xhci: Fix kernel oops in trace_xhci_free_virt_device
authorZhengjun Xing <zhengjun.xing@linux.intel.com>
Thu, 21 Jun 2018 13:19:42 +0000 (16:19 +0300)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Sun, 8 Jul 2018 13:30:47 +0000 (15:30 +0200)
commit716382f1c1eaca706ab694a61215b5e3416a0ea6
treed5323dd503be2faf34f53411fcff0ba1a0e388e0
parent0a7db82ed9ccbf6a85f4269a454e06e438b41b99
xhci: Fix kernel oops in trace_xhci_free_virt_device

commit d850c1658328e757635a46763783c6fd56390dcb upstream.

commit 44a182b9d177 ("xhci: Fix use-after-free in xhci_free_virt_device")
set dev->udev pointer to NULL in xhci_free_dev(), it will cause kernel
panic in trace_xhci_free_virt_device. This patch reimplement the trace
function trace_xhci_free_virt_device, remove dev->udev dereference and
added more useful parameters to show in the trace function,it also makes
sure dev->udev is not NULL before calling trace_xhci_free_virt_device.
This issue happened when xhci-hcd trace is enabled and USB devices hot
plug test. Original use-after-free patch went to stable so this needs so
be applied there as well.

[ 1092.022457] usb 2-4: USB disconnect, device number 6
[ 1092.092772] BUG: unable to handle kernel NULL pointer dereference at 0000000000000000
[ 1092.101694] PGD 0 P4D 0
[ 1092.104601] Oops: 0000 [#1] SMP
[ 1092.207734] Workqueue: usb_hub_wq hub_event
[ 1092.212507] RIP: 0010:trace_event_raw_event_xhci_log_virt_dev+0x6c/0xf0
[ 1092.220050] RSP: 0018:ffff8c252e883d28 EFLAGS: 00010086
[ 1092.226024] RAX: ffff8c24af86fa84 RBX: 0000000000000003 RCX: ffff8c25255c2a01
[ 1092.234130] RDX: 0000000000000000 RSI: 00000000aef55009 RDI: ffff8c252e883d28
[ 1092.242242] RBP: ffff8c252550e2c0 R08: ffff8c24af86fa84 R09: 0000000000000a70
[ 1092.250364] R10: 0000000000000a70 R11: 0000000000000000 R12: ffff8c251f21a000
[ 1092.258468] R13: 000000000000000c R14: ffff8c251f21a000 R15: ffff8c251f432f60
[ 1092.266572] FS:  0000000000000000(0000) GS:ffff8c252e880000(0000) knlGS:0000000000000000
[ 1092.275757] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 1092.282281] CR2: 0000000000000000 CR3: 0000000154209001 CR4: 00000000003606e0
[ 1092.290384] Call Trace:
[ 1092.293156]  <IRQ>
[ 1092.295439]  xhci_free_virt_device.part.34+0x182/0x1a0
[ 1092.301288]  handle_cmd_completion+0x7ac/0xfa0
[ 1092.306336]  ? trace_event_raw_event_xhci_log_trb+0x6e/0xa0
[ 1092.312661]  xhci_irq+0x3e8/0x1f60
[ 1092.316524]  __handle_irq_event_percpu+0x75/0x180
[ 1092.321876]  handle_irq_event_percpu+0x20/0x50
[ 1092.326922]  handle_irq_event+0x36/0x60
[ 1092.331273]  handle_edge_irq+0x6d/0x180
[ 1092.335644]  handle_irq+0x16/0x20
[ 1092.339417]  do_IRQ+0x41/0xc0
[ 1092.342782]  common_interrupt+0xf/0xf
[ 1092.346955]  </IRQ>

Fixes: 44a182b9d177 ("xhci: Fix use-after-free in xhci_free_virt_device")
Cc: <stable@vger.kernel.org>
Signed-off-by: Zhengjun Xing <zhengjun.xing@linux.intel.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drivers/usb/host/xhci-mem.c
drivers/usb/host/xhci-trace.h