[v6.1] kernel BUG in ocfs2_populate_inode

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: ad16b162f21d Linux 6.1.172
git tree: linux-6.1.y
console output: https://syzkaller.appspot.com/x/log.txt?x=1221a3ce580000
kernel config: https://syzkaller.appspot.com/x/.config?x=b1adc0bfde2d8a4a
dashboard link: https://syzkaller.appspot.com/bug?extid=9461958fcca348fee7bc
compiler: Debian clang version 21.1.8 (++20251221033036+2078da43e25a-1~exp1~20251221153213.50), Debian LLD 21.1.8
userspace arch: arm64
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=1005ebce580000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=17993ad2580000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/01975838d01a/disk-ad16b162.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/025b6eac2853/vmlinux-ad16b162.xz
kernel image: https://storage.googleapis.com/syzbot-assets/4defc266eb64/Image-ad16b162.gz.xz
mounted in repro: https://storage.googleapis.com/syzbot-assets/71890a85c6cc/mount_0.gz
fsck result: OK (log: https://syzkaller.appspot.com/x/fsck.log?x=11a6b7ce580000)

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+946195...@syzkaller.appspotmail.com

loop0: detected capacity change from 0 to 32768
------------[ cut here ]------------
kernel BUG at fs/ocfs2/inode.c:336!
Internal error: Oops - BUG: 00000000f2000800 [#1] PREEMPT SMP
Modules linked in:
CPU: 0 PID: 4521 Comm: syz.0.17 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026
pstate: 82400005 (Nzcv daif +PAN -UAO +TCO -DIT -SSBS BTYPE=--)
pc : ocfs2_populate_inode+0x14ec/0x1570 fs/ocfs2/inode.c:336
lr : ocfs2_populate_inode+0x14ec/0x1570 fs/ocfs2/inode.c:336
sp : ffff8000213f6b60
x29: ffff8000213f6c60 x28: ffff0000f2396e2c x27: 1fffe0001e472dc5
x26: ffff0000f2396e50 x25: 1fffe0001e472dca x24: ffff70000427ed80
x23: ffff80001521d160 x22: ffff0000f2396e00 x21: dfff800000000000
x20: 0000000000000031 x19: ffff0000e55ecfb8 x18: ffff800011b9bf60
x17: 1fffe00033ea637e x16: ffff8000082d92bc x15: 0000000000000000
x14: 0000000000000001 x13: 1fffe0001cabda36 x12: 0000000000ff0100
x11: ff00800009d71350 x10: 0000000000000000 x9 : ffff800009d71350
x8 : ffff0000c60b0000 x7 : ffff800008257984 x6 : 0000000000000000
x5 : 0000000000000080 x4 : 0000000000000001 x3 : ffff800009d700e0
x2 : 0000000000000001 x1 : 0000000000000020 x0 : 0000000000000000
Call trace:
ocfs2_populate_inode+0x14ec/0x1570 fs/ocfs2/inode.c:336
ocfs2_read_locked_inode fs/ocfs2/inode.c:542 [inline]
ocfs2_iget+0xb84/0x1a20 fs/ocfs2/inode.c:159
_ocfs2_get_system_file_inode fs/ocfs2/sysfile.c:142 [inline]
ocfs2_get_system_file_inode+0x2e8/0x690 fs/ocfs2/sysfile.c:112
ocfs2_init_global_system_inodes+0x2a0/0x5c8 fs/ocfs2/super.c:457
ocfs2_initialize_super fs/ocfs2/super.c:2253 [inline]
ocfs2_fill_super+0x2408/0x436c fs/ocfs2/super.c:994
mount_bdev+0x264/0x358 fs/super.c:1443
ocfs2_mount+0x44/0x58 fs/ocfs2/super.c:1186
legacy_get_tree+0xd4/0x16c fs/fs_context.c:632
vfs_get_tree+0x90/0x274 fs/super.c:1573
do_new_mount+0x228/0x810 fs/namespace.c:3078
path_mount+0x5bc/0xe80 fs/namespace.c:3408
do_mount fs/namespace.c:3421 [inline]
__do_sys_mount fs/namespace.c:3629 [inline]
__se_sys_mount fs/namespace.c:3606 [inline]
__arm64_sys_mount+0x49c/0x59c fs/namespace.c:3606
__invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
invoke_syscall+0x98/0x2b4 arch/arm64/kernel/syscall.c:52
el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:140
do_el0_svc+0x58/0x130 arch/arm64/kernel/syscall.c:204
el0_svc+0x58/0x128 arch/arm64/kernel/entry-common.c:637
el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655
el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585
Code: f9403bfc f9404bfb 17fffcda 979ce8b3 (d4210000)
---[ end trace 0000000000000000 ]---


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