syzbot


WARNING: bad unlock balance in sd_revalidate_disk

Status: upstream: reported syz repro on 2024/11/06 02:51
Subsystems: scsi usb
[Documentation on labels]
Reported-by: syzbot+331e232a5d7a69fa7c81@syzkaller.appspotmail.com
First crash: 35d, last: 34d
Discussions (1)
Title Replies (including bot) Last reply
[syzbot] [usb?] [scsi?] WARNING: bad unlock balance in sd_revalidate_disk 1 (3) 2024/11/06 09:39
Last patch testing requests (2)
Created Duration User Patch Repo Result
2024/11/16 22:34 10m retest repro linux-next error
2024/11/06 09:09 28m ming.lei@redhat.com https://github.com/ming1/linux.git for-next OK log

Sample crash report:
sd 2:0:0:1: [sdc] Test Unit Ready failed: Result: hostbyte=DID_NO_CONNECT driverbyte=DRIVER_OK
=====================================
WARNING: bad unlock balance detected!
6.12.0-rc5-next-20241101-syzkaller #0 Not tainted
-------------------------------------
udevd/5897 is trying to release lock (&q->q_usage_counter(queue)) at:
[<ffffffff862f40d3>] sd_revalidate_disk+0x7933/0xbcf0 drivers/scsi/sd.c:3808
but there are no more locks to release!

other info that might help us debug this:
1 lock held by udevd/5897:
 #0: ffff8881433c14c8 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xf0/0xc50 block/bdev.c:904

stack backtrace:
CPU: 1 UID: 0 PID: 5897 Comm: udevd Not tainted 6.12.0-rc5-next-20241101-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120
 print_unlock_imbalance_bug+0x25b/0x2d0 kernel/locking/lockdep.c:5287
 __lock_release kernel/locking/lockdep.c:5526 [inline]
 lock_release+0x5cb/0xa30 kernel/locking/lockdep.c:5870
 blk_unfreeze_release_lock block/blk.h:745 [inline]
 blk_mq_unfreeze_queue+0xd2/0x140 block/blk-mq.c:213
 sd_revalidate_disk+0x7933/0xbcf0 drivers/scsi/sd.c:3808
 sd_open+0x21e/0x610 drivers/scsi/sd.c:1534
 blkdev_get_whole+0x8e/0x450 block/bdev.c:689
 bdev_open+0x2d4/0xc50 block/bdev.c:916
 blkdev_open+0x389/0x4f0 block/fops.c:627
 do_dentry_open+0xbe1/0x1b70 fs/open.c:962
 vfs_open+0x3e/0x330 fs/open.c:1092
 do_open fs/namei.c:3774 [inline]
 path_openat+0x2c84/0x3590 fs/namei.c:3933
 do_filp_open+0x235/0x490 fs/namei.c:3960
 do_sys_openat2+0x13e/0x1d0 fs/open.c:1419
 do_sys_open fs/open.c:1434 [inline]
 __do_sys_openat fs/open.c:1450 [inline]
 __se_sys_openat fs/open.c:1445 [inline]
 __x64_sys_openat+0x247/0x2a0 fs/open.c:1445
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f64b7d169a4
Code: 24 20 48 8d 44 24 30 48 89 44 24 28 64 8b 04 25 18 00 00 00 85 c0 75 2c 44 89 e2 48 89 ee bf 9c ff ff ff b8 01 01 00 00 0f 05 <48> 3d 00 f0 ff ff 76 60 48 8b 15 55 a4 0d 00 f7 d8 64 89 02 48 83
RSP: 002b:00007ffcdb024940 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00005623a7271270 RCX: 00007f64b7d169a4
RDX: 00000000000a0800 RSI: 00005623a725b4e0 RDI: 00000000ffffff9c
RBP: 00005623a725b4e0 R08: 0000000000000006 R09: 7fffffffffffffff
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000000a0800
R13: 00005623a726ee60 R14: 0000000000000001 R15: 00005623a724f910
 </TASK>
udevd[5897]: inotify_add_watch(7, /dev/sdc, 10) failed: No such file or directory

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/11/02 22:17 linux-next c88416ba074a f00eed24 .config console log report syz / log [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root WARNING: bad unlock balance in sd_revalidate_disk
2024/11/02 02:40 linux-next c88416ba074a f00eed24 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root WARNING: bad unlock balance in sd_revalidate_disk
* Struck through repros no longer work on HEAD.