Re: [syzbot] WARNING in blk_mq_release

syzbot
2022-08-09T10:41:36Z

syzbot has found a reproducer for the following issue on:

HEAD commit: 200e340f2196 Merge tag 'pull-work.dcache' of git://git.ker..
git tree: upstream
console+strace: https://syzkaller.appspot.com/x/log.txt?x=1446b746080000
kernel config: https://syzkaller.appspot.com/x/.config?x=a3f4d6985d3164cd
dashboard link: https://syzkaller.appspot.com/bug?extid=31c9594f6e43b9289b25
compiler: gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=106b302a080000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=16b1dae1080000

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+31c9594f6e43b9289b25@syzkaller.appspotmail.com

------------[ cut here ]------------
WARNING: CPU: 0 PID: 23016 at block/blk-mq.c:3881 blk_mq_release+0xf8/0x3e0 block/blk-mq.c:3881
Modules linked in:
CPU: 1 PID: 23016 Comm: syz-executor588 Not tainted 5.19.0-syzkaller-02972-g200e340f2196 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/22/2022
RIP: 0010:blk_mq_release+0xf8/0x3e0 block/blk-mq.c:3881
Code: fd 4c 8d a3 a8 02 00 00 4c 89 e0 48 c1 e8 03 80 3c 28 00 0f 85 14 02 00 00 48 8b 83 a8 02 00 00 49 39 c4 75 b1 e8 48 e4 96 fd <0f> 0b eb a8 e8 3f e4 96 fd 48 8b 44 24 10 48 05 18 05 00 00 48 89
RSP: 0018:ffffc900032bfc60 EFLAGS: 00010293
RAX: 0000000000000000 RBX: ffff88807a8e8800 RCX: 0000000000000000
RDX: ffff88807cd89d80 RSI: ffffffff83e3f578 RDI: 0000000000000000
RBP: dffffc0000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000001 R12: ffff88807a8e8aa8
R13: ffff88807ab0db40 R14: ffff88807ab0db88 R15: 0000000000000000
FS: 0000555555af3300(0000) GS:ffff8880b9b00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fbf573219f0 CR3: 000000007deea000 CR4: 0000000000350ee0
Call Trace:
<TASK>
blk_release_queue+0x153/0x270 block/blk-sysfs.c:780
kobject_cleanup lib/kobject.c:673 [inline]
kobject_release lib/kobject.c:704 [inline]
kref_put include/linux/kref.h:65 [inline]
kobject_put+0x1c8/0x540 lib/kobject.c:721
__alloc_disk_node+0x4f7/0x610 block/genhd.c:1388
__blk_mq_alloc_disk+0x13b/0x1f0 block/blk-mq.c:3961
loop_add+0x3e2/0xaf0 drivers/block/loop.c:1978
loop_control_ioctl+0x133/0x620 drivers/block/loop.c:2150
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:870 [inline]
__se_sys_ioctl fs/ioctl.c:856 [inline]
__x64_sys_ioctl+0x193/0x200 fs/ioctl.c:856
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7fbf572f20b9
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:00007ffca9b31288 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 0000000000000002 RCX: 00007fbf572f20b9
RDX: 000000000000000c RSI: 0000000000004c80 RDI: 0000000000000003
RBP: 00007ffca9b312a0 R08: 0000000000000002 R09: 0000000000000001
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000004
R13: 431bde82d7b634db R14: 0000000000000000 R15: 0000000000000000