Re: [syzbot] WARNING in io_rsrc_node_switch

[Pavel Begunkov <asml.silence@gmail.com>]

On 4/29/21 11:32 AM, syzbot wrote:
> syzbot has found a reproducer for the following issue on:
> 
> HEAD commit:    d72cd4ad Merge tag 'scsi-misc' of git://git.kernel.org/pub..
> git tree:       upstream
> console output: https://syzkaller.appspot.com/x/log.txt?x=12c045d5d00000
> kernel config:  https://syzkaller.appspot.com/x/.config?x=65c207250bba4efe
> dashboard link: https://syzkaller.appspot.com/bug?extid=a4715dd4b7c866136f79
> syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=11893de1d00000
> C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=161c19d5d00000

#syz test: https://github.com/isilence/linux.git syz_test4

> 
> IMPORTANT: if you fix the issue, please add the following tag to the commit:
> Reported-by: syzbot+a4715dd4b7c866136f79@syzkaller.appspotmail.com
> 
> RAX: ffffffffffffffda RBX: 0000000000000001 RCX: 0000000000440a49
> RDX: 0000000000000010 RSI: 00000000200002c0 RDI: 0000000000000182
> RBP: 00007fff0b88f050 R08: 0000000000000001 R09: 00007fff0b88f038
> R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000003
> R13: 00007fff0b88f03a R14: 00000000004b74b0 R15: 000000000000000c
> ------------[ cut here ]------------
> WARNING: CPU: 0 PID: 8397 at fs/io_uring.c:7081 io_rsrc_node_switch+0x2a5/0x390 fs/io_uring.c:7081
> Modules linked in:
> CPU: 0 PID: 8397 Comm: syz-executor469 Not tainted 5.12.0-syzkaller #0
> Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
> RIP: 0010:io_rsrc_node_switch+0x2a5/0x390 fs/io_uring.c:7081
> Code: ff 4d 85 e4 74 a4 48 83 c4 20 5b 5d 41 5c 41 5d 41 5e 41 5f e9 fc 00 99 ff e8 f7 00 99 ff 0f 0b e9 ee fd ff ff e8 eb 00 99 ff <0f> 0b e9 9d fd ff ff 4c 89 f7 e8 7c e0 dc ff eb 8b 4c 89 ef e8 72
> RSP: 0018:ffffc9000164fd90 EFLAGS: 00010293
> RAX: 0000000000000000 RBX: ffff8880196fe000 RCX: 0000000000000000
> RDX: ffff88801c7a1c40 RSI: ffffffff81db5d25 RDI: ffff8880196fe000
> RBP: 0000000000000000 R08: 0000000000000dc0 R09: ffffffff8c0b37d3
> R10: fffffbfff18166fa R11: 0000000000000000 R12: 0000000000000000
> R13: 0000000000000000 R14: ffff8880196fe808 R15: 0000000000000000
> FS:  0000000001485300(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000
> CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
> CR2: 00000000200002c4 CR3: 00000000160b2000 CR4: 0000000000350ef0
> Call Trace:
>  io_uring_create fs/io_uring.c:9611 [inline]
>  io_uring_setup+0xf75/0x2a80 fs/io_uring.c:9689
>  do_syscall_64+0x3a/0xb0 arch/x86/entry/common.c:47
>  entry_SYSCALL_64_after_hwframe+0x44/0xae
> RIP: 0033:0x440a49
> Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 41 15 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:00007fff0b88f008 EFLAGS: 00000246 ORIG_RAX: 00000000000001a9
> RAX: ffffffffffffffda RBX: 0000000000000001 RCX: 0000000000440a49
> RDX: 0000000000000010 RSI: 00000000200002c0 RDI: 0000000000000182
> RBP: 00007fff0b88f050 R08: 0000000000000001 R09: 00007fff0b88f038
> R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000003
> R13: 00007fff0b88f03a R14: 00000000004b74b0 R15: 000000000000000c
> 

-- 
Pavel Begunkov