syzbot


WARNING in do_mkdirat (4)

Status: upstream: reported on 2025/08/24 17:03
Reported-by: syzbot+74a4f4ba4b285cd37691@syzkaller.appspotmail.com
First crash: 113d, last: 5d17h
Similar bugs (6)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-6.1 WARNING in do_mkdirat (3) -1 16 236d 304d 0/3 auto-obsoleted due to no activity on 2025/07/02 00:38
linux-6.1 WARNING in do_mkdirat -1 7 756d 980d 0/3 auto-obsoleted due to no activity on 2024/02/28 16:21
linux-6.1 WARNING in do_mkdirat (2) -1 60 376d 628d 0/3 auto-obsoleted due to no activity on 2025/02/12 20:24
linux-6.6 WARNING in do_mkdirat -1 1 84d 84d 0/2 upstream: reported on 2025/09/22 18:38
upstream WARNING in do_mkdirat fs -1 C error error 657 2h02m 1108d 0/29 upstream: reported C repro on 2022/12/03 14:52
linux-5.15 WARNING in do_mkdirat origin:lts-only -1 C inconclusive 21 56d 894d 0/3 upstream: reported C repro on 2023/07/05 09:42

Sample crash report:
------------[ cut here ]------------
DEBUG_RWSEMS_WARN_ON((rwsem_owner(sem) != current) && !rwsem_test_oflags(sem, RWSEM_NONSPINNABLE)): count = 0x0, magic = 0xffff888072b56a70, owner = 0x0, curr 0xffff888027890000, list empty
WARNING: CPU: 1 PID: 4778 at kernel/locking/rwsem.c:1372 __up_write kernel/locking/rwsem.c:1371 [inline]
WARNING: CPU: 1 PID: 4778 at kernel/locking/rwsem.c:1372 up_write+0x3a1/0x420 kernel/locking/rwsem.c:1626
Modules linked in:
CPU: 1 PID: 4778 Comm: syz.2.102 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 80 f9 6b 8a 48 c7 c6 c0 fb 6b 8a 48 8b 14 24 4c 89 f1 4d 89 e0 4c 8b 4c 24 08 41 52 e8 b3 83 ea ff 48 83 c4 08 <0f> 0b e9 6b fd ff ff 48 c7 c1 e8 42 ff 8d 80 e1 07 80 c1 03 38 c1
RSP: 0018:ffffc9000344fdf0 EFLAGS: 00010296
RAX: 6a80c80701a95f00 RBX: ffff888072b56a70 RCX: 0000000000080000
RDX: ffffc9000f2ab000 RSI: 0000000000013021 RDI: 0000000000013022
RBP: dffffc0000000000 R08: dffffc0000000000 R09: fffff52000689f4d
R10: fffff52000689f4d R11: 1ffff92000689f4c R12: 0000000000000000
R13: ffff888072b56ac8 R14: ffff888072b56a70 R15: 1ffff1100e56ad4f
FS:  00007feb9dfd56c0(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f870b40d000 CR3: 000000005bca0000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 inode_unlock include/linux/fs.h:763 [inline]
 done_path_create fs/namei.c:3935 [inline]
 do_mkdirat+0x212/0x430 fs/namei.c:4142
 __do_sys_mkdirat fs/namei.c:4154 [inline]
 __se_sys_mkdirat fs/namei.c:4152 [inline]
 __x64_sys_mkdirat+0x85/0x90 fs/namei.c:4152
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7feb9fd8de97
Code: 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 b8 02 01 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007feb9dfd4e68 EFLAGS: 00000246 ORIG_RAX: 0000000000000102
RAX: ffffffffffffffda RBX: 00007feb9dfd4ef0 RCX: 00007feb9fd8de97
RDX: 00000000000001ff RSI: 00002000000000c0 RDI: 00000000ffffff9c
RBP: 0000000000000000 R08: 0000200000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00002000000000c0
R13: 00007feb9dfd4eb0 R14: 0000000000000000 R15: 0000000000000000
 </TASK>

Crashes (8):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/12/09 20:05 linux-6.1.y 50cbba13faa2 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan WARNING in do_mkdirat
2025/10/26 21:07 linux-6.1.y 8e6e2188d949 c0460fcd .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan WARNING in do_mkdirat
2025/08/24 17:03 linux-6.1.y 0bc96de781b4 bf27483f .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan WARNING in do_mkdirat
2025/12/10 02:48 linux-6.1.y 50cbba13faa2 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 WARNING in do_mkdirat
2025/12/06 08:53 linux-6.1.y f6e38ae624cf d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 WARNING in do_mkdirat
2025/12/06 02:04 linux-6.1.y f6e38ae624cf d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 WARNING in do_mkdirat
2025/12/02 20:16 linux-6.1.y f6e38ae624cf d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 WARNING in do_mkdirat
2025/11/27 21:03 linux-6.1.y f6e38ae624cf d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 WARNING in do_mkdirat
* Struck through repros no longer work on HEAD.