[syzbot] [ext4?] WARNING in lock_two_nondirectories

syzbot
2023-12-15T13:49:22Z

Hello,

syzbot found the following issue on:

HEAD commit: a39b6ac3781d Linux 6.7-rc5
git tree: upstream
console+strace: https://syzkaller.appspot.com/x/log.txt?x=12c3a112e80000
kernel config: https://syzkaller.appspot.com/x/.config?x=e043d554f0a5f852
dashboard link: https://syzkaller.appspot.com/bug?extid=2c4a3b922a860084cc7f
compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=1687292ee80000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=16d8adbce80000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/67fd20dff9bc/disk-a39b6ac3.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/778677113ec4/vmlinux-a39b6ac3.xz
kernel image: https://storage.googleapis.com/syzbot-assets/fd69b2e7d493/bzImage-a39b6ac3.xz
mounted in repro: https://storage.googleapis.com/syzbot-assets/28ab13ef564b/mount_0.gz

Bisection is inconclusive: the issue happens on the oldest tested release.

bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=1286a2b2e80000
final oops: https://syzkaller.appspot.com/x/report.txt?x=1186a2b2e80000
console output: https://syzkaller.appspot.com/x/log.txt?x=1686a2b2e80000

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+2c4a3b922a860084cc7f@syzkaller.appspotmail.com

EXT4-fs (loop0): mounted filesystem 00000000-0000-0000-0000-000000000000 r/w without journal. Quota mode: none.
------------[ cut here ]------------
WARNING: CPU: 1 PID: 5067 at fs/inode.c:1148 lock_two_nondirectories+0xca/0x100 fs/inode.c:1148
Modules linked in:
CPU: 1 PID: 5067 Comm: syz-executor207 Not tainted 6.7.0-rc5-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/10/2023
RIP: 0010:lock_two_nondirectories+0xca/0x100 fs/inode.c:1148
Code: ff 66 41 81 fc 00 40 74 1b e8 c2 3d 92 ff 48 89 ee 48 89 df 5b 5d b9 04 00 00 00 31 d2 41 5c e9 5c fd ff ff e8 a7 3d 92 ff 90 <0f> 0b 90 eb da e8 9c 3d 92 ff 90 0f 0b 90 eb 83 48 89 df e8 5e e4
RSP: 0018:ffffc90003a4fc38 EFLAGS: 00010293
RAX: 0000000000000000 RBX: ffff88807cf82ab0 RCX: ffffffff81f55031
RDX: ffff888078b21dc0 RSI: ffffffff81f55059 RDI: 0000000000000003
RBP: ffff88807cfe66b0 R08: 0000000000000003 R09: 0000000000004000
R10: 0000000000004000 R11: ffffffff915fc8a0 R12: 0000000000004000
R13: ffff8880298d2c80 R14: ffff88807cfe66b0 R15: ffffffff8d195740
FS: 0000555555d51380(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000000 CR3: 0000000056e5a000 CR4: 0000000000350ef0
Call Trace:
<TASK>
swap_inode_boot_loader fs/ext4/ioctl.c:391 [inline]
__ext4_ioctl+0x118d/0x4570 fs/ext4/ioctl.c:1437
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:871 [inline]
__se_sys_ioctl fs/ioctl.c:857 [inline]
__x64_sys_ioctl+0x18f/0x210 fs/ioctl.c:857
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0x40/0x110 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x63/0x6b
RIP: 0033:0x7f61c40c4af9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 61 17 00 00 90 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 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffe0eaa3fb8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007ffe0eaa4198 RCX: 00007f61c40c4af9
RDX: 0000000000000000 RSI: 0000000000006611 RDI: 0000000000000004
RBP: 00007f61c4138610 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001
R13: 00007ffe0eaa4188 R14: 0000000000000001 R15: 0000000000000001
</TASK>

---
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