Re: [syzbot] [ocfs2?] kernel BUG in ocfs2_remove_extent

[syzbot <syzbot+8882b2f5f48a7170a726@syzkaller.appspotmail.com>]

Hello,

syzbot has tested the proposed patch but the reproducer is still triggering an issue:
kernel BUG in ocfs2_remove_extent

------------[ cut here ]------------
kernel BUG at fs/ocfs2/alloc.c:5581!
Oops: invalid opcode: 0000 [#1] SMP KASAN NOPTI
CPU: 0 UID: 0 PID: 5971 Comm: syz.0.17 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
RIP: 0010:ocfs2_remove_extent+0x2050/0x21a0 fs/ocfs2/alloc.c:5581
Code: f9 ff ff 48 8b 4c 24 08 80 e1 07 fe c1 38 c1 0f 8c 27 fa ff ff 48 8b 7c 24 08 e8 db 38 8a fe e9 18 fa ff ff e8 61 fa 22 fe 90 <0f> 0b f3 0f 1e fa 65 44 8b 3d 06 58 cf 0e bf 07 00 00 00 44 89 fe
RSP: 0018:ffffc90002a5e620 EFLAGS: 00010293
RAX: ffffffff839cb81f RBX: 0000000000000007 RCX: ffff888035d2a480
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000007
RBP: ffffc90002a5e970 R08: ffff888035d2a480 R09: 0000000000000006
R10: 00000000fffffffc R11: 0000000000000000 R12: 0000000000000000
R13: dffffc0000000000 R14: 0000000000000000 R15: 0000000000000001
FS:  0000000000000000(0000) GS:ffff88808d75f000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fe0a8a6eb4c CR3: 0000000042743000 CR4: 0000000000352ef0
Call Trace:
 <TASK>
 ocfs2_remove_btree_range+0xdef/0x1540 fs/ocfs2/alloc.c:5778
 ocfs2_commit_truncate+0xba7/0x2250 fs/ocfs2/alloc.c:7373
 ocfs2_truncate_for_delete fs/ocfs2/inode.c:699 [inline]
 ocfs2_wipe_inode fs/ocfs2/inode.c:866 [inline]
 ocfs2_delete_inode fs/ocfs2/inode.c:1155 [inline]
 ocfs2_evict_inode+0x1138/0x4100 fs/ocfs2/inode.c:1295
 evict+0x504/0x9c0 fs/inode.c:810
 ocfs2_dentry_iput+0x247/0x370 fs/ocfs2/dcache.c:407
 __dentry_kill+0x209/0x660 fs/dcache.c:669
 dput+0x19f/0x2b0 fs/dcache.c:911
 __fput+0x68e/0xa70 fs/file_table.c:476
 task_work_run+0x1d4/0x260 kernel/task_work.c:227
 exit_task_work include/linux/task_work.h:40 [inline]
 do_exit+0x6b5/0x2300 kernel/exit.c:966
 do_group_exit+0x21c/0x2d0 kernel/exit.c:1107
 get_signal+0x1285/0x1340 kernel/signal.c:3034
 arch_do_signal_or_restart+0xa0/0x790 arch/x86/kernel/signal.c:337
 exit_to_user_mode_loop kernel/entry/common.c:40 [inline]
 exit_to_user_mode_prepare include/linux/irq-entry-common.h:225 [inline]
 irqentry_exit_to_user_mode+0x7e/0x110 kernel/entry/common.c:73
 exc_page_fault+0xab/0x100 arch/x86/mm/fault.c:1535
 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:618
RIP: 0033:0x7f95a3d8ebf1
Code: Unable to access opcode bytes at 0x7f95a3d8ebc7.
RSP: 002b:00000000fffffeb0 EFLAGS: 00010217
RAX: 0000000000000000 RBX: 00007f95a3fb5fa0 RCX: 00007f95a3d8ebe9
RDX: 0000000000000000 RSI: 00000000fffffeb0 RDI: 0000000002000400
RBP: 00007f95a3e11e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000
R13: 00007f95a3fb6038 R14: 00007f95a3fb5fa0 R15: 00007ffc4e081d38
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:ocfs2_remove_extent+0x2050/0x21a0 fs/ocfs2/alloc.c:5581
Code: f9 ff ff 48 8b 4c 24 08 80 e1 07 fe c1 38 c1 0f 8c 27 fa ff ff 48 8b 7c 24 08 e8 db 38 8a fe e9 18 fa ff ff e8 61 fa 22 fe 90 <0f> 0b f3 0f 1e fa 65 44 8b 3d 06 58 cf 0e bf 07 00 00 00 44 89 fe
RSP: 0018:ffffc90002a5e620 EFLAGS: 00010293
RAX: ffffffff839cb81f RBX: 0000000000000007 RCX: ffff888035d2a480
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000007
RBP: ffffc90002a5e970 R08: ffff888035d2a480 R09: 0000000000000006
R10: 00000000fffffffc R11: 0000000000000000 R12: 0000000000000000
R13: dffffc0000000000 R14: 0000000000000000 R15: 0000000000000001
FS:  0000000000000000(0000) GS:ffff88808d75f000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f37f9a6d000 CR3: 000000003623c000 CR4: 0000000000352ef0


Tested on:

commit:         552c5071 Merge tag 'vfio-v6.18-rc3' of https://github...
git tree:       https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
console output: https://syzkaller.appspot.com/x/log.txt?x=16099b04580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=cb89820a01e5d251
dashboard link: https://syzkaller.appspot.com/bug?extid=8882b2f5f48a7170a726
compiler:       Debian clang version 20.1.8 (++20250708063551+0c9f909b7976-1~exp1~20250708183702.136), Debian LLD 20.1.8
patch:          https://syzkaller.appspot.com/x/patch.diff?x=1116ce7c580000