[v5.15] kernel BUG in ocfs2_search_chain

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: c79648372d02 Linux 5.15.189
git tree: linux-5.15.y
console output: https://syzkaller.appspot.com/x/log.txt?x=17588ef0580000
kernel config: https://syzkaller.appspot.com/x/.config?x=9e47345638b85bd0
dashboard link: https://syzkaller.appspot.com/bug?extid=117e60460e7d5bd2fc02
compiler: Debian clang version 20.1.7 (++20250616065708+6146a88f6049-1~exp1~20250616065826.132), Debian LLD 20.1.7
userspace arch: arm64

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

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/7ab49562317a/disk-c7964837.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/e847ec1e38d3/vmlinux-c7964837.xz
kernel image: https://storage.googleapis.com/syzbot-assets/263158c6371c/Image-c7964837.gz.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+117e60...@syzkaller.appspotmail.com

------------[ cut here ]------------
kernel BUG at fs/ocfs2/suballoc.c:1349!
Internal error: Oops - BUG: 00000000f2000800 [#1] PREEMPT SMP
Modules linked in:
CPU: 1 PID: 4334 Comm: syz.3.43 Not tainted 5.15.189-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/30/2025
pstate: 62400005 (nZCv daif +PAN -UAO +TCO -DIT -SSBS BTYPE=--)
pc : ocfs2_block_group_set_bits+0x4d0/0x640 fs/ocfs2/suballoc.c:1349
lr : ocfs2_block_group_set_bits+0x4d0/0x640 fs/ocfs2/suballoc.c:1349
sp : ffff80001fef5b40
x29: ffff80001fef5bc0 x28: ffff80001fef5f9c x27: ffff0000dd2de000
x26: 000000000000003d x25: ffff0000e82f500c x24: ffff0000dee216b8
x23: dfff800000000000 x22: 00000000000003b5 x21: 0000000000000040
x20: 1ffff00003fdeb6c x19: ffff0000e82f5000 x18: 0000000000000000
x17: 0000000000000002 x16: ffff800009cdac40 x15: 00000000fffffffc
x14: 0000000000ff0100 x13: ffffffffffffffff x12: 0000000000080000
x11: 000000000007ffff x10: ffff80002693c000 x9 : ffff800009cd0eb0
x8 : 0000000000080000 x7 : ffff800008ddb3a4 x6 : 0000000000000000
x5 : 0000000000000040 x4 : 00000000000003b5 x3 : ffff0000dd2de000
x2 : ffff0000e82f5000 x1 : 000000000000003d x0 : 0000000000000040
Call trace:
ocfs2_block_group_set_bits+0x4d0/0x640 fs/ocfs2/suballoc.c:1349
ocfs2_search_chain+0x144c/0x1f08 fs/ocfs2/suballoc.c:1847
ocfs2_claim_suballoc_bits+0x8f8/0x1b74 fs/ocfs2/suballoc.c:1930
__ocfs2_claim_clusters+0x26c/0x7e0 fs/ocfs2/suballoc.c:2338
ocfs2_claim_clusters fs/ocfs2/suballoc.c:2375 [inline]
ocfs2_block_group_alloc_contig fs/ocfs2/suballoc.c:428 [inline]
ocfs2_block_group_alloc fs/ocfs2/suballoc.c:695 [inline]
ocfs2_reserve_suballoc_bits+0xb88/0x3a68 fs/ocfs2/suballoc.c:828
ocfs2_reserve_new_metadata_blocks+0x34c/0x7d8 fs/ocfs2/suballoc.c:978
ocfs2_reserve_new_metadata fs/ocfs2/suballoc.c:1021 [inline]
ocfs2_lock_allocators+0x248/0x518 fs/ocfs2/suballoc.c:2658
ocfs2_extend_allocation+0x328/0x1504 fs/ocfs2/file.c:588
ocfs2_extend_no_holes+0x1a8/0x424 fs/ocfs2/file.c:1030
ocfs2_expand_nonsparse_inode+0x12c/0x394 fs/ocfs2/aops.c:1622
ocfs2_write_begin_nolock+0xe14/0x3764 fs/ocfs2/aops.c:1688
ocfs2_write_begin+0x1b4/0x30c fs/ocfs2/aops.c:1905
generic_perform_write+0x204/0x480 mm/filemap.c:3785
__generic_file_write_iter+0x23c/0x454 mm/filemap.c:3912
ocfs2_file_write_iter+0x12e0/0x1b84 fs/ocfs2/file.c:2472
call_write_iter include/linux/fs.h:2172 [inline]
new_sync_write fs/read_write.c:507 [inline]
vfs_write+0x7c8/0xa2c fs/read_write.c:594
ksys_write+0x120/0x210 fs/read_write.c:647
__do_sys_write fs/read_write.c:659 [inline]
__se_sys_write fs/read_write.c:656 [inline]
__arm64_sys_write+0x7c/0x90 fs/read_write.c:656
__invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:52
el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142
do_el0_svc+0x58/0x14c arch/arm64/kernel/syscall.c:181
el0_svc+0x78/0x1e0 arch/arm64/kernel/entry-common.c:608
el0t_64_sync_handler+0xcc/0xe4 arch/arm64/kernel/entry-common.c:626
el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584
Code: 17ffff67 979ea157 d4210000 979ea155 (d4210000)
---[ end trace 99ee4a409304ae7d ]---


---
This report is generated by a bot. It may contain errors.
See https://goo.gl/tpsmEJ for more information about syzbot.
syzbot engineers can be reached at syzk...@googlegroups.com.

syzbot will keep track of this issue. See:
https://goo.gl/tpsmEJ#status for how to communicate with syzbot.

If the report is already addressed, let syzbot know by replying with:
#syz fix: exact-commit-title

If you want to overwrite report's subsystems, reply with:
#syz set subsystems: new-subsystem
(See the list of subsystem names on the web dashboard)

If the report is a duplicate of another one, reply with:
#syz dup: exact-subject-of-another-report

If you want to undo deduplication, reply with:
#syz undup

[syzbot]

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