[v5.15] WARNING in do_rmdir

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: ef251c45f1cd Linux 5.15.204
git tree: linux-5.15.y
console output: https://syzkaller.appspot.com/x/log.txt?x=161e8a73980000
kernel config: https://syzkaller.appspot.com/x/.config?x=353ae28c40b35af5
dashboard link: https://syzkaller.appspot.com/bug?extid=b392c0b60d575ca73a55
compiler: Debian clang version 21.1.8 (++20251221033036+2078da43e25a-1~exp1~20251221153213.50), Debian LLD 21.1.8

Unfortunately, I don't have any reproducer for this issue yet.

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/bde897c3d01f/disk-ef251c45.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/51b2a5826cd1/vmlinux-ef251c45.xz
kernel image: https://storage.googleapis.com/syzbot-assets/cb95a5a40121/bzImage-ef251c45.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+b392c0...@syzkaller.appspotmail.com

WARNING: CPU: 0 PID: 4285 at kernel/locking/rwsem.c:1350 __up_write kernel/locking/rwsem.c:1349 [inline]
WARNING: CPU: 0 PID: 4285 at kernel/locking/rwsem.c:1350 up_write+0x3a1/0x420 kernel/locking/rwsem.c:1604
Modules linked in:
CPU: 0 PID: 4285 Comm: syz.0.7 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
RIP: 0010:__up_write kernel/locking/rwsem.c:1349 [inline]
RIP: 0010:up_write+0x3a1/0x420 kernel/locking/rwsem.c:1604
Code: 44 d0 48 c7 c7 80 1b 2b 8a 48 c7 c6 40 1e 2b 8a 48 8b 14 24 4c 89 f1 4d 89 e0 4c 8b 4c 24 08 41 52 e8 73 6e 55 08 48 83 c4 08 <0f> 0b e9 6b fd ff ff 48 c7 c1 c8 23 8a 8d 80 e1 07 80 c1 03 38 c1
RSP: 0018:ffffc9000326fdb0 EFLAGS: 00010292
RAX: e644ca4a7a4b4f00 RBX: ffff888060744cf0 RCX: 0000000000080000
RDX: ffffc9000ea1a000 RSI: 0000000000008960 RDI: 0000000000008961
RBP: dffffc0000000000 R08: ffff8880b9033d7f R09: 1ffff110172067af
R10: dffffc0000000000 R11: ffffed10172067b0 R12: 0000000000000000
R13: ffff888060744d48 R14: ffff888060744cf0 R15: 1ffff1100c0e899f
FS: 00007fbcbc1c06c0(0000) GS:ffff8880b9100000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b32b20ff8 CR3: 000000002a11e000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
inode_unlock include/linux/fs.h:792 [inline]
do_rmdir+0x2d7/0x740 fs/namei.c:4222
__do_sys_unlinkat fs/namei.c:4398 [inline]
__se_sys_unlinkat fs/namei.c:4392 [inline]
__x64_sys_unlinkat+0xc0/0xe0 fs/namei.c:4392
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7fbcbdf87dd9
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:00007fbcbc1c0028 EFLAGS: 00000246 ORIG_RAX: 0000000000000107
RAX: ffffffffffffffda RBX: 00007fbcbe201090 RCX: 00007fbcbdf87dd9
RDX: 0000000000000200 RSI: 0000200000000000 RDI: ffffffffffffff9c
RBP: 00007fbcbe01dd69 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fbcbe201128 R14: 00007fbcbe201090 R15: 00007ffd3afda758
</TASK>


---
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If you want to undo deduplication, reply with:
#syz undup

[syzbot]

syzbot has found a reproducer for the following issue on:

HEAD commit: ef251c45f1cd Linux 5.15.204
git tree: linux-5.15.y

console output: https://syzkaller.appspot.com/x/log.txt?x=12dc3ace580000

kernel config: https://syzkaller.appspot.com/x/.config?x=353ae28c40b35af5
dashboard link: https://syzkaller.appspot.com/bug?extid=b392c0b60d575ca73a55
compiler: Debian clang version 21.1.8 (++20251221033036+2078da43e25a-1~exp1~20251221153213.50), Debian LLD 21.1.8

syz repro: https://syzkaller.appspot.com/x/repro.syz?x=1069516a580000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=10fe8a73980000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/bde897c3d01f/disk-ef251c45.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/51b2a5826cd1/vmlinux-ef251c45.xz
kernel image: https://storage.googleapis.com/syzbot-assets/cb95a5a40121/bzImage-ef251c45.xz

mounted in repro: https://storage.googleapis.com/syzbot-assets/50fa64eb8641/mount_0.gz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+b392c0...@syzkaller.appspotmail.com

------------[ cut here ]------------
DEBUG_RWSEMS_WARN_ON((rwsem_owner(sem) != current) && !rwsem_test_oflags(sem, RWSEM_NONSPINNABLE)): count = 0x0, magic = 0xffff8880587b5450, owner = 0x0, curr 0xffff88805c0fd940, list empty
WARNING: CPU: 0 PID: 4383 at kernel/locking/rwsem.c:1350 __up_write kernel/locking/rwsem.c:1349 [inline]
WARNING: CPU: 0 PID: 4383 at kernel/locking/rwsem.c:1350 up_write+0x3a1/0x420 kernel/locking/rwsem.c:1604
Modules linked in:
CPU: 0 PID: 4383 Comm: syz.1.23 Not tainted syzkaller #0

Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
RIP: 0010:__up_write kernel/locking/rwsem.c:1349 [inline]
RIP: 0010:up_write+0x3a1/0x420 kernel/locking/rwsem.c:1604
Code: 44 d0 48 c7 c7 80 1b 2b 8a 48 c7 c6 40 1e 2b 8a 48 8b 14 24 4c 89 f1 4d 89 e0 4c 8b 4c 24 08 41 52 e8 73 6e 55 08 48 83 c4 08 <0f> 0b e9 6b fd ff ff 48 c7 c1 c8 23 8a 8d 80 e1 07 80 c1 03 38 c1

RSP: 0018:ffffc9000341fdb0 EFLAGS: 00010292
RAX: 0f9c060e6b932400 RBX: ffff8880587b5450 RCX: ffff88805c0fd940
RDX: 0000000000000000 RSI: 0000000080000000 RDI: 0000000000000000

RBP: dffffc0000000000 R08: ffff8880b9033d7f R09: 1ffff110172067af
R10: dffffc0000000000 R11: ffffed10172067b0 R12: 0000000000000000

R13: ffff8880587b54a8 R14: ffff8880587b5450 R15: 1ffff1100b0f6a8b
FS: 00007ff5af1e76c0(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000

CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033

CR2: 00007f8f1d45ca08 CR3: 000000005be57000 CR4: 00000000003506f0

DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
inode_unlock include/linux/fs.h:792 [inline]
do_rmdir+0x2d7/0x740 fs/namei.c:4222
__do_sys_unlinkat fs/namei.c:4398 [inline]
__se_sys_unlinkat fs/namei.c:4392 [inline]
__x64_sys_unlinkat+0xc0/0xe0 fs/namei.c:4392
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x66/0xd0

RIP: 0033:0x7ff5afba6dd9

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:00007ff5af1e7028 EFLAGS: 00000246 ORIG_RAX: 0000000000000107
RAX: ffffffffffffffda RBX: 00007ff5afe20090 RCX: 00007ff5afba6dd9

RDX: 0000000000000200 RSI: 0000200000000000 RDI: ffffffffffffff9c

RBP: 00007ff5afc3cd69 R08: 0000000000000000 R09: 0000000000000000

R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000

R13: 00007ff5afe20128 R14: 00007ff5afe20090 R15: 00007fffd353e0f8
</TASK>


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