Re: WARNING in io_disable_sqo_submit

[Pavel Begunkov]

On 18/01/2021 04:27, syzbot wrote:
> syzbot has found a reproducer for the following issue on:
> 
> HEAD commit:    a1339d63 Merge tag 'powerpc-5.11-4' of git://git.kernel.or..
> git tree:       upstream
> console output: https://syzkaller.appspot.com/x/log.txt?x=17532a58d00000
> kernel config:  https://syzkaller.appspot.com/x/.config?x=c60c9ff9cc916cbc
> dashboard link: https://syzkaller.appspot.com/bug?extid=2f5d1785dc624932da78
> compiler:       gcc (GCC) 10.1.0-syz 20200507
> syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=10f207c7500000
> 

#syz test: git://git.kernel.dk/linux-block io_uring-5.11

> IMPORTANT: if you fix the issue, please add the following tag to the commit:
> Reported-by: syzbot+2f5d1785dc624932da78@xxxxxxxxxxxxxxxxxxxxxxxxx
> 
> ------------[ cut here ]------------
> WARNING: CPU: 0 PID: 9113 at fs/io_uring.c:8917 io_disable_sqo_submit+0x13d/0x180 fs/io_uring.c:8917
> Modules linked in:
> CPU: 1 PID: 9113 Comm: syz-executor.0 Not tainted 5.11.0-rc3-syzkaller #0
> Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
> RIP: 0010:io_disable_sqo_submit+0x13d/0x180 fs/io_uring.c:8917
> Code: e0 07 83 c0 03 38 d0 7c 04 84 d2 75 2e 83 8b 14 01 00 00 01 4c 89 e7 e8 31 0a 24 07 5b 5d 41 5c e9 98 e1 9a ff e8 93 e1 9a ff <0f> 0b e9 00 ff ff ff e8 a7 a1 dd ff e9 37 ff ff ff e8 6d a1 dd ff
> RSP: 0018:ffffc9000311fe98 EFLAGS: 00010293
> RAX: 0000000000000000 RBX: ffff888024b43000 RCX: 0000000000000000
> RDX: ffff888147071bc0 RSI: ffffffff81d7e82d RDI: ffff888024b430d0
> RBP: ffff8880115d1900 R08: 0000000000000000 R09: 0000000014555c01
> R10: ffffffff81d7eae5 R11: 0000000000000001 R12: ffff888024b43000
> R13: ffff888014555c01 R14: ffff888024b43040 R15: ffff888024b430d0
> FS:  00007f85abf55700(0000) GS:ffff8880b9e00000(0000) knlGS:0000000000000000
> CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
> CR2: 00007fd3adeb5000 CR3: 00000000115d2000 CR4: 0000000000350ef0
> Call Trace:
>  io_uring_flush+0x28b/0x3a0 fs/io_uring.c:9134
>  filp_close+0xb4/0x170 fs/open.c:1280
>  close_fd+0x5c/0x80 fs/file.c:626
>  __do_sys_close fs/open.c:1299 [inline]
>  __se_sys_close fs/open.c:1297 [inline]
>  __x64_sys_close+0x2f/0xa0 fs/open.c:1297
>  do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
>  entry_SYSCALL_64_after_hwframe+0x44/0xa9
> RIP: 0033:0x45e219
> Code: 0d b4 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 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 0f 83 db b3 fb ff c3 66 2e 0f 1f 84 00 00 00 00
> RSP: 002b:00007f85abf54c68 EFLAGS: 00000246 ORIG_RAX: 0000000000000003
> RAX: ffffffffffffffda RBX: 0000000000000001 RCX: 000000000045e219
> RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000004
> RBP: 000000000119bfb0 R08: 0000000000000000 R09: 0000000000000000
> R10: 0000000000000000 R11: 0000000000000246 R12: 000000000119bf8c
> R13: 00007ffe5217973f R14: 00007f85abf559c0 R15: 000000000119bf8c
> 

-- 
Pavel Begunkov