syzbot


WARNING in io_try_cancel_userdata

Status: fixed on 2021/11/10 00:50
Subsystems: fs io-uring
[Documentation on labels]
Reported-by: syzbot+b0c9d1588ae92866515f@syzkaller.appspotmail.com
Fix commit: dadebc350da2 io_uring: fix io_try_cancel_userdata race for iowq
First crash: 1062d, last: 1056d
Cause bisection: introduced by (bisect log) [no-op commit]:
commit b9fc8b4a591811546fec2dbef7e9f809362100c9
Author: Grant Seltzer <grantseltzer@gmail.com>
Date: Mon Feb 22 19:58:46 2021 +0000

  bpf: Add kernel/modules BTF presence checks to bpftool feature command

Crash: WARNING in kvm_wait (log)
Repro: syz .config
  
Discussions (4)
Title Replies (including bot) Last reply
[PATCH 5.13 000/380] 5.13.19-rc1 review 391 (391) 2021/10/01 17:10
[PATCH 5.14 000/432] 5.14.6-rc1 review 439 (439) 2021/09/17 17:59
[syzbot] WARNING in io_try_cancel_userdata 2 (4) 2021/08/23 22:14
[PATCH] io_uring: fix io_try_cancel_userdata race for iowq 2 (2) 2021/08/23 16:17
Similar bugs (1)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream WARNING in io_try_cancel_userdata (2) fs 1 969d 965d 20/27 fixed on 2022/03/08 16:11

Sample crash report:
------------[ cut here ]------------
WARNING: CPU: 0 PID: 7008 at fs/io_uring.c:6082 io_try_cancel_userdata+0x30d/0x540 fs/io_uring.c:6082
Modules linked in:
CPU: 0 PID: 7008 Comm: iou-wrk-7007 Not tainted 5.14.0-rc7-next-20210823-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:io_try_cancel_userdata+0x30d/0x540 fs/io_uring.c:6082
Code: 52 07 e8 66 67 95 ff 48 8b 3c 24 e8 ad 67 52 07 e9 71 fe ff ff e8 53 67 95 ff 41 bf 8e ff ff ff e9 61 fe ff ff e8 43 67 95 ff <0f> 0b 48 b8 00 00 00 00 00 fc ff df 4c 89 fa 48 c1 ea 03 80 3c 02
RSP: 0018:ffffc90003fefac0 EFLAGS: 00010293
RAX: 0000000000000000 RBX: ffff88801d064c80 RCX: 0000000000000000
RDX: ffff88801ea75580 RSI: ffffffff81e078fd RDI: ffff88801d064cd0
RBP: ffff88801ea75580 R08: ffffffff899adde0 R09: ffffffff81e1e4e4
R10: 0000000000000027 R11: 000000000000000e R12: 1ffff920007fdf59
R13: 0000000000012345 R14: ffff888146628000 R15: ffff88801d064ce0
FS:  00007f0c5b7d6700(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffc3bfd8720 CR3: 0000000070d9c000 CR4: 00000000001506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 io_async_cancel fs/io_uring.c:6122 [inline]
 io_issue_sqe+0x22d5/0x67b0 fs/io_uring.c:6515
 io_wq_submit_work+0x1d4/0x300 fs/io_uring.c:6619
 io_worker_handle_work+0x1584/0x1810 fs/io-wq.c:533
 io_wqe_worker+0x9cd/0xbb0 fs/io-wq.c:606
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295

Crashes (4):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2021/08/23 22:13 linux-next 46debfec12b4 b599f2fc .config console log report syz ci-upstream-linux-next-kasan-gce-root WARNING in io_try_cancel_userdata
2021/08/27 11:12 linux-next 88fac11862d3 b318694d .config console log report info ci-upstream-linux-next-kasan-gce-root WARNING in io_try_cancel_userdata
2021/08/23 21:52 linux-next 46debfec12b4 b599f2fc .config console log report info ci-upstream-linux-next-kasan-gce-root WARNING in io_try_cancel_userdata
2021/08/21 03:53 linux-next 86ed57fd8c93 b599f2fc .config console log report info ci-upstream-linux-next-kasan-gce-root WARNING in io_try_cancel_userdata
* Struck through repros no longer work on HEAD.