iommufd/selftest: Catch overflow of uptr and length
syzkaller hits a WARN_ON when trying to have a uptr close to UINTPTR_MAX:
WARNING: CPU: 1 PID: 393 at drivers/iommu/iommufd/selftest.c:403 iommufd_test+0xb19/0x16f0
Modules linked in:
CPU: 1 PID: 393 Comm: repro Not tainted 6.2.0-
c9c3395d5e3d #1
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.0-0-gd239552ce722-prebuilt.qemu.org 04/01/2014
RIP: 0010:iommufd_test+0xb19/0x16f0
Code: 94 c4 31 ff 44 89 e6 e8 a5 54 17 ff 45 84 e4 0f 85 bb 0b 00 00 41 be fb ff ff ff e8 31 53 17 ff e9 a0 f7 ff ff e8 27 53 17 ff <0f> 0b 41 be 8
RSP: 0018:
ffffc90000eabdc0 EFLAGS:
00010246
RAX:
0000000000000000 RBX:
0000000000000000 RCX:
ffffffff8214c487
RDX:
0000000000000000 RSI:
ffff88800f5c8000 RDI:
0000000000000002
RBP:
ffffc90000eabe48 R08:
0000000000000000 R09:
0000000000000001
R10:
0000000000000001 R11:
0000000000000000 R12:
00000000cd2b0000
R13:
00000000cd2af000 R14:
0000000000000000 R15:
ffffc90000eabe68
FS:
00007f94d76d5740(0000) GS:
ffff88807dd00000(0000) knlGS:
0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0:
0000000080050033
CR2:
0000000020000043 CR3:
0000000006880006 CR4:
0000000000770ee0
PKRU:
55555554
Call Trace:
<TASK>
? write_comp_data+0x2f/0x90
iommufd_fops_ioctl+0x1ef/0x310
__x64_sys_ioctl+0x10e/0x160
? __pfx_iommufd_fops_ioctl+0x10/0x10
do_syscall_64+0x3b/0x90
entry_SYSCALL_64_after_hwframe+0x72/0xdc
Check that the user memory range doesn't overflow.
Fixes:
f4b20bb34c83 ("iommufd: Add kernel support for testing iommufd")
Link: https://lore.kernel.org/r/0-v1-95390ed1df8d+8f-iommufd_mock_overflow_jgg@nvidia.com
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reported-by: Pengfei Xu <pengfei.xu@intel.com>
Link: https://lore.kernel.org/r/Y/hOiilV1wJvu/Hv@xpf.sh.intel.com
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>