[moderation] [fs?] WARNING in do_new_mount (3)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 8155b4ef3466 Add linux-next specific files for 20241220
git tree: linux-next
console output: https://syzkaller.appspot.com/x/log.txt?x=114b7818580000
kernel config: https://syzkaller.appspot.com/x/.config?x=9c90bb7161a56c88
dashboard link: https://syzkaller.appspot.com/bug?extid=2533f26c46e80b622d5d
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
CC: [bra...@kernel.org ja...@suse.cz linux-...@vger.kernel.org linux-...@vger.kernel.org vi...@zeniv.linux.org.uk]

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

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/98a974fc662d/disk-8155b4ef.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/2dea9b72f624/vmlinux-8155b4ef.xz
kernel image: https://storage.googleapis.com/syzbot-assets/593a42b9eb34/bzImage-8155b4ef.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+2533f2...@syzkaller.appspotmail.com

------------[ cut here ]------------
DEBUG_RWSEMS_WARN_ON((rwsem_owner(sem) != current) && !rwsem_test_oflags(sem, RWSEM_NONSPINNABLE)): count = 0x0, magic = 0xffff88804d72bd08, owner = 0x0, curr 0xffff88805d988000, list empty
WARNING: CPU: 1 PID: 12717 at kernel/locking/rwsem.c:1368 __up_write kernel/locking/rwsem.c:1367 [inline]
WARNING: CPU: 1 PID: 12717 at kernel/locking/rwsem.c:1368 up_write+0x502/0x590 kernel/locking/rwsem.c:1630
Modules linked in:
CPU: 1 UID: 0 PID: 12717 Comm: syz.2.1246 Not tainted 6.13.0-rc3-next-20241220-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
RIP: 0010:__up_write kernel/locking/rwsem.c:1367 [inline]
RIP: 0010:up_write+0x502/0x590 kernel/locking/rwsem.c:1630
Code: c7 c7 c0 8d 0a 8c 48 c7 c6 e0 8f 0a 8c 48 8b 54 24 28 48 8b 4c 24 18 4d 89 e0 4c 8b 4c 24 30 53 e8 c3 16 e6 ff 48 83 c4 08 90 <0f> 0b 90 90 e9 6a fd ff ff 48 c7 c1 94 e4 1a 90 80 e1 07 80 c1 03
RSP: 0018:ffffc900053a7c60 EFLAGS: 00010296
RAX: 8687e302171d8200 RBX: ffffffff8c0a8ea0 RCX: 0000000000080000
RDX: ffffc9000d7ac000 RSI: 000000000000754f RDI: 0000000000007550
RBP: ffffc900053a7d30 R08: ffffffff817feaa2 R09: fffffbfff1cfa1a8
R10: dffffc0000000000 R11: fffffbfff1cfa1a8 R12: 0000000000000000
R13: ffff88804d72bd08 R14: 1ffff92000a74f94 R15: dffffc0000000000
FS: 00007f79062ff6c0(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000000 CR3: 000000007e390000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
inode_unlock include/linux/fs.h:868 [inline]
unlock_mount fs/namespace.c:2710 [inline]
do_new_mount_fc fs/namespace.c:3499 [inline]
do_new_mount+0x88e/0xb40 fs/namespace.c:3558
do_mount fs/namespace.c:3896 [inline]
__do_sys_mount fs/namespace.c:4107 [inline]
__se_sys_mount+0x2d6/0x3c0 fs/namespace.c:4084
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: 0033:0x7f7905585d29
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f79062ff038 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007f7905776240 RCX: 00007f7905585d29
RDX: 0000000020000040 RSI: 0000000020000380 RDI: 0000000000000000
RBP: 00007f7905601b08 R08: 0000000020000400 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f7905776240 R15: 00007fff7f6f7c78
</TASK>


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[syzbot]

Auto-closing this bug as obsolete.
Crashes did not happen for a while, no reproducer and no activity.