[moderation] [jfs?] stack segment fault in release_metapage

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 2b38afce25c4 Merge tag 'turbostat-2025.09.09' of git://git..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=14a1b434580000
kernel config: https://syzkaller.appspot.com/x/.config?x=251464a47fe663c3
dashboard link: https://syzkaller.appspot.com/bug?extid=930e78f84311896ea6e8
compiler: Debian clang version 20.1.7 (++20250616065708+6146a88f6049-1~exp1~20250616065826.132), Debian LLD 20.1.7
CC: [jfs-dis...@lists.sourceforge.net linux-...@vger.kernel.org sha...@kernel.org]

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

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/672ffc715957/disk-2b38afce.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/21a002b17152/vmlinux-2b38afce.xz
kernel image: https://storage.googleapis.com/syzbot-assets/e085576a0201/bzImage-2b38afce.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+930e78...@syzkaller.appspotmail.com

Oops: stack segment: 0000 [#1] SMP KASAN PTI
CPU: 1 UID: 0 PID: 121 Comm: jfsCommit Tainted: G W 6.16.0-syzkaller-12288-g2b38afce25c4 #0 PREEMPT_{RT,(full)}
Tainted: [W]=WARN
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
RIP: 0010:folio_flags include/linux/page-flags.h:360 [inline]
RIP: 0010:folio_trylock include/linux/pagemap.h:1096 [inline]
RIP: 0010:folio_lock include/linux/pagemap.h:1132 [inline]
RIP: 0010:release_metapage+0x9e/0xab0 fs/jfs/jfs_metapage.c:870
Code: 04 00 00 e8 54 d4 87 fe 48 c7 c7 ab ee 05 8d be 6b 04 00 00 e8 c3 c4 5a fe 2e 2e 2e 31 c0 49 8d 5c 24 08 48 89 dd 48 c1 ed 03 <42> 80 7c 2d 00 00 74 08 48 89 df e8 e2 0b e7 fe 4c 8b 3b 4c 89 fe
RSP: 0018:ffffc900039e76d8 EFLAGS: 00010202
RAX: 0000000000000000 RBX: 0000000000000008 RCX: 87fd5932402a4100
RDX: ffff88801e3f0000 RSI: ffffffff8d21768a RDI: ffffffff8b620a00
RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000000
R10: dffffc0000000000 R11: ffffed100bc28c56 R12: 0000000000000000
R13: dffffc0000000000 R14: ffff88805e146288 R15: dffffc0000000000
FS: 0000000000000000(0000) GS:ffff8881269c5000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f7e68b21a10 CR3: 0000000021314000 CR4: 00000000003526f0
Call Trace:
<TASK>
xtTruncate+0xe84/0x2e70 fs/jfs/jfs_xtree.c:-1
jfs_free_zero_link+0x33a/0x4a0 fs/jfs/namei.c:759
jfs_evict_inode+0x363/0x440 fs/jfs/inode.c:153
evict+0x504/0x9c0 fs/inode.c:810
txLazyCommit fs/jfs/jfs_txnmgr.c:2664 [inline]
jfs_lazycommit+0x3f1/0xa10 fs/jfs/jfs_txnmgr.c:2733
kthread+0x711/0x8a0 kernel/kthread.c:463
ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
</TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:folio_flags include/linux/page-flags.h:360 [inline]
RIP: 0010:folio_trylock include/linux/pagemap.h:1096 [inline]
RIP: 0010:folio_lock include/linux/pagemap.h:1132 [inline]
RIP: 0010:release_metapage+0x9e/0xab0 fs/jfs/jfs_metapage.c:870
Code: 04 00 00 e8 54 d4 87 fe 48 c7 c7 ab ee 05 8d be 6b 04 00 00 e8 c3 c4 5a fe 2e 2e 2e 31 c0 49 8d 5c 24 08 48 89 dd 48 c1 ed 03 <42> 80 7c 2d 00 00 74 08 48 89 df e8 e2 0b e7 fe 4c 8b 3b 4c 89 fe
RSP: 0018:ffffc900039e76d8 EFLAGS: 00010202
RAX: 0000000000000000 RBX: 0000000000000008 RCX: 87fd5932402a4100
RDX: ffff88801e3f0000 RSI: ffffffff8d21768a RDI: ffffffff8b620a00
RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000000
R10: dffffc0000000000 R11: ffffed100bc28c56 R12: 0000000000000000
R13: dffffc0000000000 R14: ffff88805e146288 R15: dffffc0000000000
FS: 0000000000000000(0000) GS:ffff8881269c5000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f7e68b21a10 CR3: 0000000021314000 CR4: 00000000003526f0
----------------
Code disassembly (best guess), 1 bytes skipped:
0: 00 00 add %al,(%rax)
2: e8 54 d4 87 fe call 0xfe87d45b
7: 48 c7 c7 ab ee 05 8d mov $0xffffffff8d05eeab,%rdi
e: be 6b 04 00 00 mov $0x46b,%esi
13: e8 c3 c4 5a fe call 0xfe5ac4db
18: 2e 2e 2e 31 c0 cs cs cs xor %eax,%eax
1d: 49 8d 5c 24 08 lea 0x8(%r12),%rbx
22: 48 89 dd mov %rbx,%rbp
25: 48 c1 ed 03 shr $0x3,%rbp
* 29: 42 80 7c 2d 00 00 cmpb $0x0,0x0(%rbp,%r13,1) <-- trapping instruction
2f: 74 08 je 0x39
31: 48 89 df mov %rbx,%rdi
34: e8 e2 0b e7 fe call 0xfee70c1b
39: 4c 8b 3b mov (%rbx),%r15
3c: 4c 89 fe mov %r15,%rsi


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