[v5.15] WARNING in ovl_d_real (4)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: eceeec79dbc6 Linux 5.15.210
git tree: linux-5.15.y
console output: https://syzkaller.appspot.com/x/log.txt?x=1758d9ae580000
kernel config: https://syzkaller.appspot.com/x/.config?x=6a0cae3abafc69
dashboard link: https://syzkaller.appspot.com/bug?extid=b71de94c8c52558967f8
compiler: Debian clang version 22.1.6 (++20260514074242+fc4aad7b5db3-1~exp1~20260514074407.73), Debian LLD 22.1.6

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

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/a8f82a67235a/disk-eceeec79.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/f10abb6026a6/vmlinux-eceeec79.xz
kernel image: https://storage.googleapis.com/syzbot-assets/ade6c70761ba/bzImage-eceeec79.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+b71de9...@syzkaller.appspotmail.com

------------[ cut here ]------------
ovl_d_real(/file2, NULL:0): real dentry (ffff88805f6d5490/127) not found
WARNING: CPU: 0 PID: 4580 at fs/overlayfs/super.c:115 ovl_d_real+0x212/0x490 fs/overlayfs/super.c:112
Modules linked in:
CPU: 0 PID: 4580 Comm: syz.2.64 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
RIP: 0010:ovl_d_real+0x212/0x490 fs/overlayfs/super.c:112
Code: 36 45 31 ff 31 c0 48 c7 c7 80 2f 60 8a 48 c7 c6 9d 1f d6 8b 48 89 da 4c 89 e1 4d 89 f0 4d 89 f9 50 e8 42 e5 ed 06 48 83 c4 08 <0f> 0b 48 89 d8 5b 41 5c 41 5d 41 5e 41 5f 5d c3 e8 f9 ed b7 fe 49
RSP: 0018:ffffc90003a7f5c8 EFLAGS: 00010282
RAX: 4f084f5595647800 RBX: ffff888074a17608 RCX: 0000000000080000
RDX: ffffc9000f5ad000 RSI: 0000000000004bf1 RDI: 0000000000004bf2
RBP: dffffc0000000000 R08: ffff8880b902795b R09: 1ffff11017204f2b
R10: dffffc0000000000 R11: ffffed1017204f2c R12: ffffffff8a602fe0
R13: ffff8880289dd240 R14: 0000000000000000 R15: ffff88805f6d5490
FS: 00007f5e1268c6c0(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffc4c49e478 CR3: 00000000623a3000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
d_real include/linux/dcache.h:587 [inline]
d_real_inode include/linux/dcache.h:602 [inline]
process_measurement+0x18b5/0x1c20 security/integrity/ima/ima_main.c:283
ima_file_check+0xc7/0x110 security/integrity/ima/ima_main.c:533
do_open fs/namei.c:3618 [inline]
path_openat+0x27cf/0x2fb0 fs/namei.c:3750
do_filp_open+0x1df/0x400 fs/namei.c:3777
do_sys_openat2+0x14b/0x500 fs/open.c:1255
do_sys_open fs/open.c:1271 [inline]
__do_sys_openat fs/open.c:1287 [inline]
__se_sys_openat fs/open.c:1282 [inline]
__x64_sys_openat+0x135/0x160 fs/open.c:1282
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: 0033:0x7f5e14453e59
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:00007f5e1268c028 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007f5e146cd090 RCX: 00007f5e14453e59
RDX: 0000000000000000 RSI: 0000200000000340 RDI: ffffffffffffff9c
RBP: 00007f5e144e9e6f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000012 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f5e146cd128 R14: 00007f5e146cd090 R15: 00007ffd6d061698
</TASK>


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