[syzbot] [ocfs2?] kernel BUG in ocfs2_remove_extent

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

Hello,

syzbot found the following issue on:

HEAD commit:    c89756bcf406 Merge tag 'pm-6.16-rc1' of git://git.kernel.o..
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=15fae6d4580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=ded97a85afe9a6c8
dashboard link: https://syzkaller.appspot.com/bug?extid=8882b2f5f48a7170a726
compiler:       Debian clang version 20.1.6 (++20250514063057+1e4d39e07757-1~exp1~20250514183223.118), Debian LLD 20.1.6

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

Downloadable assets:
disk image (non-bootable): https://storage.googleapis.com/syzbot-assets/d900f083ada3/non_bootable_disk-c89756bc.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/b21d74e73303/vmlinux-c89756bc.xz
kernel image: https://storage.googleapis.com/syzbot-assets/b778ededeb75/bzImage-c89756bc.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+8882b2f5f48a7170a726@syzkaller.appspotmail.com

------------[ cut here ]------------
kernel BUG at fs/ocfs2/alloc.c:5581!
Oops: invalid opcode: 0000 [#1] SMP KASAN NOPTI
CPU: 0 UID: 0 PID: 5320 Comm: syz.0.0 Not tainted 6.15.0-syzkaller-03478-gc89756bcf406 #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+0x1ecf/0x2020 fs/ocfs2/alloc.c:5581
Code: fa ff ff 48 8b 4c 24 08 80 e1 07 fe c1 38 c1 0f 8c 95 fa ff ff 48 8b 7c 24 08 e8 4c e8 8f fe e9 86 fa ff ff e8 22 08 2d fe 90 <0f> 0b f3 0f 1e fa 44 89 6c 24 10 65 8b 1d f3 25 06 0f bf 07 00 00
RSP: 0018:ffffc9000d3ee980 EFLAGS: 00010287
RAX: ffffffff8392ea2e RBX: ffffc9000d3ef178 RCX: 0000000000100000
RDX: ffffc9000ee94000 RSI: 000000000004f2da RDI: 000000000004f2db
RBP: ffffc9000d3eecd0 R08: ffff88803c8c4880 R09: 0000000000000006
R10: 00000000fffffffc R11: 0000000000000002 R12: 1ffff1100abcf048
R13: 0000000000000007 R14: ffff888055e78240 R15: dffffc0000000000
FS:  00007f98ae9896c0(0000) GS:ffff88808d28f000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fb0dc3a17e0 CR3: 000000003e12a000 CR4: 0000000000352ef0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 ocfs2_remove_btree_range+0xdef/0x1540 fs/ocfs2/alloc.c:5778
 ocfs2_commit_truncate+0xb64/0x21d0 fs/ocfs2/alloc.c:7373
 ocfs2_truncate_file+0xca2/0x1420 fs/ocfs2/file.c:509
 ocfs2_setattr+0x1520/0x1b40 fs/ocfs2/file.c:1212
 notify_change+0xb33/0xe40 fs/attr.c:552
 do_truncate+0x1a4/0x220 fs/open.c:68
 handle_truncate fs/namei.c:3508 [inline]
 do_open fs/namei.c:3891 [inline]
 path_openat+0x306c/0x3830 fs/namei.c:4046
 do_filp_open+0x1fa/0x410 fs/namei.c:4073
 do_sys_openat2+0x121/0x1c0 fs/open.c:1437
 do_sys_open fs/open.c:1452 [inline]
 __do_sys_creat fs/open.c:1530 [inline]
 __se_sys_creat fs/open.c:1524 [inline]
 __x64_sys_creat+0x8f/0xc0 fs/open.c:1524
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f98adb8e969
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f98ae989038 EFLAGS: 00000246 ORIG_RAX: 0000000000000055
RAX: ffffffffffffffda RBX: 00007f98addb6160 RCX: 00007f98adb8e969
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000200000000040
RBP: 00007f98adc10ab1 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f98addb6160 R15: 00007ffd2df48568
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:ocfs2_remove_extent+0x1ecf/0x2020 fs/ocfs2/alloc.c:5581
Code: fa ff ff 48 8b 4c 24 08 80 e1 07 fe c1 38 c1 0f 8c 95 fa ff ff 48 8b 7c 24 08 e8 4c e8 8f fe e9 86 fa ff ff e8 22 08 2d fe 90 <0f> 0b f3 0f 1e fa 44 89 6c 24 10 65 8b 1d f3 25 06 0f bf 07 00 00
RSP: 0018:ffffc9000d3ee980 EFLAGS: 00010287
RAX: ffffffff8392ea2e RBX: ffffc9000d3ef178 RCX: 0000000000100000
RDX: ffffc9000ee94000 RSI: 000000000004f2da RDI: 000000000004f2db
RBP: ffffc9000d3eecd0 R08: ffff88803c8c4880 R09: 0000000000000006
R10: 00000000fffffffc R11: 0000000000000002 R12: 1ffff1100abcf048
R13: 0000000000000007 R14: ffff888055e78240 R15: dffffc0000000000
FS:  00007f98ae9896c0(0000) GS:ffff88808d28f000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffcc92d0d90 CR3: 000000003e12a000 CR4: 0000000000352ef0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400


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