general protection fault in __vfs_write (2)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: cbfa1702 Linux 4.14.198
git tree: linux-4.14.y
console output: https://syzkaller.appspot.com/x/log.txt?x=130bfdd7900000
kernel config: https://syzkaller.appspot.com/x/.config?x=3990958d85b55e59
dashboard link: https://syzkaller.appspot.com/bug?extid=4caad7ea5e910fb6d9ff
compiler: gcc (GCC) 10.1.0-syz 20200507

Unfortunately, I don't have any reproducer for this issue yet.

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+4caad7...@syzkaller.appspotmail.com

SYSC_add_key security/keys/keyctl.c:123 [inline]
SyS_add_key+0x186/0x370 security/keys/keyctl.c:63
kasan: GPF could be caused by NULL-ptr deref or user memory access
do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292
general protection fault: 0000 [#1] PREEMPT SMP KASAN
entry_SYSCALL_64_after_hwframe+0x46/0xbb
Modules linked in:
RIP: 0033:0x45de59
RSP: 002b:00007f3d2d477c78 EFLAGS: 00000246
CPU: 0 PID: 10327 Comm: syz-executor.2 Not tainted 4.14.198-syzkaller #0
ORIG_RAX: 00000000000000f8
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RAX: ffffffffffffffda RBX: 0000000000000740 RCX: 000000000045de59
task: ffff8880a9660140 task.stack: ffff8880687b8000
RDX: 00000000200000c0 RSI: 0000000020000080 RDI: 0000000020000000
RIP: 0010:vhost_umem_interval_tree_iter_first drivers/vhost/vhost.c:53 [inline]
RIP: 0010:vhost_del_umem_range drivers/vhost/vhost.c:971 [inline]
RIP: 0010:vhost_process_iotlb_msg drivers/vhost/vhost.c:1042 [inline]
RIP: 0010:vhost_chr_write_iter drivers/vhost/vhost.c:1071 [inline]
RIP: 0010:vhost_chr_write_iter+0x863/0x10f0 drivers/vhost/vhost.c:1055
RBP: 00007f3d2d477ca0 R08: fffffffffffffffc R09: 0000000000000000
RSP: 0018:ffff8880687bfc00 EFLAGS: 00010246
R10: 0000000000000001 R11: 0000000000000246 R12: 0000000000000005
R13: 00007ffde044623f R14: 00007f3d2d4789c0 R15: 000000000118bf2c
RAX: dffffc0000000000 RBX: ffff88804f745980 RCX: 0000000000000000
RDX: 0000000000000002 RSI: ffffffff84e39155 RDI: ffff88804f745a40
RBP: ffffed1009ee8b41 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000002 R11: ffff8880a9660140 R12: 0000000000000002
R13: 0000000000000000 R14: dffffc0000000000 R15: 1ffff1100d0f7f87
FS: 00007f324dc2d700(0000) GS:ffff8880aea00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f1b1cf93010 CR3: 0000000082c79000 CR4: 00000000001406f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
call_write_iter include/linux/fs.h:1778 [inline]
new_sync_write fs/read_write.c:469 [inline]
__vfs_write+0x44c/0x630 fs/read_write.c:482
vfs_write+0x17f/0x4d0 fs/read_write.c:544
SYSC_write fs/read_write.c:590 [inline]
SyS_write+0xf2/0x210 fs/read_write.c:582
do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292
FAULT_INJECTION: forcing a failure.
name failslab, interval 1, probability 0, space 0, times 0
entry_SYSCALL_64_after_hwframe+0x46/0xbb
RIP: 0033:0x45de59
RSP: 002b:00007f324dc2cc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 000000000003b880 RCX: 000000000045de59
RDX: 0000000000000048 RSI: 0000000020000140 RDI: 0000000000000003
RBP: 000000000118bf60 R08: 0000000000000000 R09: 0000000000000000
CPU: 1 PID: 10343 Comm: syz-executor.3 Not tainted 4.14.198-syzkaller #0
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000118bf2c
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
R13: 00007fffaced5faf R14: 00007f324dc2d9c0 R15: 000000000118bf2c
Call Trace:
Code:
__dump_stack lib/dump_stack.c:17 [inline]
dump_stack+0x1b2/0x283 lib/dump_stack.c:58
ff
fail_dump lib/fault-inject.c:51 [inline]
should_fail.cold+0x10a/0x154 lib/fault-inject.c:149
df
should_failslab+0xd6/0x130 mm/failslab.c:32
48
slab_pre_alloc_hook mm/slab.h:421 [inline]
slab_alloc mm/slab.c:3376 [inline]
kmem_cache_alloc_trace+0x29a/0x3d0 mm/slab.c:3616
89
kmalloc include/linux/slab.h:488 [inline]
kzalloc include/linux/slab.h:661 [inline]
selinux_key_alloc+0x46/0x1a0 security/selinux/hooks.c:6184
f9
security_key_alloc+0x76/0xb0 security/security.c:1669
48
c1
key_alloc+0x6bf/0xf80 security/keys/key.c:314
e9
03
key_create_or_update+0x59f/0xaa0 security/keys/key.c:916
80
3c
01
SYSC_add_key security/keys/keyctl.c:123 [inline]
SyS_add_key+0x186/0x370 security/keys/keyctl.c:63
00
0f
85
cd
06
do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292
00
entry_SYSCALL_64_after_hwframe+0x46/0xbb
00
RIP: 0033:0x45de59
4c
RSP: 002b:00007f3d2d477c78 EFLAGS: 00000246
8b
ORIG_RAX: 00000000000000f8
ab
RAX: ffffffffffffffda RBX: 0000000000000740 RCX: 000000000045de59
c0
RDX: 00000000200000c0 RSI: 0000000020000080 RDI: 0000000020000000
00
RBP: 00007f3d2d477ca0 R08: fffffffffffffffc R09: 0000000000000000
00
R10: 0000000000000001 R11: 0000000000000246 R12: 0000000000000006
00
R13: 00007ffde044623f R14: 00007f3d2d4789c0 R15: 000000000118bf2c
48 b8 00 00 00 00 00 fc ff df 4c 89 e9 48 c1 e9 03 <80> 3c 01 00 0f 85 96 06 00 00 49 8b 6d 00 48 85 ed 0f 84 e4 03
RIP: vhost_umem_interval_tree_iter_first drivers/vhost/vhost.c:53 [inline] RSP: ffff8880687bfc00
RIP: vhost_del_umem_range drivers/vhost/vhost.c:971 [inline] RSP: ffff8880687bfc00
RIP: vhost_process_iotlb_msg drivers/vhost/vhost.c:1042 [inline] RSP: ffff8880687bfc00
RIP: vhost_chr_write_iter drivers/vhost/vhost.c:1071 [inline] RSP: ffff8880687bfc00
RIP: vhost_chr_write_iter+0x863/0x10f0 drivers/vhost/vhost.c:1055 RSP: ffff8880687bfc00
---[ end trace 434ecda860b773cd ]---


---
This report is generated by a bot. It may contain errors.
See https://goo.gl/tpsmEJ for more information about syzbot.
syzbot engineers can be reached at syzk...@googlegroups.com.

syzbot will keep track of this issue. See:
https://goo.gl/tpsmEJ#status for how to communicate with syzbot.

[syzbot]

Auto-closing this bug as obsolete.
Crashes did not happen for a while, no reproducer and no activity.