VFS: Found a Xenix FS (block size = 1024) on device loop4
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WARNING: CPU: 1 PID: 4488 at fs/inode.c:389 inc_nlink+0x120/0x130
Modules linked in:
CPU: 1 PID: 4488 Comm: syz.4.33 Tainted: G        W          6.1.122-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
RIP: 0010:inc_nlink+0x120/0x130 fs/inode.c:389
Code: e9 ff e9 37 ff ff ff 44 89 e9 80 e1 07 80 c1 03 38 c1 0f 8c 49 ff ff ff 4c 89 ef e8 aa eb e9 ff e9 3c ff ff ff e8 70 58 92 ff <0f> 0b eb 80 66 2e 0f 1f 84 00 00 00 00 00 66 90 41 57 41 56 53 48
RSP: 0018:ffffc90004a97d40 EFLAGS: 00010283
RAX: ffffffff81f84400 RBX: 1ffff1100ac63010 RCX: 0000000000080000
RDX: ffffc9000f95f000 RSI: 00000000000052d8 RDI: 00000000000052d9
RBP: 0000000000000000 R08: ffffffff81f8437a R09: ffffed1002fc2b57
R10: 0000000000000000 R11: dffffc0000000001 R12: dffffc0000000000
R13: ffff888056318080 R14: ffff888056318038 R15: 0000000000000000
FS:  00007f2f971486c0(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000020002000 CR3: 0000000057168000 CR4: 00000000003526e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 inode_inc_link_count include/linux/fs.h:2576 [inline]
 sysv_mkdir+0x1d/0x120 fs/sysv/namei.c:119
 vfs_mkdir+0x3b6/0x590 fs/namei.c:4106
 do_mkdirat+0x225/0x360 fs/namei.c:4131
 __do_sys_mkdirat fs/namei.c:4146 [inline]
 __se_sys_mkdirat fs/namei.c:4144 [inline]
 __x64_sys_mkdirat+0x85/0x90 fs/namei.c:4144
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f2f96384597
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:00007f2f97147e68 EFLAGS: 00000246 ORIG_RAX: 0000000000000102
RAX: ffffffffffffffda RBX: 00007f2f97147ef0 RCX: 00007f2f96384597
RDX: 00000000000001ff RSI: 00000000200000c0 RDI: 00000000ffffff9c
RBP: 0000000020000080 R08: 0000000020001f80 R09: 0000000000000000
R10: 0000000020000080 R11: 0000000000000246 R12: 00000000200000c0
R13: 00007f2f97147eb0 R14: 0000000000000000 R15: 0000000020000400
 </TASK>