syzbot


WARNING in ovl_workdir_create (4)

Status: upstream: reported on 2026/01/19 15:15
Reported-by: syzbot+ec361ade46804ec0d151@syzkaller.appspotmail.com
First crash: 13d, last: 11h33m
Similar bugs (11)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-5.15 WARNING in ovl_workdir_create (3) -1 2 184d 184d 0/3 auto-obsoleted due to no activity on 2025/11/09 02:42
upstream WARNING in ovl_workdir_create overlayfs -1 1 1138d 1134d 0/29 auto-obsoleted due to no activity on 2023/04/20 02:11
upstream WARNING in ovl_workdir_create (3) ext4 -1 1 633d 629d 0/29 auto-obsoleted due to no activity on 2024/08/17 18:22
linux-6.1 WARNING in ovl_workdir_create (3) -1 4 148d 268d 0/3 auto-obsoleted due to no activity on 2025/12/15 10:43
upstream WARNING in ovl_workdir_create (4) overlayfs -1 1 433d 429d 0/29 auto-obsoleted due to no activity on 2025/01/24 06:35
linux-6.1 WARNING in ovl_workdir_create (2) -1 2 409d 425d 0/3 auto-obsoleted due to no activity on 2025/03/29 20:32
linux-5.15 WARNING in ovl_workdir_create -1 3 434d 586d 0/3 auto-obsoleted due to no activity on 2025/03/04 23:52
upstream WARNING in ovl_workdir_create (5) overlayfs -1 4 81d 144d 0/29 upstream: reported on 2025/09/10 17:53
linux-5.15 WARNING in ovl_workdir_create (2) -1 1 304d 304d 0/3 auto-obsoleted due to no activity on 2025/07/12 19:53
linux-6.1 WARNING in ovl_workdir_create -1 1 625d 625d 0/3 auto-obsoleted due to no activity on 2024/08/25 13:40
upstream WARNING in ovl_workdir_create (2) overlayfs -1 1 814d 810d 0/29 auto-obsoleted due to no activity on 2024/02/18 01:53

Sample crash report:
------------[ cut here ]------------
DEBUG_RWSEMS_WARN_ON((rwsem_owner(sem) != current) && !rwsem_test_oflags(sem, RWSEM_NONSPINNABLE)): count = 0x0, magic = 0xffff8880444b71d0, owner = 0x0, curr 0xffff88807e280000, list empty
WARNING: CPU: 0 PID: 6469 at kernel/locking/rwsem.c:1372 __up_write kernel/locking/rwsem.c:1371 [inline]
WARNING: CPU: 0 PID: 6469 at kernel/locking/rwsem.c:1372 up_write+0x3a1/0x420 kernel/locking/rwsem.c:1626
Modules linked in:
CPU: 0 PID: 6469 Comm: syz.6.648 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:__up_write kernel/locking/rwsem.c:1371 [inline]
RIP: 0010:up_write+0x3a1/0x420 kernel/locking/rwsem.c:1626
Code: 44 d0 48 c7 c7 a0 05 8c 8a 48 c7 c6 e0 07 8c 8a 48 8b 14 24 4c 89 f1 4d 89 e0 4c 8b 4c 24 08 41 52 e8 f3 30 ea ff 48 83 c4 08 <0f> 0b e9 6b fd ff ff 48 c7 c1 e8 f7 1f 8e 80 e1 07 80 c1 03 38 c1
RSP: 0018:ffffc9000c38f750 EFLAGS: 00010296
RAX: 3ab1abb70e644c00 RBX: ffff8880444b71d0 RCX: 0000000000080000
RDX: ffffc9000f9ed000 RSI: 0000000000022ce7 RDI: 0000000000022ce8
RBP: dffffc0000000000 R08: ffffc9000c38f447 R09: 1ffff92001871e88
R10: dffffc0000000000 R11: fffff52001871e89 R12: 0000000000000000
R13: ffff8880444b7228 R14: ffff8880444b71d0 R15: 1ffff11008896e3b
FS:  00007f451f8836c0(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f451e9e8600 CR3: 0000000020385000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 inode_unlock include/linux/fs.h:763 [inline]
 ovl_workdir_create+0x6ac/0x760 fs/overlayfs/super.c:842
 ovl_make_workdir fs/overlayfs/super.c:1389 [inline]
 ovl_get_workdir+0x3c6/0x1610 fs/overlayfs/super.c:1539
 ovl_fill_super+0x1824/0x2a30 fs/overlayfs/super.c:2095
 mount_nodev+0x52/0xe0 fs/super.c:1489
 legacy_get_tree+0xe6/0x180 fs/fs_context.c:632
 vfs_get_tree+0x88/0x270 fs/super.c:1573
 do_new_mount+0x24a/0xa40 fs/namespace.c:3078
 do_mount fs/namespace.c:3421 [inline]
 __do_sys_mount fs/namespace.c:3629 [inline]
 __se_sys_mount+0x2e3/0x3d0 fs/namespace.c:3606
 do_syscall_x64 arch/x86/entry/common.c:46 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f451e99aeb9
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 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 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f451f883028 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007f451ec16090 RCX: 00007f451e99aeb9
RDX: 0000200000000440 RSI: 0000200000000100 RDI: 0000000000000000
RBP: 00007f451ea08c1f R08: 0000200000000080 R09: 0000000000000000
R10: 0000000000000008 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f451ec16128 R14: 00007f451ec16090 R15: 00007ffcc4b63db8
 </TASK>

Crashes (3):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/02/01 13:31 linux-6.1.y cd9b81672742 6b8752f2 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan WARNING in ovl_workdir_create
2026/01/24 00:01 linux-6.1.y cd9b81672742 4f25b9b4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan WARNING in ovl_workdir_create
2026/01/19 15:14 linux-6.1.y cd9b81672742 a9fc5226 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan WARNING in ovl_workdir_create
* Struck through repros no longer work on HEAD.