syzbot


general protection fault in io_kill_timeouts
Status: upstream: reported C repro on 2022/03/23 17:52
Reported-by: syzbot+f252f28df734e8521387@syzkaller.appspotmail.com
First crash: 65d, last: 64d

Cause bisection: introduced by (bisect log) :
commit c9be622494c012d56c71e00cb90be841820c3e34
Author: Pavel Begunkov <asml.silence@gmail.com>
Date: Mon Mar 21 22:02:20 2022 +0000

  io_uring: remove extra ifs around io_commit_cqring

Crash: general protection fault in io_kill_timeouts (log)
Repro: C syz .config
Patch testing requests:
Created Duration User Patch Repo Result
2022/03/23 19:36 11m asml.silence@gmail.com git://git.kernel.dk/linux-block for-5.18/io_uring OK

Sample crash report:
RDX: 0000000000000f90 RSI: 00000000200000c0 RDI: 00000000000078af
RBP: 00007fffd1ad3f90 R08: 0000000000000001 R09: 0000000000000001
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000003
R13: 431bde82d7b634db R14: 0000000000000000 R15: 0000000000000000
 </TASK>
general protection fault, probably for non-canonical address 0xdffffc0000000018: 0000 [#1] PREEMPT SMP KASAN
KASAN: null-ptr-deref in range [0x00000000000000c0-0x00000000000000c7]
CPU: 0 PID: 3589 Comm: syz-executor273 Tainted: G        W         5.17.0-next-20220323-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:io_commit_cqring fs/io_uring.c:1812 [inline]
RIP: 0010:io_kill_timeouts+0x267/0x2ce fs/io_uring.c:10297
Code: 74 09 3c 03 7f 05 e8 c5 ca a7 f8 49 8d bc 24 c0 00 00 00 b8 ff ff 37 00 44 8b ad 40 03 00 00 48 89 fa 48 c1 e0 2a 48 c1 ea 03 <8a> 14 02 48 89 f8 83 e0 07 83 c0 03 38 d0 7c 09 84 d2 74 05 e8 fd
RSP: 0018:ffffc9000399fcf8 EFLAGS: 00010206
RAX: dffffc0000000000 RBX: 0000000000000000 RCX: 0000000000000000
RDX: 0000000000000018 RSI: ffffffff817ef121 RDI: 00000000000000c0
RBP: ffff888011a75000 R08: 0000000000000000 R09: 0000000000000000
R10: ffffffff817ef108 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: ffff888011a75040 R15: 0000000000000001
FS:  0000555557264300(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055a52ec10058 CR3: 0000000024024000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 io_ring_ctx_wait_and_kill+0x1c2/0x327 fs/io_uring.c:10317
 io_uring_create fs/io_uring.c:11385 [inline]
 io_uring_setup.cold+0x10a3/0x263b fs/io_uring.c:11412
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x35/0x80 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7f85ced00069
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 b1 14 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 c0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fffd1ad3f78 EFLAGS: 00000246 ORIG_RAX: 00000000000001a9
RAX: ffffffffffffffda RBX: 0000000000000001 RCX: 00007f85ced00069
RDX: 0000000000000f90 RSI: 00000000200000c0 RDI: 00000000000078af
RBP: 00007fffd1ad3f90 R08: 0000000000000001 R09: 0000000000000001
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000003
R13: 431bde82d7b634db R14: 0000000000000000 R15: 0000000000000000
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:io_commit_cqring fs/io_uring.c:1812 [inline]
RIP: 0010:io_kill_timeouts+0x267/0x2ce fs/io_uring.c:10297
Code: 74 09 3c 03 7f 05 e8 c5 ca a7 f8 49 8d bc 24 c0 00 00 00 b8 ff ff 37 00 44 8b ad 40 03 00 00 48 89 fa 48 c1 e0 2a 48 c1 ea 03 <8a> 14 02 48 89 f8 83 e0 07 83 c0 03 38 d0 7c 09 84 d2 74 05 e8 fd
RSP: 0018:ffffc9000399fcf8 EFLAGS: 00010206
RAX: dffffc0000000000 RBX: 0000000000000000 RCX: 0000000000000000
RDX: 0000000000000018 RSI: ffffffff817ef121 RDI: 00000000000000c0
RBP: ffff888011a75000 R08: 0000000000000000 R09: 0000000000000000
R10: ffffffff817ef108 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: ffff888011a75040 R15: 0000000000000001
FS:  0000555557264300(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055a52ec10058 CR3: 0000000024024000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess):
   0:	74 09                	je     0xb
   2:	3c 03                	cmp    $0x3,%al
   4:	7f 05                	jg     0xb
   6:	e8 c5 ca a7 f8       	callq  0xf8a7cad0
   b:	49 8d bc 24 c0 00 00 	lea    0xc0(%r12),%rdi
  12:	00
  13:	b8 ff ff 37 00       	mov    $0x37ffff,%eax
  18:	44 8b ad 40 03 00 00 	mov    0x340(%rbp),%r13d
  1f:	48 89 fa             	mov    %rdi,%rdx
  22:	48 c1 e0 2a          	shl    $0x2a,%rax
  26:	48 c1 ea 03          	shr    $0x3,%rdx
* 2a:	8a 14 02             	mov    (%rdx,%rax,1),%dl <-- trapping instruction
  2d:	48 89 f8             	mov    %rdi,%rax
  30:	83 e0 07             	and    $0x7,%eax
  33:	83 c0 03             	add    $0x3,%eax
  36:	38 d0                	cmp    %dl,%al
  38:	7c 09                	jl     0x43
  3a:	84 d2                	test   %dl,%dl
  3c:	74 05                	je     0x43
  3e:	e8                   	.byte 0xe8
  3f:	fd                   	std

Crashes (14):
Manager Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Title
ci-upstream-linux-next-kasan-gce-root 2022/03/23 14:26 linux-next b61581ae229d 5ff41e94 .config log report syz C general protection fault in io_kill_timeouts
ci-upstream-linux-next-kasan-gce-root 2022/03/24 08:18 linux-next b61581ae229d 5ff41e94 .config log report info general protection fault in io_kill_timeouts
ci-upstream-linux-next-kasan-gce-root 2022/03/24 06:04 linux-next b61581ae229d 5ff41e94 .config log report info general protection fault in io_kill_timeouts
ci-upstream-linux-next-kasan-gce-root 2022/03/24 05:25 linux-next b61581ae229d 5ff41e94 .config log report info general protection fault in io_kill_timeouts
ci-upstream-linux-next-kasan-gce-root 2022/03/24 04:19 linux-next b61581ae229d 5ff41e94 .config log report info general protection fault in io_kill_timeouts
ci-upstream-linux-next-kasan-gce-root 2022/03/24 03:46 linux-next b61581ae229d 5ff41e94 .config log report info general protection fault in io_kill_timeouts
ci-upstream-linux-next-kasan-gce-root 2022/03/24 03:33 linux-next b61581ae229d 5ff41e94 .config log report info general protection fault in io_kill_timeouts
ci-upstream-linux-next-kasan-gce-root 2022/03/24 03:21 linux-next b61581ae229d 5ff41e94 .config log report info general protection fault in io_kill_timeouts
ci-upstream-linux-next-kasan-gce-root 2022/03/24 00:17 linux-next b61581ae229d 5ff41e94 .config log report info general protection fault in io_kill_timeouts
ci-upstream-linux-next-kasan-gce-root 2022/03/23 23:58 linux-next b61581ae229d 5ff41e94 .config log report info general protection fault in io_kill_timeouts
ci-upstream-linux-next-kasan-gce-root 2022/03/23 21:24 linux-next b61581ae229d 5ff41e94 .config log report info general protection fault in io_kill_timeouts
ci-upstream-linux-next-kasan-gce-root 2022/03/23 19:38 linux-next b61581ae229d 5ff41e94 .config log report info general protection fault in io_kill_timeouts
ci-upstream-linux-next-kasan-gce-root 2022/03/23 19:29 linux-next b61581ae229d 5ff41e94 .config log report info general protection fault in io_kill_timeouts
ci-upstream-linux-next-kasan-gce-root 2022/03/23 14:16 linux-next b61581ae229d 5ff41e94 .config log report info general protection fault in io_kill_timeouts