[syzbot] [jfs?] kernel BUG in txCommit (2)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 2c7c88a412aa Merge tag 'net-7.2-rc3' of git://git.kernel.o..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1271c346580000
kernel config: https://syzkaller.appspot.com/x/.config?x=98da55a882774dfe
dashboard link: https://syzkaller.appspot.com/bug?extid=af3dd9de4f75bdb1d690
compiler: Debian clang version 22.1.8 (++20260613092233+e80beda6e255-1~exp1~20260613092250.77), Debian LLD 22.1.8

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

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/29d7f7aa2ce6/disk-2c7c88a4.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/787266f15570/vmlinux-2c7c88a4.xz
kernel image: https://storage.googleapis.com/syzbot-assets/d222bd037f24/bzImage-2c7c88a4.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+af3dd9...@syzkaller.appspotmail.com

loop1: detected capacity change from 0 to 32768
------------[ cut here ]------------
kernel BUG at fs/jfs/jfs_txnmgr.c:2211!
Oops: invalid opcode: 0000 [#1] SMP KASAN PTI
CPU: 1 UID: 0 PID: 23062 Comm: syz.1.1448 Not tainted syzkaller #0 PREEMPT_{RT,(full)}
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
RIP: 0010:txForce fs/jfs/jfs_txnmgr.c:2211 [inline]
RIP: 0010:txCommit+0x544e/0x54a0 fs/jfs/jfs_txnmgr.c:1317
Code: c7 fd 90 0f 0b e8 c2 73 65 fe 48 c7 c7 e0 ee ab 8b 48 c7 c6 d9 ea ab 8b ba a3 08 00 00 48 c7 c1 40 fb ab 8b e8 43 a0 c7 fd 90 <0f> 0b e8 9b 73 65 fe 48 8b 7c 24 08 48 c7 c6 a0 fc ab 8b e8 0a ff
RSP: 0018:ffffc900043bf5e0 EFLAGS: 00010246
RAX: 000000000000003f RBX: 0000000000000000 RCX: b842d048d7fb5600
RDX: ffffc90005652000 RSI: 00000000000020bd RDI: 00000000000020be
RBP: ffffc900043bf7b0 R08: 0000000000000000 R09: 0000000000000000
R10: dffffc0000000000 R11: fffff52000877e6d R12: 0000000000000000
R13: 1ffff920006102cd R14: ffffc900033a25e8 R15: ffff888062a630b0
FS: 00007f7aa34866c0(0000) GS:ffff888125d4a000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f7aa23b7ff8 CR3: 00000000403b2000 CR4: 00000000003526f0
Call Trace:
<TASK>
duplicateIXtree+0x299/0x490 fs/jfs/jfs_imap.c:3019
diNewIAG fs/jfs/jfs_imap.c:2597 [inline]
diAllocExt fs/jfs/jfs_imap.c:1905 [inline]
diAllocAG+0x17b4/0x1de0 fs/jfs/jfs_imap.c:1669
diAlloc+0x1de/0x1690 fs/jfs/jfs_imap.c:1590
ialloc+0x8c/0x8e0 fs/jfs/jfs_inode.c:56
jfs_mkdir+0x1e4/0xb00 fs/jfs/namei.c:226
vfs_mkdir+0x402/0x620 fs/namei.c:5276
filename_mkdirat+0x289/0x520 fs/namei.c:5309
__do_sys_mkdirat fs/namei.c:5330 [inline]
__se_sys_mkdirat+0x35/0x150 fs/namei.c:5327
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f7aa522ccc7
Code: 00 66 90 48 89 f2 b9 00 01 00 00 48 89 fe bf 9c ff ff ff e9 db f7 ff ff 66 2e 0f 1f 84 00 00 00 00 00 90 b8 02 01 00 00 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:00007f7aa3485e58 EFLAGS: 00000246 ORIG_RAX: 0000000000000102
RAX: ffffffffffffffda RBX: 00007f7aa3485ee0 RCX: 00007f7aa522ccc7
RDX: 00000000000001ff RSI: 0000200000002080 RDI: 00000000ffffff9c
RBP: 0000200000002040 R08: 0000000000000000 R09: 0000000000000000
R10: 0000200000002040 R11: 0000000000000246 R12: 0000200000002080
R13: 00007f7aa3485ea0 R14: 0000000000000000 R15: 0000200000000080
</TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:txForce fs/jfs/jfs_txnmgr.c:2211 [inline]
RIP: 0010:txCommit+0x544e/0x54a0 fs/jfs/jfs_txnmgr.c:1317
Code: c7 fd 90 0f 0b e8 c2 73 65 fe 48 c7 c7 e0 ee ab 8b 48 c7 c6 d9 ea ab 8b ba a3 08 00 00 48 c7 c1 40 fb ab 8b e8 43 a0 c7 fd 90 <0f> 0b e8 9b 73 65 fe 48 8b 7c 24 08 48 c7 c6 a0 fc ab 8b e8 0a ff
RSP: 0018:ffffc900043bf5e0 EFLAGS: 00010246
RAX: 000000000000003f RBX: 0000000000000000 RCX: b842d048d7fb5600
RDX: ffffc90005652000 RSI: 00000000000020bd RDI: 00000000000020be
RBP: ffffc900043bf7b0 R08: 0000000000000000 R09: 0000000000000000
R10: dffffc0000000000 R11: fffff52000877e6d R12: 0000000000000000
R13: 1ffff920006102cd R14: ffffc900033a25e8 R15: ffff888062a630b0
FS: 00007f7aa34866c0(0000) GS:ffff888125d4a000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f7aa23b7ff8 CR3: 00000000403b2000 CR4: 00000000003526f0


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