[syzbot] [block?] kernel BUG in bio_chain

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: b2c27842ba85 Add linux-next specific files for 20251203
git tree: linux-next
console output: https://syzkaller.appspot.com/x/log.txt?x=1688d2b4580000
kernel config: https://syzkaller.appspot.com/x/.config?x=caadf525b0ab8d17
dashboard link: https://syzkaller.appspot.com/bug?extid=f6539d4ce3f775aee0cc
compiler: Debian clang version 20.1.8 (++20250708063551+0c9f909b7976-1~exp1~20250708183702.136), Debian LLD 20.1.8
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=13dd5512580000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=158d7512580000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/1168b2ea1fd1/disk-b2c27842.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/2c3066faf780/vmlinux-b2c27842.xz
kernel image: https://storage.googleapis.com/syzbot-assets/f6693abe374d/bzImage-b2c27842.xz
mounted in repro: https://storage.googleapis.com/syzbot-assets/caedad91e176/mount_0.gz
fsck result: failed (log: https://syzkaller.appspot.com/x/fsck.log?x=118d7512580000)

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+f6539d...@syzkaller.appspotmail.com

gfs2: fsid=syz:syz.0: jid=0, already locked for use
gfs2: fsid=syz:syz.0: jid=0: Looking at journal...
------------[ cut here ]------------
kernel BUG at block/bio.c:342!
Oops: invalid opcode: 0000 [#1] SMP KASAN PTI
CPU: 1 UID: 0 PID: 912 Comm: kworker/1:2 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
Workqueue: gfs2_recovery gfs2_recover_func
RIP: 0010:bio_chain+0xee/0x100 block/bio.c:342
Code: 43 1c 5b 41 5c 41 5d 41 5e 41 5f 5d e9 1b e1 f2 06 cc 89 f9 80 e1 07 fe c1 38 c1 7c cf e8 aa fc bd fd eb c8 e8 d3 a8 57 fd 90 <0f> 0b e8 cb a8 57 fd 90 0f 0b 0f 1f 84 00 00 00 00 00 90 90 90 90
RSP: 0018:ffffc90003d07540 EFLAGS: 00010293
RAX: ffffffff846a0a5d RBX: ffff8880207223c0 RCX: ffff888025b49e80
RDX: 0000000000000000 RSI: ffff8880207223c0 RDI: ffff888020722500
RBP: 0000000000002004 R08: ffffffff8476a450 R09: ffffffff8df419e0
R10: dffffc0000000000 R11: ffffed10040e4487 R12: dffffc0000000000
R13: 1ffff110040e44a8 R14: ffff888020722500 R15: ffff888020722540
FS: 0000000000000000(0000) GS:ffff888125f49000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ff5e0f43000 CR3: 0000000073e76000 CR4: 00000000003526f0
Call Trace:
<TASK>
gfs2_chain_bio fs/gfs2/lops.c:487 [inline]
gfs2_find_jhead+0x627/0xe40 fs/gfs2/lops.c:549
gfs2_recover_func+0x5f5/0x1c90 fs/gfs2/recovery.c:459
process_one_work+0x93a/0x15a0 kernel/workqueue.c:3261
process_scheduled_works kernel/workqueue.c:3344 [inline]
worker_thread+0x9b0/0xee0 kernel/workqueue.c:3425
kthread+0x711/0x8a0 kernel/kthread.c:463
ret_from_fork+0x599/0xb30 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246
</TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:bio_chain+0xee/0x100 block/bio.c:342
Code: 43 1c 5b 41 5c 41 5d 41 5e 41 5f 5d e9 1b e1 f2 06 cc 89 f9 80 e1 07 fe c1 38 c1 7c cf e8 aa fc bd fd eb c8 e8 d3 a8 57 fd 90 <0f> 0b e8 cb a8 57 fd 90 0f 0b 0f 1f 84 00 00 00 00 00 90 90 90 90
RSP: 0018:ffffc90003d07540 EFLAGS: 00010293
RAX: ffffffff846a0a5d RBX: ffff8880207223c0 RCX: ffff888025b49e80
RDX: 0000000000000000 RSI: ffff8880207223c0 RDI: ffff888020722500
RBP: 0000000000002004 R08: ffffffff8476a450 R09: ffffffff8df419e0
R10: dffffc0000000000 R11: ffffed10040e4487 R12: dffffc0000000000
R13: 1ffff110040e44a8 R14: ffff888020722500 R15: ffff888020722540
FS: 0000000000000000(0000) GS:ffff888125f49000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000563e2b893950 CR3: 0000000026910000 CR4: 00000000003526f0


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