May 2019 23:18:56 +0000 (01:18 +0200)]
bpf, lru: avoid messing with eviction heuristics upon syscall lookup

commit 50b045a8c0ccf44f76640ac3eea8d80ca53979a3 upstream.

One of the biggest issues we face right now with picking LRU map over
regular hash table is that a map walk out of user space, for example,
to just dump the existing entries or to remove certain ones, will
completely mess up LRU eviction heuristics and wrong entries such
as just created ones will get evicted instead. The reason for this
is that we mark an entry as "in use" via bpf_lru_node_set_ref() from
system call lookup side as well. Thus upon walk, all entries are
being marked, so information of actual least recently used ones
are "lost".

In case of Cilium where it can be used (besides others) as a BPF
based connection tracker, this current behavior causes disruption
upon control plane changes that need to walk the map from user space
to evict certain entries. Discussion result from bpfconf [0] was that
we should simply just remove marking from system call side as no
good use case could be found where it's actually needed there.
Therefore this patch removes marking for regular LRU and per-CPU
flavor. If there ever should be a need in future, the behavior could
be selected via map creation flag, but due to mentioned reason we
avoid this here.

  [0] http://vger.kernel.org/bpfconf.html

Fixes: 29ba732acbee ("bpf: Add BPF_MAP_TYPE_LRU_HASH")
Fixes: 8f8449384ec3 ("bpf: Add BPF_MAP_TYPE_LRU_PERCPU_HASH")
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
5 years agobpf: add map_lookup_elem_sys_only for lookups from syscall side
Daniel Borkmann [Mon, 13 May 2019 23:18:55 +0000 (01:18 +0200)]
bpf: add map_lookup_elem_sys_only for lookups from syscall side

commit c6110222c6f49ea68169f353565eb865488a8619 upstream.

Add a callback map_lookup_elem_sys_only() that map implementations
could use over map_lookup_elem() from system call side in case the
map implementation needs to handle the latter differently than from
the BPF data path. If map_lookup_elem_sys_only() is set, this will
be preferred pick for map lookups out of user space. This hook is
used in a follow-up fix for LRU map, but once development window
opens, we can convert other map types from map_lookup_elem() (here,
the one called upon BPF_MAP_LOOKUP_ELEM cmd is meant) over to use
the callback to simplify and clean up the latter.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
5 years agobpf: relax inode permission check for retrieving bpf program
Chenbo Feng [Wed, 15 May 2019 02:42:57 +0000 (19:42 -0700)]
bpf: relax inode permission check for retrieving bpf program

commit e547ff3f803e779a3898f1f48447b29f43c54085 upstream.

For iptable module to load a bpf program from a pinned location, it
only retrieve a loaded program and cannot change the program content so
requiring a write permission for it might not be necessary.
Also when adding or removing an unrelated iptable rule, it might need to
flush and reload the xt_bpf related rules as well and triggers the inode
permission check. It might be better to remove the write premission
check for the inode so we won't need to grant write access to all the
processes that flush and restore iptables rules.

Signed-off-by: Chenbo Feng <fengc@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
5 years agoRevert "selftests/bpf: skip verifier tests for unsupported program types"
Greg Kroah-Hartman [Thu, 23 May 2019 17:48:54 +0000 (19:48 +0200)]
Revert "selftests/bpf: skip verifier tests for unsupported program types"

This reverts commit 118d38a3577f7728278f6afda8436af05a6bec7f which is
commit 8184d44c9a577a2f1842ed6cc844bfd4a9981d8e upstream.

Tommi reports that this patch breaks the build, it's not really needed
so let's revert it.

Reported-by: Tommi Rantala <tommi.t.rantala@nokia.com>
Cc: Stanislav Fomichev <sdf@google.com>
Cc: Sasha Levin <sashal@kernel.org>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
5 years agodriver core: Postpone DMA tear-down until after devres release for probe failure
John Garry [Thu, 28 Mar 2019 10:08:05 +0000 (18:08 +0800)]
driver core: Postpone DMA tear-down until after devres release for probe failure

commit 0b777eee88d712256ba8232a9429edb17c4f9ceb upstream.

In commit 376991db4b64 ("driver core: Postpone DMA tear-down until after
devres release"), we changed the ordering of tearing down the device DMA
ops and releasing all the device's resources; this was because the DMA ops
should be maintained until we release the device's managed DMA memories.

However, we have seen another crash on an arm64 system when a
device driver probe fails:

  hisi_sas_v3_hw 0000:74:02.0: Adding to iommu group 2
  scsi host1: hisi_sas_v3_hw
  BUG: Bad page state in process swapper/0  pfn:313f5
  page:ffff7e0000c4fd40 count:1 mapcount:0
  mapping:0000000000000000 index:0x0
  flags: 0xfffe00000001000(reserved)
  raw: 0fffe00000001000 ffff7e0000c4fd48 ffff7e0000c4fd48
0000000000000000
  raw: 0000000000000000 0000000000000000 00000001ffffffff
0000000000000000
  page dumped because: PAGE_FLAGS_CHECK_AT_FREE flag(s) set
  bad because of flags: 0x1000(reserved)
  Modules linked in:
  CPU: 49 PID: 1 Comm: swapper/0 Not tainted
5.1.0-rc1-43081-g22d97fd-dirty #1433
  Hardware name: Huawei D06/D06, BIOS Hisilicon D06 UEFI
RC0 - V1.12.01 01/29/2019
  Call trace:
  dump_backtrace+0x0/0x118
  show_stack+0x14/0x1c
  dump_stack+0xa4/0xc8
  bad_page+0xe4/0x13c
  free_pages_check_bad+0x4c/0xc0
  __free_pages_ok+0x30c/0x340
  __free_pages+0x30/0x44
  __dma_direct_free_pages+0x30/0x38
  dma_direct_free+0x24/0x38
  dma_free_attrs+0x9c/0xd8
  dmam_release+0x20/0x28
  release_nodes+0x17c/0x220
  devres_release_all+0x34/0x54
  really_probe+0xc4/0x2c8
  driver_probe_device+0x58/0xfc
  device_driver_attach+0x68/0x70
  __driver_attach+0x94/0xdc
  bus_for_each_dev+0x5c/0xb4
  driver_attach+0x20/0x28
  bus_add_driver+0x14c/0x200
  driver_register+0x6c/0x124
  __pci_register_driver+0x48/0x50
  sas_v3_pci_driver_init+0x20/0x28
  do_one_initcall+0x40/0x25c
  kernel_init_freeable+0x2b8/0x3c0
  kernel_init+0x10/0x100
  ret_from_fork+0x10/0x18
  Disabling lock debugging due to kernel taint
  BUG: Bad page state in process swapper/0  pfn:313f6
  page:ffff7e0000c4fd80 count:1 mapcount:0
mapping:0000000000000000 index:0x0
[   89.322983] flags: 0xfffe00000001000(reserved)
  raw: 0fffe00000001000 ffff7e0000c4fd88 ffff7e0000c4fd88
0000000000000000
  raw: 0000000000000000 0000000000000000 00000001ffffffff
0000000000000000

The crash occurs for the same reason.

In this case, on the really_probe() failure path, we are still clearing
the DMA ops prior to releasing the device's managed memories.

This patch fixes this issue by reordering the DMA ops teardown and the
call to devres_release_all() on the failure path.

Reported-by: Xiang Chen <chenxiang66@hisilicon.com>
Tested-by: Xiang Chen <chenxiang66@hisilicon.com>
Signed-off-by: John Garry <john.garry@huawei.com>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
[jpg: backport to 4.19.x and earlier]
Signed-off-by: John Garry <john.garry@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
5 years agomd/raid: raid5 preserve the writeback action after the parity check
Nigel Croxon [Tue, 16 Apr 2019 16:50:09 +0000 (09:50 -0700)]
md/raid: raid5 preserve the writeback action after the parity check

commit b2176a1dfb518d870ee073445d27055fea64dfb8 upstream.

The problem is that any 'uptodate' vs 'disks' check is not precise
in this path. Put a "WARN_ON(!test_bit(R5_UPTODATE, &dev->flags)" on the
device that might try to kick off writes and then skip the action.
Better to prevent the raid driver from taking unexpected action *and* keep
the system alive vs killing the machine with BUG_ON.

Note: fixed warning reported by kbuild test robot <lkp@intel.com>

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Nigel Croxon <ncroxon@redhat.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
5 years agoRevert "Don't jump to compute_result state from check_result state"
Song Liu [Tue, 16 Apr 2019 16:34:21 +0000 (09:34 -0700)]
Revert "Don't jump to compute_result state from check_result state"

commit a25d8c327bb41742dbd59f8c545f59f3b9c39983 upstream.

This reverts commit 4f4fd7c5798bbdd5a03a60f6269cf1177fbd11ef.

Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Nigel Croxon <ncroxon@redhat.com>
Cc: Xiao Ni <xni@redhat.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
5 years agoperf/x86/intel: Fix race in intel_pmu_disable_event()
Jiri Olsa [Sat, 4 May 2019 15:15:56 +0000 (17:15 +0200)]
perf/x86/intel: Fix race in intel_pmu_disable_event()

[ Upstream commit 6f55967ad9d9752813e36de6d5fdbd19741adfc7 ]

New race in x86_pmu_stop() was introduced by replacing the
atomic __test_and_clear_bit() of cpuc->active_mask by separate
test_bit() and __clear_bit() calls in the following commit:

  3966c3feca3f ("x86/perf/amd: Remove need to check "running" bit in NMI handler")

The race causes panic for PEBS events with enabled callchains:

  BUG: unable to handle kernel NULL pointer dereference at 0000000000000000
  ...
  RIP: 0010:perf_prepare_sample+0x8c/0x530
  Call Trace:
   <NMI>
   perf_event_output_forward+0x2a/0x80
   __perf_event_overflow+0x51/0xe0
   handle_pmi_common+0x19e/0x240
   intel_pmu_handle_irq+0xad/0x170
   perf_event_nmi_handler+0x2e/0x50
   nmi_handle+0x69/0x110
   default_do_nmi+0x3e/0x100
   do_nmi+0x11a/0x180
   end_repeat_nmi+0x16/0x1a
  RIP: 0010:native_write_msr+0x6/0x20
  ...
   </NMI>
   intel_pmu_disable_event+0x98/0xf0
   x86_pmu_stop+0x6e/0xb0
   x86_pmu_del+0x46/0x140
   event_sched_out.isra.97+0x7e/0x160
  ...

The event is configured to make samples from PEBS drain code,
but when it's disabled, we'll go through NMI path instead,
where data->callchain will not get allocated and we'll crash:

          x86_pmu_stop
            test_bit(hwc->idx, cpuc->active_mask)
            intel_pmu_disable_event(event)
            {
              ...
              intel_pmu_pebs_disable(event);
              ...

EVENT OVERFLOW ->  <NMI>
                     intel_pmu_handle_irq
                       handle_pmi_common
   TEST PASSES ->        test_bit(bit, cpuc->active_mask))
                           perf_event_overflow
                             perf_prepare_sample
                             {
                               ...
                               if (!(sample_type & __PERF_SAMPLE_CALLCHAIN_EARLY))
                                     data->callchain = perf_callchain(event, regs);

         CRASH ->              size += data->callchain->nr;
                             }
                   </NMI>
              ...
              x86_pmu_disable_event(event)
            }

            __clear_bit(hwc->idx, cpuc->active_mask);

Fixing this by disabling the event itself before setting
off the PEBS bit.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: David Arcari <darcari@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Lendacky Thomas <Thomas.Lendacky@amd.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Fixes: 3966c3feca3f ("x86/perf/amd: Remove need to check "running" bit in NMI handler")
Link: http://lkml.kernel.org/r/20190504151556.31031-1-jolsa@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
5 years agoperf bench numa: Add define for RUSAGE_THREAD if not present
Arnaldo Carvalho de Melo [Thu, 25 Apr 2019 21:36:51 +0000 (18:36 -0300)]
perf bench numa: Add define for RUSAGE_THREAD if not present

[ Upstream commit bf561d3c13423fc54daa19b5d49dc15fafdb7acc ]

While cross building perf to the ARC architecture on a fedora 30 host,
we were failing with:

      CC       /tmp/build/perf/bench/numa.o
  bench/numa.c: In function â€˜worker_thread’:
  bench/numa.c:1261:12: error: â€˜RUSAGE_THREAD’ undeclared (first use in this function); did you mean â€˜SIGEV_THREAD’?
    getrusage(RUSAGE_THREAD, &rusage);
              ^~~~~~~~~~~~~
              SIGEV_THREAD
  bench/numa.c:1261:12: note: each undeclared identifier is reported only once for each function it appears in

[perfbuilder@60d5802468f6 perf]$ /arc_gnu_2019.03-rc1_prebuilt_uclibc_le_archs_linux_install/bin/arc-linux-gcc --version | head -1
arc-linux-gcc (ARCv2 ISA Linux uClibc toolchain 2019.03-rc1) 8.3.1 20190225
[perfbuilder@60d5802468f6 perf]$

Trying to reproduce a report by Vineet, I noticed that, with just
cross-built zlib and numactl libraries, I ended up with the above
failure.

So, since RUSAGE_THREAD is available as a define, check for that and
numactl libraries, I ended up with the above failure.

So, since RUSAGE_THREAD is available as a define in the system headers,
check if it is defined in the 'perf bench numa' sources and define it if
not.

Now it builds and I have to figure out if the problem reported by Vineet
only takes place if we have libelf or some other library available.

Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: linux-snps-arc@lists.infradead.org
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Vineet Gupta <Vineet.Gupta1@synopsys.com>
Link: https://lkml.kernel.org/n/tip-2wb4r1gir9xrevbpq7qp0amk@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
5 years agoufs: fix braino in ufs_get_inode_gid() for solaris UFS flavour
Al Viro [Thu, 2 May 2019 02:46:11 +0000 (22:46 -0400)]
ufs: fix braino in ufs_get_inode_gid() for solaris UFS flavour

[ Upstream commit 4e9036042fedaffcd868d7f7aa948756c48c637d ]

To choose whether to pick the GID from the old (16bit) or new (32bit)
field, we should check if the old gid field is set to 0xffff.  Mainline
checks the old *UID* field instead - cut'n'paste from the corresponding
code in ufs_get_inode_uid().

Fixes: 252e211e90ce
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
5 years agox86/mm/mem_encrypt: Disable all instrumentation for early SME setup
Gary Hook [Mon, 29 Apr 2019 22:22:58 +0000 (22:22 +0000)]
x86/mm/mem_encrypt: Disable all instrumentation for early SME setup

[ Upstream commit b51ce3744f115850166f3d6c292b9c8cb849ad4f ]

Enablement of AMD's Secure Memory Encryption feature is determined very
early after start_kernel() is entered. Part of this procedure involves
scanning the command line for the parameter 'mem_encrypt'.

To determine intended state, the function sme_enable() uses library
functions cmdline_find_option() and strncmp(). Their use occurs early
enough such that it cannot be assumed that any instrumentation subsystem
is initialized.

For example, making calls to a KASAN-instrumented function before KASAN
is set up will result in the use of uninitialized memory and a boot
failure.

When AMD's SME support is enabled, conditionally disable instrumentation
of these dependent functions in lib/string.c and arch/x86/lib/cmdline.c.

 [ bp: Get rid of intermediary nostackp var and cleanup whitespace. ]

Fixes: aca20d546214 ("x86/mm: Add support to make use of Secure Memory Encryption")
Reported-by: Li RongQing <lirongqing@baidu.com>
Signed-off-by: Gary R Hook <gary.hook@amd.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Boris Brezillon <bbrezillon@kernel.org>
Cc: Coly Li <colyli@suse.de>
Cc: "dave.hansen@linux.intel.com" <dave.hansen@linux.intel.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Kent Overstreet <kent.overstreet@gmail.com>
Cc: "luto@kernel.org" <luto@kernel.org>
Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: "mingo@redhat.com" <mingo@redhat.com>
Cc: "peterz@infradead.org" <peterz@infradead.org>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: x86-ml <x86@kernel.org>
Link: https://lkml.kernel.org/r/155657657552.7116.18363762932464011367.stgit@sosrh3.amd.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
5 years agosched/cpufreq: Fix kobject memleak
Tobin C. Harding [Tue, 30 Apr 2019 00:11:44 +0000 (10:11 +1000)]
sched/cpufreq: Fix kobject memleak

[ Upstream commit 9a4f26cc98d81b67ecc23b890c28e2df324e29f3 ]

Currently the error return path from kobject_init_and_add() is not
followed by a call to kobject_put() - which means we are leaking
the kobject.

Fix it by adding a call to kobject_put() in the error path of
kobject_init_and_add().

Signed-off-by: Tobin C. Harding <tobin@kernel.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tobin C. Harding <tobin@kernel.org>
Cc: Vincent Guittot <vincent.guittot@linaro.org>
Cc: Viresh Kumar <viresh.kumar@linaro.org>
Link: http://lkml.kernel.org/r/20190430001144.24890-1-tobin@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
5 years agoiwlwifi: mvm: check for length correctness in iwl_mvm_create_skb()
Luca Coelho [Tue, 16 Apr 2019 09:57:21 +0000 (12:57 +0300)]
iwlwifi: mvm: check for length correctness in iwl_mvm_create_skb()

[ Upstream commit de1887c064b9996ac03120d90d0a909a3f678f98 ]

We don't check for the validity of the lengths in the packet received
from the firmware.  If the MPDU length received in the rx descriptor
is too short to contain the header length and the crypt length
together, we may end up trying to copy a negative number of bytes
(headlen - hdrlen < 0) which will underflow and cause us to try to
copy a huge amount of data.  This causes oopses such as this one:

BUG: unable to handle kernel paging request at ffff896be2970000
PGD 5e201067 P4D 5e201067 PUD 5e205067 PMD 16110d063 PTE 8000000162970161
Oops: 0003 [#1] PREEMPT SMP NOPTI
CPU: 2 PID: 1824 Comm: irq/134-iwlwifi Not tainted 4.19.33-04308-geea41cf4930f #1
Hardware name: [...]
RIP: 0010:memcpy_erms+0x6/0x10
Code: 90 90 90 90 eb 1e 0f 1f 00 48 89 f8 48 89 d1 48 c1 e9 03 83 e2 07 f3 48 a5 89 d1 f3 a4 c3 66 0f 1f 44 00 00 48 89 f8 48 89 d1 <f3> a4 c3
 0f 1f 80 00 00 00 00 48 89 f8 48 83 fa 20 72 7e 40 38 fe
RSP: 0018:ffffa4630196fc60 EFLAGS: 00010287
RAX: ffff896be2924618 RBX: ffff896bc8ecc600 RCX: 00000000fffb4610
RDX: 00000000fffffff8 RSI: ffff896a835e2a38 RDI: ffff896be2970000
RBP: ffffa4630196fd30 R08: ffff896bc8ecc600 R09: ffff896a83597000
R10: ffff896bd6998400 R11: 000000000200407f R12: ffff896a83597050
R13: 00000000fffffff8 R14: 0000000000000010 R15: ffff896a83597038
FS:  0000000000000000(0000) GS:ffff896be8280000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffff896be2970000 CR3: 000000005dc12002 CR4: 00000000003606e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 iwl_mvm_rx_mpdu_mq+0xb51/0x121b [iwlmvm]
 iwl_pcie_rx_handle+0x58c/0xa89 [iwlwifi]
 iwl_pcie_irq_rx_msix_handler+0xd9/0x12a [iwlwifi]
 irq_thread_fn+0x24/0x49
 irq_thread+0xb0/0x122
 kthread+0x138/0x140
 ret_from_fork+0x1f/0x40

Fix that by checking the lengths for correctness and trigger a warning
to show that we have received wrong data.

Signed-off-by: Luca Coelho <luciano.coelho@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
5 years agoqmi_wwan: new Wistron, ZTE and D-Link devices
Bjørn Mork [Wed, 24 Apr 2019 17:12:46 +0000 (19:12 +0200)]
qmi_wwan: new Wistron, ZTE and D-Link devices

[ Upstream commit 88ef66a28391ea7b624bfb7508a5b015c13b28f3 ]

Adding device entries found in vendor modified versions of this
driver.  Function maps for some of the devices follow:

WNC D16Q1, D16Q5, D18Q1 LTE CAT3 module (1435:0918)

MI_00 Qualcomm HS-USB Diagnostics
MI_01 Android Debug interface
MI_02 Qualcomm HS-USB Modem
MI_03 Qualcomm Wireless HS-USB Ethernet Adapter
MI_04 Qualcomm Wireless HS-USB Ethernet Adapter
MI_05 Qualcomm Wireless HS-USB Ethernet Adapter
MI_06 USB Mass Storage Device

 T:  Bus=02 Lev=01 Prnt=01 Port=00 Cnt=01 Dev#=  2 Spd=480 MxCh= 0
 D:  Ver= 2.00 Cls=00(>ifc ) Sub=00 Prot=00 MxPS=64 #Cfgs=  1
 P:  Vendor=1435 ProdID=0918 Rev= 2.32
 S:  Manufacturer=Android
 S:  Product=Android
 S:  SerialNumber=0123456789ABCDEF
 C:* #Ifs= 7 Cfg#= 1 Atr=80 MxPwr=500mA
 I:* If#= 0 Alt= 0 #EPs= 2 Cls=ff(vend.) Sub=ff Prot=ff Driver=option
 E:  Ad=81(I) Atr=02(Bulk) MxPS= 512 Ivl=0ms
 E:  Ad=01(O) Atr=02(Bulk) MxPS= 512 Ivl=0ms
 I:* If#= 1 Alt= 0 #EPs= 2 Cls=ff(vend.) Sub=42 Prot=01 Driver=(none)
 E:  Ad=82(I) Atr=02(Bulk) MxPS= 512 Ivl=0ms
 E:  Ad=02(O) Atr=02(Bulk) MxPS= 512 Ivl=0ms
 I:* If#= 2 Alt= 0 #EPs= 3 Cls=ff(vend.) Sub=00 Prot=00 Driver=option
 E:  Ad=84(I) Atr=03(Int.) MxPS=  64 Ivl=32ms
 E:  Ad=83(I) Atr=02(Bulk) MxPS= 512 Ivl=0ms
 E:  Ad=03(O) Atr=02(Bulk) MxPS= 512 Ivl=0ms
 I:* If#= 3 Alt= 0 #EPs= 3 Cls=ff(vend.) Sub=ff Prot=ff Driver=qmi_wwan
 E:  Ad=86(I) Atr=03(Int.) MxPS=  64 Ivl=32ms
 E:  Ad=85(I) Atr=02(Bulk) MxPS= 512 Ivl=0ms
 E:  Ad=04(O) Atr=02(Bulk) MxPS= 512 Ivl=0ms
 I:* If#= 4 Alt= 0 #EPs= 3 Cls=ff(vend.) Sub=ff Prot=ff Driver=qmi_wwan
 E:  Ad=88(I) Atr=03(Int.) MxPS=  64 Ivl=32ms
 E:  Ad=87(I) Atr=02(Bulk) MxPS= 512 Ivl=0ms
 I:* If#= 5 Alt= 0 #EPs= 3 Cls=ff(vend.) Sub=ff Prot=ff Driver=qmi_wwan
 E:  Ad=8a(I) Atr=03(Int.) MxPS=  64 Ivl=32ms
 E:  Ad=89(I) Atr=02(Bulk) MxPS= 512 Ivl=0ms
 E:  Ad=06(O) Atr=02(Bulk) MxPS= 512 Ivl=0ms

WNC D18 LTE CAT3 module (1435:d182)

MI_00 Qualcomm HS-USB Diagnostics
MI_01 Androd Debug interface
MI_02 Qualcomm HS-USB Modem
MI_03 Qualcomm HS-USB NMEA
MI_04 Qualcomm Wireless HS-USB Ethernet Adapter
MI_05 Qualcomm Wireless HS-USB Ethernet Adapter
MI_06 USB Mass Storage Device

ZM8510/ZM8620/ME3960 (19d2:0396)

MI_00 ZTE Mobile Broadband Diagnostics Port
MI_01 ZTE Mobile Broadband AT Port
MI_02 ZTE Mobile Broadband Modem
MI_03 ZTE Mobile Broadband NDIS Port (qmi_wwan)
MI_04 ZTE Mobile Broadband ADB Port

ME3620_X (19d2:1432)

MI_00 ZTE Diagnostics Device
MI_01 ZTE UI AT Interface
MI_02 ZTE Modem Device
MI_03 ZTE Mobile Broadband Network Adapter
MI_04 ZTE Composite ADB Interface

Reported-by: Lars Melin <larsm17@gmail.com>
Signed-off-by: Bjørn Mork <bjorn@mork.no>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
5 years agobpf: Fix preempt_enable_no_resched() abuse
Peter Zijlstra [Tue, 23 Apr 2019 19:55:59 +0000 (21:55 +0200)]
bpf: Fix preempt_enable_no_resched() abuse

[ Upstream commit 0edd6b64d1939e9e9168ff27947995bb7751db5d ]

Unless the very next line is schedule(), or implies it, one must not use
preempt_enable_no_resched(). It can cause a preemption to go missing and
thereby cause arbitrary delays, breaking the PREEMPT=y invariant.

Cc: Roman Gushchin <guro@fb.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
5 years agopower: supply: sysfs: prevent endless uevent loop with CONFIG_POWER_SUPPLY_DEBUG
Andrey Smirnov [Wed, 24 Apr 2019 07:16:10 +0000 (00:16 -0700)]
power: supply: sysfs: prevent endless uevent loop with CONFIG_POWER_SUPPLY_DEBUG

[ Upstream commit 349ced9984ff540ce74ca8a0b2e9b03dc434b9dd ]

Fix a similar endless event loop as was done in commit
8dcf32175b4e ("i2c: prevent endless uevent loop with
CONFIG_I2C_DEBUG_CORE"):

  The culprit is the dev_dbg printk in the i2c uevent handler. If
  this is activated (for instance by CONFIG_I2C_DEBUG_CORE) it results
  in an endless loop with systemd-journald.

  This happens if user-space scans the system log and reads the uevent
  file to get information about a newly created device, which seems
  fair use to me. Unfortunately reading the "uevent" file uses the
  same function that runs for creating the uevent for a new device,
  generating the next syslog entry

Both CONFIG_I2C_DEBUG_CORE and CONFIG_POWER_SUPPLY_DEBUG were reported
in https://bugs.freedesktop.org/show_bug.cgi?id=76886 but only former
seems to have been fixed. Drop debug prints as it was done in I2C
subsystem to resolve the issue.

Signed-off-by: Andrey Smirnov <andrew.smirnov@gmail.com>
Cc: Chris Healy <cphealy@gmail.com>
Cc: linux-pm@vger.kernel.org
Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
5 years agoKVM: arm/arm64: Ensure vcpu target is unset on reset failure
Andrew Jones [Thu, 4 Apr 2019 17:42:30 +0000 (19:42 +0200)]
KVM: arm/arm64: Ensure vcpu target is unset on reset failure

[ Upstream commit 811328fc3222f7b55846de0cd0404339e2e1e6d7 ]

A failed KVM_ARM_VCPU_INIT should not set the vcpu target,
as the vcpu target is used by kvm_vcpu_initialized() to
determine if other vcpu ioctls may proceed. We need to set
the target before calling kvm_reset_vcpu(), but if that call
fails, we should then unset it and clear the feature bitmap
while we're at it.

Signed-off-by: Andrew Jones <drjones@redhat.com>
[maz: Simplified patch, completed commit message]
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
5 years agonet: ieee802154: fix missing checks for regmap_update_bits
Kangjie Lu [Sun, 24 Mar 2019 23:18:56 +0000 (18:18 -0500)]
net: ieee802154: fix missing checks for regmap_update_bits

[ Upstream commit 22e8860cf8f777fbf6a83f2fb7127f682a8e9de4 ]

regmap_update_bits could fail and deserves a check.

The patch adds the checks and if it fails, returns its error
code upstream.

Signed-off-by: Kangjie Lu <kjlu@umn.edu>
Reviewed-by: Mukesh Ojha <mojha@codeaurora.org>
Signed-off-by: Stefan Schmidt <stefan@datenfreihafen.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
5 years agomac80211: Fix kernel panic due to use of txq after free
Bhagavathi Perumal S [Tue, 16 Apr 2019 07:24:40 +0000 (12:54 +0530)]
mac80211: Fix kernel panic due to use of txq after free

[ Upstream commit f1267cf3c01b12e0f843fb6a7450a7f0b2efab8a ]

The txq of vif is added to active_txqs list for ATF TXQ scheduling
in the function ieee80211_queue_skb(), but it was not properly removed
before freeing the txq object. It was causing use after free of the txq
objects from the active_txqs list, result was kernel panic
due to invalid memory access.

Fix kernel invalid memory access by properly removing txq object
from active_txqs list before free the object.

Signed-off-by: Bhagavathi Perumal S <bperumal@codeaurora.org>
Acked-by: Toke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
5 years agox86: kvm: hyper-v: deal with buggy TLB flush requests from WS2012
Vitaly Kuznetsov [Wed, 20 Mar 2019 17:43:20 +0000 (18:43 +0100)]
x86: kvm: hyper-v: deal with buggy TLB flush requests from WS2012

[ Upstream commit da66761c2d93a46270d69001abb5692717495a68 ]

It was reported that with some special Multi Processor Group configuration,
e.g:
 bcdedit.exe /set groupsize 1
 bcdedit.exe /set maxgroup on
 bcdedit.exe /set groupaware on
for a 16-vCPU guest WS2012 shows BSOD on boot when PV TLB flush mechanism
is in use.

Tracing kvm_hv_flush_tlb immediately reveals the issue:

 kvm_hv_flush_tlb: processor_mask 0x0 address_space 0x0 flags 0x2

The only flag set in this request is HV_FLUSH_ALL_VIRTUAL_ADDRESS_SPACES,
however, processor_mask is 0x0 and no HV_FLUSH_ALL_PROCESSORS is specified.
We don't flush anything and apparently it's not what Windows expects.

TLFS doesn't say anything about such requests and newer Windows versions
seem to be unaffected. This all feels like a WS2012 bug, which is, however,
easy to workaround in KVM: let's flush everything when we see an empty
flush request, over-flushing doesn't hurt.

Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
5 years agoPCI: Fix issue with "pci=disable_acs_redir" parameter being ignored
Logan Gunthorpe [Wed, 10 Apr 2019 21:05:31 +0000 (15:05 -0600)]
PCI: Fix issue with "pci=disable_acs_redir" parameter being ignored

[ Upstream commit d5bc73f34cc97c4b4b9202cc93182c2515076edf ]

In most cases, kmalloc() will not be available early in boot when
pci_setup() is called.  Thus, the kstrdup() call that was added to fix the
__initdata bug with the disable_acs_redir parameter usually returns NULL,
so the parameter is discarded and has no effect.

To fix this, store the string that's in initdata until an initcall function
can allocate the memory appropriately.  This way we don't need any
additional static memory.

Fixes: d2fd6e81912a ("PCI: Fix __initdata issue with "pci=disable_acs_redir" parameter")
Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
5 years agoapparmorfs: fix use-after-free on symlink traversal
Al Viro [Wed, 10 Apr 2019 18:04:34 +0000 (14:04 -0400)]
apparmorfs: fix use-after-free on symlink traversal

[ Upstream commit f51dcd0f621caac5380ce90fbbeafc32ce4517ae ]

symlink body shouldn't be freed without an RCU delay.  Switch apparmorfs
to ->destroy_inode() and use of call_rcu(); free both the inode and symlink
body in the callback.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
5 years agosecurityfs: fix use-after-free on symlink traversal
Al Viro [Wed, 10 Apr 2019 18:03:45 +0000 (14:03 -0400)]
securityfs: fix use-after-free on symlink traversal

[ Upstream commit 46c874419652bbefdfed17420fd6e88d8a31d9ec ]

symlink body shouldn't be freed without an RCU delay.  Switch securityfs
to ->destroy_inode() and use of call_rcu(); free both the inode and symlink
body in the callback.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
5 years agopower: supply: cpcap-battery: Fix division by zero
Tony Lindgren [Sun, 7 Apr 2019 18:12:48 +0000 (11:12 -0700)]
power: supply: cpcap-battery: Fix division by zero

[ Upstream commit dbe7208c6c4aec083571f2ec742870a0d0edbea3 ]

If called fast enough so samples do not increment, we can get
division by zero in kernel:

__div0
cpcap_battery_cc_raw_div
cpcap_battery_get_property
power_supply_get_property.part.1
power_supply_get_property
power_supply_show_property
power_supply_uevent

Fixes: 874b2adbed12 ("power: supply: cpcap-battery: Add a battery driver")
Signed-off-by: Tony Lindgren <tony@atomide.com>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
5 years agoclk: sunxi-ng: nkmp: Avoid GENMASK(-1, 0)
Jernej Skrabec [Tue, 2 Apr 2019 21:06:21 +0000 (23:06 +0200)]
clk: sunxi-ng: nkmp: Avoid GENMASK(-1, 0)

[ Upstream commit 2abc330c514fe56c570bb1a6318b054b06a4f72e ]

Sometimes one of the nkmp factors is unused. This means that one of the
factors shift and width values are set to 0. Current nkmp clock code
generates a mask for each factor with GENMASK(width + shift - 1, shift).
For unused factor this translates to GENMASK(-1, 0). This code is
further expanded by C preprocessor to final version:
(((~0UL) - (1UL << (0)) + 1) & (~0UL >> (BITS_PER_LONG - 1 - (-1))))
or a bit simplified:
(~0UL & (~0UL >> BITS_PER_LONG))

It turns out that result of the second part (~0UL >> BITS_PER_LONG) is
actually undefined by C standard, which clearly specifies:

"If the value of the right operand is negative or is greater than or
equal to the width of the promoted left operand, the behavior is
undefined."

Additionally, compiling kernel with aarch64-linux-gnu-gcc 8.3.0 gave
different results whether literals or variables with same values as
literals were used. GENMASK with literals -1 and 0 gives zero and with
variables gives 0xFFFFFFFFFFFFFFF (~0UL). Because nkmp driver uses
GENMASK with variables as parameter, expression calculates mask as ~0UL
instead of 0. This has further consequences that LSB in register is
always set to 1 (1 is neutral value for a factor and shift is 0).

For example, H6 pll-de clock is set to 600 MHz by sun4i-drm driver, but
due to this bug ends up being 300 MHz. Additionally, 300 MHz seems to be
too low because following warning can be found in dmesg:

[    1.752763] WARNING: CPU: 2 PID: 41 at drivers/clk/sunxi-ng/ccu_common.c:41 ccu_helper_wait_for_lock.part.0+0x6c/0x90
[    1.763378] Modules linked in:
[    1.766441] CPU: 2 PID: 41 Comm: kworker/2:1 Not tainted 5.1.0-rc2-next-20190401 #138
[    1.774269] Hardware name: Pine H64 (DT)
[    1.778200] Workqueue: events deferred_probe_work_func
[    1.783341] pstate: 40000005 (nZcv daif -PAN -UAO)
[    1.788135] pc : ccu_helper_wait_for_lock.part.0+0x6c/0x90
[    1.793623] lr : ccu_helper_wait_for_lock.part.0+0x48/0x90
[    1.799107] sp : ffff000010f93840
[    1.802422] x29: ffff000010f93840 x28: 0000000000000000
[    1.807735] x27: ffff800073ce9d80 x26: ffff000010afd1b8
[    1.813049] x25: ffffffffffffffff x24: 00000000ffffffff
[    1.818362] x23: 0000000000000001 x22: ffff000010abd5c8
[    1.823675] x21: 0000000010000000 x20: 00000000685f367e
[    1.828987] x19: 0000000000001801 x18: 0000000000000001
[    1.834300] x17: 0000000000000001 x16: 0000000000000000
[    1.839613] x15: 0000000000000000 x14: ffff000010789858
[    1.844926] x13: 0000000000000000 x12: 0000000000000001
[    1.850239] x11: 0000000000000000 x10: 0000000000000970
[    1.855551] x9 : ffff000010f936c0 x8 : ffff800074cec0d0
[    1.860864] x7 : 0000800067117000 x6 : 0000000115c30b41
[    1.866177] x5 : 00ffffffffffffff x4 : 002c959300bfe500
[    1.871490] x3 : 0000000000000018 x2 : 0000000029aaaaab
[    1.876802] x1 : 00000000000002e6 x0 : 00000000686072bc
[    1.882114] Call trace:
[    1.884565]  ccu_helper_wait_for_lock.part.0+0x6c/0x90
[    1.889705]  ccu_helper_wait_for_lock+0x10/0x20
[    1.894236]  ccu_nkmp_set_rate+0x244/0x2a8
[    1.898334]  clk_change_rate+0x144/0x290
[    1.902258]  clk_core_set_rate_nolock+0x180/0x1b8
[    1.906963]  clk_set_rate+0x34/0xa0
[    1.910455]  sun8i_mixer_bind+0x484/0x558
[    1.914466]  component_bind_all+0x10c/0x230
[    1.918651]  sun4i_drv_bind+0xc4/0x1a0
[    1.922401]  try_to_bring_up_master+0x164/0x1c0
[    1.926932]  __component_add+0xa0/0x168
[    1.930769]  component_add+0x10/0x18
[    1.934346]  sun8i_dw_hdmi_probe+0x18/0x20
[    1.938443]  platform_drv_probe+0x50/0xa0
[    1.942455]  really_probe+0xcc/0x280
[    1.946032]  driver_probe_device+0x54/0xe8
[    1.950130]  __device_attach_driver+0x80/0xb8
[    1.954488]  bus_for_each_drv+0x78/0xc8
[    1.958326]  __device_attach+0xd4/0x130
[    1.962163]  device_initial_probe+0x10/0x18
[    1.966348]  bus_probe_device+0x90/0x98
[    1.970185]  deferred_probe_work_func+0x6c/0xa0
[    1.974720]  process_one_work+0x1e0/0x320
[    1.978732]  worker_thread+0x228/0x428
[    1.982484]  kthread+0x120/0x128
[    1.985714]  ret_from_fork+0x10/0x18
[    1.989290] ---[ end trace 9babd42e1ca4b84f ]---

This commit solves the issue by first checking value of the factor
width. If it is equal to 0 (unused factor), mask is set to 0, otherwise
GENMASK() macro is used as before.

Fixes: d897ef56faf9 ("clk: sunxi-ng: Mask nkmp factors when setting register")
Signed-off-by: Jernej Skrabec <jernej.skrabec@siol.net>
Signed-off-by: Maxime Ripard <maxime.ripard@bootlin.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
5 years agoxfrm4: Fix uninitialized memory read in _decode_session4
Steffen Klassert [Tue, 26 Feb 2019 06:04:50 +0000 (07:04 +0100)]
xfrm4: Fix uninitialized memory read in _decode_session4

[ Upstream commit 8742dc86d0c7a9628117a989c11f04a9b6b898f3 ]

We currently don't reload pointers pointing into skb header
after doing pskb_may_pull() in _decode_session4(). So in case
pskb_may_pull() changed the pointers, we read from random
memory. Fix this by putting all the needed infos on the
stack, so that we don't need to access the header pointers
after doing pskb_may_pull().

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
5 years agoxfrm: Honor original L3 slave device in xfrmi policy lookup
Martin Willi [Tue, 26 Mar 2019 12:20:43 +0000 (13:20 +0100)]
xfrm: Honor original L3 slave device in xfrmi policy lookup

[ Upstream commit 025c65e119bf58b610549ca359c9ecc5dee6a8d2 ]

If an xfrmi is associated to a vrf layer 3 master device,
xfrm_policy_check() fails after traffic decapsulation. The input
interface is replaced by the layer 3 master device, and hence
xfrmi_decode_session() can't match the xfrmi anymore to satisfy
policy checking.

Extend ingress xfrmi lookup to honor the original layer 3 slave
device, allowing xfrm interfaces to operate within a vrf domain.

Fixes: f203b76d7809 ("xfrm: Add virtual xfrm interfaces")
Signed-off-by: Martin Willi <martin@strongswan.org>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
5 years agoesp4: add length check for UDP encapsulation
Sabrina Dubroca [Mon, 25 Mar 2019 13:30:00 +0000 (14:30 +0100)]
esp4: add length check for UDP encapsulation

[ Upstream commit 8dfb4eba4100e7cdd161a8baef2d8d61b7a7e62e ]

esp_output_udp_encap can produce a length that doesn't fit in the 16
bits of a UDP header's length field. In that case, we'll send a
fragmented packet whose length is larger than IP_MAX_MTU (resulting in
"Oversized IP packet" warnings on receive) and with a bogus UDP
length.

To prevent this, add a length check to esp_output_udp_encap and return
 -EMSGSIZE on failure.

This seems to be older than git history.

Signed-off-by: Sabrina Dubroca <sd@queasysnail.net>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
5 years agoxfrm: clean up xfrm protocol checks
Cong Wang [Fri, 22 Mar 2019 23:26:19 +0000 (16:26 -0700)]
xfrm: clean up xfrm protocol checks

[ Upstream commit dbb2483b2a46fbaf833cfb5deb5ed9cace9c7399 ]

In commit 6a53b7593233 ("xfrm: check id proto in validate_tmpl()")
I introduced a check for xfrm protocol, but according to Herbert
IPSEC_PROTO_ANY should only be used as a wildcard for lookup, so
it should be removed from validate_tmpl().

And, IPSEC_PROTO_ANY is expected to only match 3 IPSec-specific
protocols, this is why xfrm_state_flush() could still miss
IPPROTO_ROUTING, which leads that those entries are left in
net->xfrm.state_all before exit net. Fix this by replacing
IPSEC_PROTO_ANY with zero.

This patch also extracts the check from validate_tmpl() to
xfrm_id_proto_valid() and uses it in parse_ipsecrequest().
With this, no other protocols should be added into xfrm.

Fixes: 6a53b7593233 ("xfrm: check id proto in validate_tmpl()")
Reported-by: syzbot+0bf0519d6e0de15914fe@syzkaller.appspotmail.com
Cc: Steffen Klassert <steffen.klassert@secunet.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
5 years agovti4: ipip tunnel deregistration fixes.
Jeremy Sowden [Tue, 19 Mar 2019 15:39:20 +0000 (15:39 +0000)]
vti4: ipip tunnel deregistration fixes.

[ Upstream commit 5483844c3fc18474de29f5d6733003526e0a9f78 ]

If tunnel registration failed during module initialization, the module
would fail to deregister the IPPROTO_COMP protocol and would attempt to
deregister the tunnel.

The tunnel was not deregistered during module-exit.

Fixes: dd9ee3444014e ("vti4: Fix a ipip packet processing bug in 'IPCOMP' virtual tunnel")
Signed-off-by: Jeremy Sowden <jeremy@azazel.net>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
5 years agoxfrm6_tunnel: Fix potential panic when unloading xfrm6_tunnel module
Su Yanjun [Thu, 14 Mar 2019 06:59:42 +0000 (14:59 +0800)]
xfrm6_tunnel: Fix potential panic when unloading xfrm6_tunnel module

[ Upstream commit 6ee02a54ef990a71bf542b6f0a4e3321de9d9c66 ]

When unloading xfrm6_tunnel module, xfrm6_tunnel_fini directly
frees the xfrm6_tunnel_spi_kmem. Maybe someone has gotten the
xfrm6_tunnel_spi, so need to wait it.

Fixes: 91cc3bb0b04ff("xfrm6_tunnel: RCU conversion")
Signed-off-by: Su Yanjun <suyj.fnst@cn.fujitsu.com>
Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
5 years agoxfrm: policy: Fix out-of-bound array accesses in __xfrm_policy_unlink
YueHaibing [Thu, 28 Feb 2019 07:18:59 +0000 (15:18 +0800)]
xfrm: policy: Fix out-of-bound array accesses in __xfrm_policy_unlink

[ Upstream commit b805d78d300bcf2c83d6df7da0c818b0fee41427 ]

UBSAN report this:

UBSAN: Undefined behaviour in net/xfrm/xfrm_policy.c:1289:24
index 6 is out of range for type 'unsigned int [6]'
CPU: 1 PID: 0 Comm: swapper/1 Not tainted 4.4.162-514.55.6.9.x86_64+ #13
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1ubuntu1 04/01/2014
 0000000000000000 1466cf39b41b23c9 ffff8801f6b07a58 ffffffff81cb35f4
 0000000041b58ab3 ffffffff83230f9c ffffffff81cb34e0 ffff8801f6b07a80
 ffff8801f6b07a20 1466cf39b41b23c9 ffffffff851706e0 ffff8801f6b07ae8
Call Trace:
 <IRQ>  [<ffffffff81cb35f4>] __dump_stack lib/dump_stack.c:15 [inline]
 <IRQ>  [<ffffffff81cb35f4>] dump_stack+0x114/0x1a0 lib/dump_stack.c:51
 [<ffffffff81d94225>] ubsan_epilogue+0x12/0x8f lib/ubsan.c:164
 [<ffffffff81d954db>] __ubsan_handle_out_of_bounds+0x16e/0x1b2 lib/ubsan.c:382
 [<ffffffff82a25acd>] __xfrm_policy_unlink+0x3dd/0x5b0 net/xfrm/xfrm_policy.c:1289
 [<ffffffff82a2e572>] xfrm_policy_delete+0x52/0xb0 net/xfrm/xfrm_policy.c:1309
 [<ffffffff82a3319b>] xfrm_policy_timer+0x30b/0x590 net/xfrm/xfrm_policy.c:243
 [<ffffffff813d3927>] call_timer_fn+0x237/0x990 kernel/time/timer.c:1144
 [<ffffffff813d8e7e>] __run_timers kernel/time/timer.c:1218 [inline]
 [<ffffffff813d8e7e>] run_timer_softirq+0x6ce/0xb80 kernel/time/timer.c:1401
 [<ffffffff8120d6f9>] __do_softirq+0x299/0xe10 kernel/softirq.c:273
 [<ffffffff8120e676>] invoke_softirq kernel/softirq.c:350 [inline]
 [<ffffffff8120e676>] irq_exit+0x216/0x2c0 kernel/softirq.c:391
 [<ffffffff82c5edab>] exiting_irq arch/x86/include/asm/apic.h:652 [inline]
 [<ffffffff82c5edab>] smp_apic_timer_interrupt+0x8b/0xc0 arch/x86/kernel/apic/apic.c:926
 [<ffffffff82c5c985>] apic_timer_interrupt+0xa5/0xb0 arch/x86/entry/entry_64.S:735
 <EOI>  [<ffffffff81188096>] ? native_safe_halt+0x6/0x10 arch/x86/include/asm/irqflags.h:52
 [<ffffffff810834d7>] arch_safe_halt arch/x86/include/asm/paravirt.h:111 [inline]
 [<ffffffff810834d7>] default_idle+0x27/0x430 arch/x86/kernel/process.c:446
 [<ffffffff81085f05>] arch_cpu_idle+0x15/0x20 arch/x86/kernel/process.c:437
 [<ffffffff8132abc3>] default_idle_call+0x53/0x90 kernel/sched/idle.c:92
 [<ffffffff8132b32d>] cpuidle_idle_call kernel/sched/idle.c:156 [inline]
 [<ffffffff8132b32d>] cpu_idle_loop kernel/sched/idle.c:251 [inline]
 [<ffffffff8132b32d>] cpu_startup_entry+0x60d/0x9a0 kernel/sched/idle.c:299
 [<ffffffff8113e119>] start_secondary+0x3c9/0x560 arch/x86/kernel/smpboot.c:245

The issue is triggered as this:

xfrm_add_policy
    -->verify_newpolicy_info  //check the index provided by user with XFRM_POLICY_MAX
      //In my case, the index is 0x6E6BB6, so it pass the check.
    -->xfrm_policy_construct  //copy the user's policy and set xfrm_policy_timer
    -->xfrm_policy_insert
--> __xfrm_policy_link //use the orgin dir, in my case is 2
--> xfrm_gen_index   //generate policy index, there is 0x6E6BB6

then xfrm_policy_timer be fired

xfrm_policy_timer
   --> xfrm_policy_id2dir  //get dir from (policy index & 7), in my case is 6
   --> xfrm_policy_delete
      --> __xfrm_policy_unlink //access policy_count[dir], trigger out of range access

Add xfrm_policy_id2dir check in verify_newpolicy_info, make sure the computed dir is
valid, to fix the issue.

Reported-by: Hulk Robot <hulkci@huawei.com>
Fixes: e682adf021be ("xfrm: Try to honor policy index if it's supplied by user")
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
5 years agofuse: Add FOPEN_STREAM to use stream_open()
Kirill Smelkov [Wed, 24 Apr 2019 07:13:57 +0000 (07:13 +0000)]
fuse: Add FOPEN_STREAM to use stream_open()

commit bbd84f33652f852ce5992d65db4d020aba21f882 upstream.

Starting from commit 9c225f2655e3 ("vfs: atomic f_pos accesses as per
POSIX") files opened even via nonseekable_open gate read and write via lock
and do not allow them to be run simultaneously. This can create read vs
write deadlock if a filesystem is trying to implement a socket-like file
which is intended to be simultaneously used for both read and write from
filesystem client.  See commit 10dce8af3422 ("fs: stream_open - opener for
stream-like files so that read and write can run simultaneously without
deadlock") for details and e.g. commit 581d21a2d02a ("xenbus: fix deadlock
on writes to /proc/xen/xenbus") for a similar deadlock example on
/proc/xen/xenbus.

To avoid such deadlock it was tempting to adjust fuse_finish_open to use
stream_open instead of nonseekable_open on just FOPEN_NONSEEKABLE flags,
but grepping through Debian codesearch shows users of FOPEN_NONSEEKABLE,
and in particular GVFS which actually uses offset in its read and write
handlers

https://codesearch.debian.net/search?q=-%3Enonseekable+%3D
https://gitlab.gnome.org/GNOME/gvfs/blob/1.40.0-6-gcbc54396/client/gvfsfusedaemon.c#L1080
https://gitlab.gnome.org/GNOME/gvfs/blob/1.40.0-6-gcbc54396/client/gvfsfusedaemon.c#L1247-1346
https://gitlab.gnome.org/GNOME/gvfs/blob/1.40.0-6-gcbc54396/client/gvfsfusedaemon.c#L1399-1481

so if we would do such a change it will break a real user.

Add another flag (FOPEN_STREAM) for filesystem servers to indicate that the
opened handler is having stream-like semantics; does not use file position
and thus the kernel is free to issue simultaneous read and write request on
opened file handle.

This patch together with stream_open() should be added to stable kernels
starting from v3.14+. This will allow to patch OSSPD and other FUSE
filesystems that provide stream-like files to return FOPEN_STREAM |
FOPEN_NONSEEKABLE in open handler and this way avoid the deadlock on all
kernel versions. This should work because fuse_finish_open ignores unknown
open flags returned from a filesystem and so passing FOPEN_STREAM to a
kernel that is not aware of this flag cannot hurt. In turn the kernel that
is not aware of FOPEN_STREAM will be < v3.14 where just FOPEN_NONSEEKABLE
is sufficient to implement streams without read vs write deadlock.

Cc: stable@vger.kernel.org # v3.14+
Signed-off-by: Kirill Smelkov <kirr@nexedi.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
5 years agodm mpath: always free attached_handler_name in parse_path()
Martin Wilck [Mon, 29 Apr 2019 09:48:15 +0000 (11:48 +0200)]
dm mpath: always free attached_handler_name in parse_path()

commit 940bc471780b004a5277c1931f52af363c2fc9da upstream.

Commit b592211c33f7 ("dm mpath: fix attached_handler_name leak and
dangling hw_handler_name pointer") fixed a memory leak for the case
where setup_scsi_dh() returns failure. But setup_scsi_dh may return
success and not "use" attached_handler_name if the
retain_attached_hwhandler flag is not set on the map. As setup_scsi_sh
properly "steals" the pointer by nullifying it, freeing it
unconditionally in parse_path() is safe.

Fixes: b592211c33f7 ("dm mpath: fix attached_handler_name leak and dangling hw_handler_name pointer")
Cc: stable@vger.kernel.org
Reported-by: Yufen Yu <yuyufen@huawei.com>
Signed-off-by: Martin Wilck <mwilck@suse.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
5 years agodm integrity: correctly calculate the size of metadata area
Mikulas Patocka [Tue, 7 May 2019 18:28:35 +0000 (14:28 -0400)]
dm integrity: correctly calculate the size of metadata area

commit 30bba430ddf737978e40561198693ba91386dac1 upstream.

When we use separate devices for data and metadata, dm-integrity would
incorrectly calculate the size of the metadata device as if it had
512-byte block size - and it would refuse activation with larger block
size and smaller metadata device.

Fix this so that it takes actual block size into account, which fixes
the following reported issue:
https://gitlab.com/cryptsetup/cryptsetup/issues/450

Fixes: 356d9d52e122 ("dm integrity: allow separate metadata device")
Cc: stable@vger.kernel.org # v4.19+
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
5 years agodm delay: fix a crash when invalid device is specified
Mikulas Patocka [Thu, 25 Apr 2019 16:07:54 +0000 (12:07 -0400)]
dm delay: fix a crash when invalid device is specified

commit 81bc6d150ace6250503b825d9d0c10f7bbd24095 upstream.

When the target line contains an invalid device, delay_ctr() will call
delay_dtr() with NULL workqueue.  Attempting to destroy the NULL
workqueue causes a crash.

Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
5 years agodm zoned: Fix zone report handling
Damien Le Moal [Thu, 18 Apr 2019 09:03:07 +0000 (18:03 +0900)]
dm zoned: Fix zone report handling

commit 7aedf75ff740a98f3683439449cd91c8662d03b2 upstream.

The function blkdev_report_zones() returns success even if no zone
information is reported (empty report). Empty zone reports can only
happen if the report start sector passed exceeds the device capacity.
The conditions for this to happen are either a bug in the caller code,
or, a change in the device that forced the low level driver to change
the device capacity to a value that is lower than the report start
sector. This situation includes a failed disk revalidation resulting in
the disk capacity being changed to 0.

If this change happens while dm-zoned is in its initialization phase
executing dmz_init_zones(), this function may enter an infinite loop
and hang the system. To avoid this, add a check to disallow empty zone
reports and bail out early. Also fix the function dmz_update_zone() to
make sure that the report for the requested zone was correctly obtained.

Fixes: 3b1a94c88b79 ("dm zoned: drive-managed zoned block device target")
Cc: stable@vger.kernel.org
Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com>
Reviewed-by: Shaun Tancheff <shaun@tancheff.com>
Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
5 years agodm cache metadata: Fix loading discard bitset
Nikos Tsironis [Wed, 17 Apr 2019 14:19:18 +0000 (17:19 +0300)]
dm cache metadata: Fix loading discard bitset

commit e28adc3bf34e434b30e8d063df4823ba0f3e0529 upstream.

Add missing dm_bitset_cursor_next() to properly advance the bitset
cursor.

Otherwise, the discarded state of all blocks is set according to the
discarded state of the first block.

Fixes: ae4a46a1f6 ("dm cache metadata: use bitset cursor api to load discard bitset")
Cc: stable@vger.kernel.org
Signed-off-by: Nikos Tsironis <ntsironis@arrikto.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
5 years agoPCI: Work around Pericom PCIe-to-PCI bridge Retrain Link erratum
Stefan Mätje [Fri, 29 Mar 2019 17:07:35 +0000 (18:07 +0100)]
PCI: Work around Pericom PCIe-to-PCI bridge Retrain Link erratum

commit 4ec73791a64bab25cabf16a6067ee478692e506d upstream.

Due to an erratum in some Pericom PCIe-to-PCI bridges in reverse mode
(conventional PCI on primary side, PCIe on downstream side), the Retrain
Link bit needs to be cleared manually to allow the link training to
complete successfully.

If it is not cleared manually, the link training is continuously restarted
and no devices below the PCI-to-PCIe bridge can be accessed.  That means
drivers for devices below the bridge will be loaded but won't work and may
even crash because the driver is only reading 0xffff.

See the Pericom Errata Sheet PI7C9X111SLB_errata_rev1.2_102711.pdf for
details.  Devices known as affected so far are: PI7C9X110, PI7C9X111SL,
PI7C9X130.

Add a new flag, clear_retrain_link, in struct pci_dev.  Quirks for affected
devices set this bit.

Note that pcie_retrain_link() lives in aspm.c because that's currently the
only place we use it, but this erratum is not specific to ASPM, and we may
retrain links for other reasons in the future.

Signed-off-by: Stefan Mätje <stefan.maetje@esd.eu>
[bhelgaas: apply regardless of CONFIG_PCIEASPM]
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
CC: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
5 years agoPCI: Factor out pcie_retrain_link() function
Stefan Mätje [Fri, 29 Mar 2019 17:07:34 +0000 (18:07 +0100)]
PCI: Factor out pcie_retrain_link() function

commit 86fa6a344209d9414ea962b1f1ac6ade9dd7563a upstream.

Factor out pcie_retrain_link() to use for Pericom Retrain Link quirk.  No
functional change intended.

Signed-off-by: Stefan Mätje <stefan.maetje@esd.eu>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
CC: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
5 years agoPCI: rcar: Add the initialization of PCIe link in resume_noirq()
Kazufumi Ikeda [Mon, 25 Mar 2019 19:43:19 +0000 (20:43 +0100)]
PCI: rcar: Add the initialization of PCIe link in resume_noirq()

commit be20bbcb0a8cb5597cc62b3e28d275919f3431df upstream.

Reestablish the PCIe link very early in the resume process in case it
went down to prevent PCI accesses from hanging the bus. Such accesses
can happen early in the PCI resume process, as early as the
SUSPEND_RESUME_NOIRQ step, thus the link must be reestablished in the
driver resume_noirq() callback.

Fixes: e015f88c368d ("PCI: rcar: Add support for R-Car H3 to pcie-rcar")
Signed-off-by: Kazufumi Ikeda <kaz-ikeda@xc.jp.nec.com>
Signed-off-by: Gaku Inami <gaku.inami.xw@bp.renesas.com>
Signed-off-by: Marek Vasut <marek.vasut+renesas@gmail.com>
[lorenzo.pieralisi@arm.com: reformatted commit log]
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Reviewed-by: Simon Horman <horms+renesas@verge.net.au>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Cc: stable@vger.kernel.org
Cc: Geert Uytterhoeven <geert+renesas@glider.be>
Cc: Phil Edworthy <phil.edworthy@renesas.com>
Cc: Simon Horman <horms+renesas@verge.net.au>
Cc: Wolfram Sang <wsa@the-dreams.de>
Cc: linux-renesas-soc@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
5 years agoPCI/AER: Change pci_aer_init() stub to return void
Jisheng Zhang [Fri, 12 Apr 2019 06:43:06 +0000 (06:43 +0000)]
PCI/AER: Change pci_aer_init() stub to return void

commit 31f996efbd5a7825f4d30150469e9d110aea00e8 upstream.

Commit 60ed982a4e78 ("PCI/AER: Move internal declarations to
drivers/pci/pci.h") changed pci_aer_init() to return "void", but didn't
change the stub for when CONFIG_PCIEAER isn't enabled.  Change the stub to
match.

Fixes: 60ed982a4e78 ("PCI/AER: Move internal declarations to drivers/pci/pci.h")
Signed-off-by: Jisheng Zhang <Jisheng.Zhang@synaptics.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
CC: stable@vger.kernel.org # v4.19+
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
5 years agoPCI: Init PCIe feature bits for managed host bridge alloc
Jean-Philippe Brucker [Mon, 18 Mar 2019 16:07:18 +0000 (16:07 +0000)]
PCI: Init PCIe feature bits for managed host bridge alloc

commit 6302bf3ef78dd210b5ff4a922afcb7d8eff8a211 upstream.

Two functions allocate a host bridge: devm_pci_alloc_host_bridge() and
pci_alloc_host_bridge().  At the moment, only the unmanaged one initializes
the PCIe feature bits, which prevents from using features such as hotplug
or AER on some systems, when booting with device tree.  Make the
initialization code common.

Fixes: 02bfeb484230 ("PCI/portdrv: Simplify PCIe feature permission checking")
Signed-off-by: Jean-Philippe Brucker <jean-philippe.brucker@arm.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
CC: stable@vger.kernel.org # v4.17+
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
5 years agoPCI: Mark Atheros AR9462 to avoid bus reset
James Prestwood [Mon, 7 Jan 2019 21:32:48 +0000 (13:32 -0800)]
PCI: Mark Atheros AR9462 to avoid bus reset

commit 6afb7e26978da5e86e57e540fdce65c8b04f398a upstream.

When using PCI passthrough with this device, the host machine locks up
completely when starting the VM, requiring a hard reboot.  Add a quirk to
avoid bus resets on this device.

Fixes: c3e59ee4e766 ("PCI: Mark Atheros AR93xx to avoid bus reset")
Link: https://lore.kernel.org/linux-pci/20190107213248.3034-1-james.prestwood@linux.intel.com
Signed-off-by: James Prestwood <james.prestwood@linux.intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
CC: stable@vger.kernel.org # v3.14+
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
5 years agoPCI: Mark AMD Stoney Radeon R7 GPU ATS as broken
Nikolai Kostrigin [Mon, 8 Apr 2019 10:37:25 +0000 (13:37 +0300)]
PCI: Mark AMD Stoney Radeon R7 GPU ATS as broken

commit d28ca864c493637f3c957f4ed9348a94fca6de60 upstream.

ATS is broken on the Radeon R7 GPU (at least for Stoney Ridge based laptop)
and causes IOMMU stalls and system failure.  Disable ATS on these devices
to make them usable again with IOMMU enabled.

Thanks to Joerg Roedel <jroedel@suse.de> for help.

[bhelgaas: In the email thread mentioned below, Alex suspects the real
problem is in sbios or iommu, so it may affect only certain systems, and it
may affect other devices in those systems as well.  However, per Joerg we
lack the ability to debug further, so this quirk is the best we can do for
now.]

Link: https://bugzilla.kernel.org/show_bug.cgi?id=194521
Link: https://lore.kernel.org/lkml/20190408103725.30426-1-nickel@altlinux.org
Fixes: 9b44b0b09dec ("PCI: Mark AMD Stoney GPU ATS as broken")
Signed-off-by: Nikolai Kostrigin <nickel@altlinux.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Joerg Roedel <jroedel@suse.de>
CC: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
5 years agofbdev: sm712fb: fix crashes and garbled display during DPMS modesetting
Yifeng Li [Mon, 1 Apr 2019 15:46:59 +0000 (17:46 +0200)]
fbdev: sm712fb: fix crashes and garbled display during DPMS modesetting

commit f627caf55b8e735dcec8fa6538e9668632b55276 upstream.

On a Thinkpad s30 (Pentium III / i440MX, Lynx3DM), blanking the display
or starting the X server will crash and freeze the system, or garble the
display.

Experiments showed this problem can mostly be solved by adjusting the
order of register writes. Also, sm712fb failed to consider the difference
of clock frequency when unblanking the display, and programs the clock for
SM712 to SM720.

Fix them by adjusting the order of register writes, and adding an
additional check for SM720 for programming the clock frequency.

Signed-off-by: Yifeng Li <tomli@tomli.me>
Tested-by: Sudip Mukherjee <sudipm.mukherjee@gmail.com>
Cc: Teddy Wang <teddy.wang@siliconmotion.com>
Cc: <stable@vger.kernel.org> # v4.4+
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
5 years agofbdev: sm712fb: use 1024x768 by default on non-MIPS, fix garbled display
Yifeng Li [Mon, 1 Apr 2019 15:46:59 +0000 (17:46 +0200)]
fbdev: sm712fb: use 1024x768 by default on non-MIPS, fix garbled display

commit 4ed7d2ccb7684510ec5f7a8f7ef534bc6a3d55b2 upstream.

Loongson MIPS netbooks use 1024x600 LCD panels, which is the original
target platform of this driver, but nearly all old x86 laptops have
1024x768. Lighting 768 panels using 600's timings would partially
garble the display. Since it's not possible to distinguish them reliably,
we change the default to 768, but keep 600 as-is on MIPS.

Further, earlier laptops, such as IBM Thinkpad 240X, has a 800x600 LCD
panel, this driver would probably garbled those display. As we don't
have one for testing, the original behavior of the driver is kept as-is,
but the problem has been documented is the comments.

Signed-off-by: Yifeng Li <tomli@tomli.me>
Tested-by: Sudip Mukherjee <sudipm.mukherjee@gmail.com>
Cc: Teddy Wang <teddy.wang@siliconmotion.com>
Cc: <stable@vger.kernel.org> # v4.4+
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
5 years agofbdev: sm712fb: fix support for 1024x768-16 mode
Yifeng Li [Mon, 1 Apr 2019 15:46:59 +0000 (17:46 +0200)]
fbdev: sm712fb: fix support for 1024x768-16 mode

commit 6053d3a4793e5bde6299ac5388e76a3bf679ff65 upstream.

In order to support the 1024x600 panel on Yeeloong Loongson MIPS
laptop, the original 1024x768-16 table was modified to 1024x600-16,
without leaving the original. It causes problem on x86 laptop as
the 1024x768-16 support was still claimed but not working.

Fix it by introducing the 1024x768-16 mode.

Signed-off-by: Yifeng Li <tomli@tomli.me>
Tested-by: Sudip Mukherjee <sudipm.mukherjee@gmail.com>
Cc: Teddy Wang <teddy.wang@siliconmotion.com>
Cc: <stable@vger.kernel.org> # v4.4+
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
5 years agofbdev: sm712fb: fix crashes during framebuffer writes by correctly mapping VRAM
Yifeng Li [Mon, 1 Apr 2019 15:46:59 +0000 (17:46 +0200)]
fbdev: sm712fb: fix crashes during framebuffer writes by correctly mapping VRAM

commit 9e0e59993df0601cddb95c4f6c61aa3d5e753c00 upstream.

On a Thinkpad s30 (Pentium III / i440MX, Lynx3DM), running fbtest or X
will crash the machine instantly, because the VRAM/framebuffer is not
mapped correctly.

On SM712, the framebuffer starts at the beginning of address space, but
SM720's framebuffer starts at the 1 MiB offset from the beginning. However,
sm712fb fails to take this into account, as a result, writing to the
framebuffer will destroy all the registers and kill the system immediately.
Another problem is the driver assumes 8 MiB of VRAM for SM720, but some
SM720 system, such as this IBM Thinkpad, only has 4 MiB of VRAM.

Fix this problem by removing the hardcoded VRAM size, adding a function to
query the amount of VRAM from register MCR76 on SM720, and adding proper
framebuffer offset.

Please note that the memory map may have additional problems on Big-Endian
system, which is not available for testing by myself. But I highly suspect
that the original code is also broken on Big-Endian machines for SM720, so
at least we are not making the problem worse. More, the driver also assumed
SM710/SM712 has 4 MiB of VRAM, but it has a 2 MiB version as well, and used
in earlier laptops, such as IBM Thinkpad 240X, the driver would probably
crash on them. I've never seen one of those machines and cannot fix it, but
I have documented these problems in the comments.

Signed-off-by: Yifeng Li <tomli@tomli.me>
Tested-by: Sudip Mukherjee <sudipm.mukherjee@gmail.com>
Cc: Teddy Wang <teddy.wang@siliconmotion.com>
Cc: <stable@vger.kernel.org> # v4.4+
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
5 years agofbdev: sm712fb: fix boot screen glitch when sm712fb replaces VGA
Yifeng Li [Mon, 1 Apr 2019 15:46:59 +0000 (17:46 +0200)]
fbdev: sm712fb: fix boot screen glitch when sm712fb replaces VGA

commit ec1587d5073f29820e358f3a383850d61601d981 upstream.

When the machine is booted in VGA mode, loading sm712fb would cause
a glitch of random pixels shown on the screen. To prevent it from
happening, we first clear the entire framebuffer, and we also need
to stop calling smtcfb_setmode() during initialization, the fbdev
layer will call it for us later when it's ready.

Signed-off-by: Yifeng Li <tomli@tomli.me>
Tested-by: Sudip Mukherjee <sudipm.mukherjee@gmail.com>
Cc: Teddy Wang <teddy.wang@siliconmotion.com>
Cc: <stable@vger.kernel.org> # v4.4+
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
5 years agofbdev: sm712fb: fix white screen of death on reboot, don't set CR3B-CR3F
Yifeng Li [Mon, 1 Apr 2019 15:46:58 +0000 (17:46 +0200)]
fbdev: sm712fb: fix white screen of death on reboot, don't set CR3B-CR3F

commit 8069053880e0ee3a75fd6d7e0a30293265fe3de4 upstream.

On a Thinkpad s30 (Pentium III / i440MX, Lynx3DM), rebooting with
sm712fb framebuffer driver would cause a white screen of death on
the next POST, presumably the proper timings for the LCD panel was
not reprogrammed properly by the BIOS.

Experiments showed a few CRTC Scratch Registers, including CRT3D,
CRT3E and CRT3F may be used internally by BIOS as some flags. CRT3B is
a hardware testing register, we shouldn't mess with it. CRT3C has
blanking signal and line compare control, which is not needed for this
driver.

Stop writing to CR3B-CR3F (a.k.a CRT3B-CRT3F) registers. Even if these
registers don't have side-effect on other systems, writing to them is
also highly questionable.

Signed-off-by: Yifeng Li <tomli@tomli.me>
Tested-by: Sudip Mukherjee <sudipm.mukherjee@gmail.com>
Cc: Teddy Wang <teddy.wang@siliconmotion.com>
Cc: <stable@vger.kernel.org> # v4.4+
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
5 years agofbdev: sm712fb: fix VRAM detection, don't set SR70/71/74/75
Yifeng Li [Mon, 1 Apr 2019 15:46:58 +0000 (17:46 +0200)]
fbdev: sm712fb: fix VRAM detection, don't set SR70/71/74/75

commit dcf9070595e100942c539e229dde4770aaeaa4e9 upstream.

On a Thinkpad s30 (Pentium III / i440MX, Lynx3DM), the amount of Video
RAM is not detected correctly by the xf86-video-siliconmotion driver.
This is because sm712fb overwrites the GPR71 Scratch Pad Register, which
is set by BIOS on x86 and used to indicate amount of VRAM.

Other Scratch Pad Registers, including GPR70/74/75, don't have the same
side-effect, but overwriting to them is still questionable, as they are
not related to modesetting.

Stop writing to SR70/71/74/75 (a.k.a GPR70/71/74/75).

Signed-off-by: Yifeng Li <tomli@tomli.me>
Tested-by: Sudip Mukherjee <sudipm.mukherjee@gmail.com>
Cc: Teddy Wang <teddy.wang@siliconmotion.com>
Cc: <stable@vger.kernel.org> # v4.4+
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
5 years agofbdev: sm712fb: fix brightness control on reboot, don't set SR30
Yifeng Li [Mon, 1 Apr 2019 15:46:58 +0000 (17:46 +0200)]
fbdev: sm712fb: fix brightness control on reboot, don't set SR30

commit 5481115e25e42b9215f2619452aa99c95f08492f upstream.

On a Thinkpad s30 (Pentium III / i440MX, Lynx3DM), rebooting with
sm712fb framebuffer driver would cause the role of brightness up/down
button to swap.

Experiments showed the FPR30 register caused this behavior. Moreover,
even if this register don't have side-effect on other systems, over-
writing it is also highly questionable, since it was originally
configurated by the motherboard manufacturer by hardwiring pull-down
resistors to indicate the type of LCD panel. We should not mess with
it.

Stop writing to the SR30 (a.k.a FPR30) register.

Signed-off-by: Yifeng Li <tomli@tomli.me>
Tested-by: Sudip Mukherjee <sudipm.mukherjee@gmail.com>
Cc: Teddy Wang <teddy.wang@siliconmotion.com>
Cc: <stable@vger.kernel.org> # v4.4+
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
5 years agofbdev/efifb: Ignore framebuffer memmap entries that lack any memory types
Ard Biesheuvel [Thu, 16 May 2019 21:31:59 +0000 (23:31 +0200)]
fbdev/efifb: Ignore framebuffer memmap entries that lack any memory types

commit f8585539df0a1527c78b5d760665c89fe1c105a9 upstream.

The following commit:

  38ac0287b7f4 ("fbdev/efifb: Honour UEFI memory map attributes when mapping the FB")

updated the EFI framebuffer code to use memory mappings for the linear
framebuffer that are permitted by the memory attributes described by the
EFI memory map for the particular region, if the framebuffer happens to
be covered by the EFI memory map (which is typically only the case for
framebuffers in shared memory). This is required since non-x86 systems
may require cacheable attributes for memory mappings that are shared
with other masters (such as GPUs), and this information cannot be
described by the Graphics Output Protocol (GOP) EFI protocol itself,
and so we rely on the EFI memory map for this.

As reported by James, this breaks some x86 systems:

  [ 1.173368] efifb: probing for efifb
  [ 1.173386] efifb: abort, cannot remap video memory 0x1d5000 @ 0xcf800000
  [ 1.173395] Trying to free nonexistent resource <00000000cf800000-00000000cf9d4bff>
  [ 1.173413] efi-framebuffer: probe of efi-framebuffer.0 failed with error -5

The problem turns out to be that the memory map entry that describes the
framebuffer has no memory attributes listed at all, and so we end up with
a mem_flags value of 0x0.

So work around this by ensuring that the memory map entry's attribute field
has a sane value before using it to mask the set of usable attributes.

Reported-by: James Hilliard <james.hilliard1@gmail.com>
Tested-by: James Hilliard <james.hilliard1@gmail.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: <stable@vger.kernel.org> # v4.19+
Cc: Borislav Petkov <bp@alien8.de>
Cc: James Morse <james.morse@arm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Peter Jones <pjones@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Fixes: 38ac0287b7f4 ("fbdev/efifb: Honour UEFI memory map attributes when ...")
Link: http://lkml.kernel.org/r/20190516213159.3530-2-ard.biesheuvel@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
5 years agoobjtool: Allow AR to be overridden with HOSTAR
Nathan Chancellor [Thu, 16 May 2019 17:49:42 +0000 (12:49 -0500)]
objtool: Allow AR to be overridden with HOSTAR

commit 8ea58f1e8b11cca3087b294779bf5959bf89cc10 upstream.

Currently, this Makefile hardcodes GNU ar, meaning that if it is not
available, there is no way to supply a different one and the build will
fail.

  $ make AR=llvm-ar CC=clang LD=ld.lld HOSTAR=llvm-ar HOSTCC=clang \
         HOSTLD=ld.lld HOSTLDFLAGS=-fuse-ld=lld defconfig modules_prepare
  ...
    AR       /out/tools/objtool/libsubcmd.a
  /bin/sh: 1: ar: not found
  ...

Follow the logic of HOST{CC,LD} and allow the user to specify a
different ar tool via HOSTAR (which is used elsewhere in other
tools/ Makefiles).

Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Reviewed-by: Mukesh Ojha <mojha@codeaurora.org>
Cc: <stable@vger.kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/80822a9353926c38fd7a152991c6292491a9d0e8.1558028966.git.jpoimboe@redhat.com
Link: https://github.com/ClangBuiltLinux/linux/issues/481
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
5 years agoMIPS: perf: Fix build with CONFIG_CPU_BMIPS5000 enabled
Florian Fainelli [Thu, 9 May 2019 18:30:47 +0000 (11:30 -0700)]
MIPS: perf: Fix build with CONFIG_CPU_BMIPS5000 enabled

commit 1b1f01b653b408ebe58fec78c566d1075d285c64 upstream.

arch/mips/kernel/perf_event_mipsxx.c: In function 'mipsxx_pmu_enable_event':
arch/mips/kernel/perf_event_mipsxx.c:326:21: error: unused variable 'event' [-Werror=unused-variable]
  struct perf_event *event = container_of(evt, struct perf_event, hw);
                     ^~~~~

Fix this by making use of IS_ENABLED() to simplify the code and avoid
unnecessary ifdefery.

Fixes: 84002c88599d ("MIPS: perf: Fix perf with MT counting other threads")
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Paul Burton <paul.burton@mips.com>
Cc: linux-mips@linux-mips.org
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: James Hogan <jhogan@kernel.org>
Cc: linux-kernel@vger.kernel.org
Cc: linux-mips@vger.kernel.org
Cc: stable@vger.kernel.org # v4.18+
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
5 years agoperf intel-pt: Fix sample timestamp wrt non-taken branches
Adrian Hunter [Fri, 10 May 2019 12:41:43 +0000 (15:41 +0300)]
perf intel-pt: Fix sample timestamp wrt non-taken branches

commit 1b6599a9d8e6c9f7e9b0476012383b1777f7fc93 upstream.

The sample timestamp is updated to ensure that the timestamp represents
the time of the sample and not a branch that the decoder is still
walking towards. The sample timestamp is updated when the decoder
returns, but the decoder does not return for non-taken branches. Update
the sample timestamp then also.

Note that commit 3f04d98e972b5 ("perf intel-pt: Improve sample
timestamp") was also a stable fix and appears, for example, in v4.4
stable tree as commit a4ebb58fd124 ("perf intel-pt: Improve sample
timestamp").

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: stable@vger.kernel.org # v4.4+
Fixes: 3f04d98e972b ("perf intel-pt: Improve sample timestamp")
Link: http://lkml.kernel.org/r/20190510124143.27054-4-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
5 years agoperf intel-pt: Fix improved sample timestamp
Adrian Hunter [Fri, 10 May 2019 12:41:42 +0000 (15:41 +0300)]
perf intel-pt: Fix improved sample timestamp

commit 61b6e08dc8e3ea80b7485c9b3f875ddd45c8466b upstream.

The decoder uses its current timestamp in samples. Usually that is a
timestamp that has already passed, but in some cases it is a timestamp
for a branch that the decoder is walking towards, and consequently
hasn't reached.

The intel_pt_sample_time() function decides which is which, but was not
handling TNT packets exactly correctly.

In the case of TNT, the timestamp applies to the first branch, so the
decoder must first walk to that branch.

That means intel_pt_sample_time() should return true for TNT, and this
patch makes that change. However, if the first branch is a non-taken
branch (i.e. a 'N'), then intel_pt_sample_time() needs to return false
for subsequent taken branches in the same TNT packet.

To handle that, introduce a new state INTEL_PT_STATE_TNT_CONT to
distinguish the cases.

Note that commit 3f04d98e972b5 ("perf intel-pt: Improve sample
timestamp") was also a stable fix and appears, for example, in v4.4
stable tree as commit a4ebb58fd124 ("perf intel-pt: Improve sample
timestamp").

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: stable@vger.kernel.org # v4.4+
Fixes: 3f04d98e972b5 ("perf intel-pt: Improve sample timestamp")
Link: http://lkml.kernel.org/r/20190510124143.27054-3-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
5 years agoperf intel-pt: Fix instructions sampling rate
Adrian Hunter [Fri, 10 May 2019 12:41:41 +0000 (15:41 +0300)]
perf intel-pt: Fix instructions sampling rate

commit 7ba8fa20e26eb3c0c04d747f7fd2223694eac4d5 upstream.

The timestamp used to determine if an instruction sample is made, is an
estimate based on the number of instructions since the last known
timestamp. A consequence is that it might go backwards, which results in
extra samples. Change it so that a sample is only made when the
timestamp goes forwards.

Note this does not affect a sampling period of 0 or sampling periods
specified as a count of instructions.

Example:

 Before:

 $ perf script --itrace=i10us
 ls 13812 [003] 2167315.222583:       3270 instructions:u:      7fac71e2e494 __GI___tunables_init+0xf4 (/lib/x86_64-linux-gnu/ld-2.28.so)
 ls 13812 [003] 2167315.222667:      30902 instructions:u:      7fac71e2da0f _dl_cache_libcmp+0x2f (/lib/x86_64-linux-gnu/ld-2.28.so)
 ls 13812 [003] 2167315.222667:         10 instructions:u:      7fac71e2d9ff _dl_cache_libcmp+0x1f (/lib/x86_64-linux-gnu/ld-2.28.so)
 ls 13812 [003] 2167315.222667:          8 instructions:u:      7fac71e2d9ea _dl_cache_libcmp+0xa (/lib/x86_64-linux-gnu/ld-2.28.so)
 ls 13812 [003] 2167315.222667:         14 instructions:u:      7fac71e2d9ea _dl_cache_libcmp+0xa (/lib/x86_64-linux-gnu/ld-2.28.so)
 ls 13812 [003] 2167315.222667:          6 instructions:u:      7fac71e2d9ff _dl_cache_libcmp+0x1f (/lib/x86_64-linux-gnu/ld-2.28.so)
 ls 13812 [003] 2167315.222667:         14 instructions:u:      7fac71e2d9ff _dl_cache_libcmp+0x1f (/lib/x86_64-linux-gnu/ld-2.28.so)
 ls 13812 [003] 2167315.222667:          4 instructions:u:      7fac71e2dab2 _dl_cache_libcmp+0xd2 (/lib/x86_64-linux-gnu/ld-2.28.so)
 ls 13812 [003] 2167315.222728:      16423 instructions:u:      7fac71e2477a _dl_map_object_deps+0x1ba (/lib/x86_64-linux-gnu/ld-2.28.so)
 ls 13812 [003] 2167315.222734:      12731 instructions:u:      7fac71e27938 _dl_name_match_p+0x68 (/lib/x86_64-linux-gnu/ld-2.28.so)
 ...

 After:
 $ perf script --itrace=i10us
 ls 13812 [003] 2167315.222583:       3270 instructions:u:      7fac71e2e494 __GI___tunables_init+0xf4 (/lib/x86_64-linux-gnu/ld-2.28.so)
 ls 13812 [003] 2167315.222667:      30902 instructions:u:      7fac71e2da0f _dl_cache_libcmp+0x2f (/lib/x86_64-linux-gnu/ld-2.28.so)
 ls 13812 [003] 2167315.222728:      16479 instructions:u:      7fac71e2477a _dl_map_object_deps+0x1ba (/lib/x86_64-linux-gnu/ld-2.28.so)
 ...

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: stable@vger.kernel.org
Fixes: f4aa081949e7b ("perf tools: Add Intel PT decoder")
Link: http://lkml.kernel.org/r/20190510124143.27054-2-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
5 years agomemory: tegra: Fix integer overflow on tick value calculation
Dmitry Osipenko [Thu, 11 Apr 2019 22:12:48 +0000 (01:12 +0300)]
memory: tegra: Fix integer overflow on tick value calculation

commit b906c056b6023c390f18347169071193fda57dde upstream.

Multiplying the Memory Controller clock rate by the tick count results
in an integer overflow and in result the truncated tick value is being
programmed into hardware, such that the GR3D memory client performance is
reduced by two times.

Cc: stable <stable@vger.kernel.org>
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
5 years agotracing: Fix partial reading of trace event's id file
Elazar Leibovich [Mon, 31 Dec 2018 11:58:37 +0000 (13:58 +0200)]
tracing: Fix partial reading of trace event's id file

commit cbe08bcbbe787315c425dde284dcb715cfbf3f39 upstream.

When reading only part of the id file, the ppos isn't tracked correctly.
This is taken care by simple_read_from_buffer.

Reading a single byte, and then the next byte would result EOF.

While this seems like not a big deal, this breaks abstractions that
reads information from files unbuffered. See for example
https://github.com/golang/go/issues/29399

This code was mentioned as problematic in
commit cd458ba9d5a5
("tracing: Do not (ab)use trace_seq in event_id_read()")

An example C code that show this bug is:

  #include <stdio.h>
  #include <stdint.h>

  #include <sys/types.h>
  #include <sys/stat.h>
  #include <fcntl.h>
  #include <unistd.h>

  int main(int argc, char **argv) {
    if (argc < 2)
      return 1;
    int fd = open(argv[1], O_RDONLY);
    char c;
    read(fd, &c, 1);
    printf("First  %c\n", c);
    read(fd, &c, 1);
    printf("Second %c\n", c);
  }

Then run with, e.g.

  sudo ./a.out /sys/kernel/debug/tracing/events/tcp/tcp_set_state/id

You'll notice you're getting the first character twice, instead of the
first two characters in the id file.

Link: http://lkml.kernel.org/r/20181231115837.4932-1-elazar@lightbitslabs.com
Cc: Orit Wasserman <orit.was@gmail.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: stable@vger.kernel.org
Fixes: 23725aeeab10b ("ftrace: provide an id file for each event")
Signed-off-by: Elazar Leibovich <elazar@lightbitslabs.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
5 years agoftrace/x86_64: Emulate call function while updating in breakpoint handler
Peter Zijlstra [Wed, 1 May 2019 13:11:17 +0000 (15:11 +0200)]
ftrace/x86_64: Emulate call function while updating in breakpoint handler

commit 9e298e8604088a600d8100a111a532a9d342af09 upstream.

Nicolai Stange discovered[1] that if live kernel patching is enabled, and the
function tracer started tracing the same function that was patched, the
conversion of the fentry call site during the translation of going from
calling the live kernel patch trampoline to the iterator trampoline, would
have as slight window where it didn't call anything.

As live kernel patching depends on ftrace to always call its code (to
prevent the function being traced from being called, as it will redirect
it). This small window would allow the old buggy function to be called, and
this can cause undesirable results.

Nicolai submitted new patches[2] but these were controversial. As this is
similar to the static call emulation issues that came up a while ago[3].
But after some debate[4][5] adding a gap in the stack when entering the
breakpoint handler allows for pushing the return address onto the stack to
easily emulate a call.

[1] http://lkml.kernel.org/r/20180726104029.7736-1-nstange@suse.de
[2] http://lkml.kernel.org/r/20190427100639.15074-1-nstange@suse.de
[3] http://lkml.kernel.org/r/3cf04e113d71c9f8e4be95fb84a510f085aa4afa.1541711457.git.jpoimboe@redhat.com
[4] http://lkml.kernel.org/r/CAHk-=wh5OpheSU8Em_Q3Hg8qw_JtoijxOdPtHru6d+5K8TWM=A@mail.gmail.com
[5] http://lkml.kernel.org/r/CAHk-=wjvQxY4DvPrJ6haPgAa6b906h=MwZXO6G8OtiTGe=N7_w@mail.gmail.com

[
  Live kernel patching is not implemented on x86_32, thus the emulate
  calls are only for x86_64.
]

Cc: Andy Lutomirski <luto@kernel.org>
Cc: Nicolai Stange <nstange@suse.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: the arch/x86 maintainers <x86@kernel.org>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Jiri Kosina <jikos@kernel.org>
Cc: Miroslav Benes <mbenes@suse.cz>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Joe Lawrence <joe.lawrence@redhat.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Tim Chen <tim.c.chen@linux.intel.com>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Mimi Zohar <zohar@linux.ibm.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Nick Desaulniers <ndesaulniers@google.com>
Cc: Nayna Jain <nayna@linux.ibm.com>
Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Joerg Roedel <jroedel@suse.de>
Cc: "open list:KERNEL SELFTEST FRAMEWORK" <linux-kselftest@vger.kernel.org>
Cc: stable@vger.kernel.org
Fixes: b700e7f03df5 ("livepatch: kernel: add support for live patching")
Tested-by: Nicolai Stange <nstange@suse.de>
Reviewed-by: Nicolai Stange <nstange@suse.de>
Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
[ Changed to only implement emulated calls for x86_64 ]
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
5 years agox86_64: Allow breakpoints to emulate call instructions
Peter Zijlstra [Wed, 1 May 2019 13:11:17 +0000 (15:11 +0200)]
x86_64: Allow breakpoints to emulate call instructions

commit 4b33dadf37666c0860b88f9e52a16d07bf6d0b03 upstream.

In order to allow breakpoints to emulate call instructions, they need to push
the return address onto the stack. The x86_64 int3 handler adds a small gap
to allow the stack to grow some. Use this gap to add the return address to
be able to emulate a call instruction at the breakpoint location.

These helper functions are added:

  int3_emulate_jmp(): changes the location of the regs->ip to return there.

 (The next two are only for x86_64)
  int3_emulate_push(): to push the address onto the gap in the stack
  int3_emulate_call(): push the return address and change regs->ip

Cc: Andy Lutomirski <luto@kernel.org>
Cc: Nicolai Stange <nstange@suse.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: the arch/x86 maintainers <x86@kernel.org>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Jiri Kosina <jikos@kernel.org>
Cc: Miroslav Benes <mbenes@suse.cz>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Joe Lawrence <joe.lawrence@redhat.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Tim Chen <tim.c.chen@linux.intel.com>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Mimi Zohar <zohar@linux.ibm.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Nick Desaulniers <ndesaulniers@google.com>
Cc: Nayna Jain <nayna@linux.ibm.com>
Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Joerg Roedel <jroedel@suse.de>
Cc: "open list:KERNEL SELFTEST FRAMEWORK" <linux-kselftest@vger.kernel.org>
Cc: stable@vger.kernel.org
Fixes: b700e7f03df5 ("livepatch: kernel: add support for live patching")
Tested-by: Nicolai Stange <nstange@suse.de>
Reviewed-by: Nicolai Stange <nstange@suse.de>
Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
[ Modified to only work for x86_64 and added comment to int3_emulate_push() ]
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
5 years agox86_64: Add gap to int3 to allow for call emulation
Josh Poimboeuf [Fri, 30 Nov 2018 18:39:17 +0000 (12:39 -0600)]
x86_64: Add gap to int3 to allow for call emulation

commit 2700fefdb2d9751c416ad56897e27d41e409324a upstream.

To allow an int3 handler to emulate a call instruction, it must be able to
push a return address onto the stack. Add a gap to the stack to allow the
int3 handler to push the return address and change the return from int3 to
jump straight to the emulated called function target.

Link: http://lkml.kernel.org/r/20181130183917.hxmti5josgq4clti@treble
Link: http://lkml.kernel.org/r/20190502162133.GX2623@hirez.programming.kicks-ass.net
[
  Note, this is needed to allow Live Kernel Patching to not miss calling a
  patched function when tracing is enabled. -- Steven Rostedt
]

Cc: stable@vger.kernel.org
Fixes: b700e7f03df5 ("livepatch: kernel: add support for live patching")
Tested-by: Nicolai Stange <nstange@suse.de>
Reviewed-by: Nicolai Stange <nstange@suse.de>
Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
5 years agoceph: flush dirty inodes before proceeding with remount
Jeff Layton [Tue, 7 May 2019 13:20:54 +0000 (09:20 -0400)]
ceph: flush dirty inodes before proceeding with remount

commit 00abf69dd24f4444d185982379c5cc3bb7b6d1fc upstream.

xfstest generic/452 was triggering a "Busy inodes after umount" warning.
ceph was allowing the mount to go read-only without first flushing out
dirty inodes in the cache. Ensure we sync out the filesystem before
allowing a remount to proceed.

Cc: stable@vger.kernel.org
Link: http://tracker.ceph.com/issues/39571
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: "Yan, Zheng" <zyan@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>