[syzbot] [ocfs2?] kernel BUG in ocfs2_clear_cow_buffer

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit:    1d227fcc7222 Merge tag 'net-6.12-rc3' of git://git.kernel...
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=104f9fd0580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=7cd9e7e4a8a0a15b
dashboard link: https://syzkaller.appspot.com/bug?extid=69c3bc471900052ecff5
compiler:       Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40

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

Downloadable assets:
disk image (non-bootable): https://storage.googleapis.com/syzbot-assets/7feb34a89c2a/non_bootable_disk-1d227fcc.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/ea82465646ea/vmlinux-1d227fcc.xz
kernel image: https://storage.googleapis.com/syzbot-assets/f764dd6d008a/bzImage-1d227fcc.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+69c3bc471900052ecff5@xxxxxxxxxxxxxxxxxxxxxxxxx

------------[ cut here ]------------
kernel BUG at fs/ocfs2/refcounttree.c:2890!
Oops: invalid opcode: 0000 [#1] PREEMPT SMP KASAN NOPTI
CPU: 0 UID: 0 PID: 5114 Comm: syz.0.0 Not tainted 6.12.0-rc2-syzkaller-00205-g1d227fcc7222 #0
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_clear_cow_buffer+0x79/0x80 fs/ocfs2/refcounttree.c:2890
Code: 02 75 21 e8 09 e3 02 fe 4c 89 f7 be 08 00 00 00 e8 1c 96 6c fe 3e 41 80 26 ef 31 c0 5b 41 5e c3 cc cc cc cc e8 e8 e2 02 fe 90 <0f> 0b 0f 1f 44 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90
RSP: 0018:ffffc9000179ebe0 EFLAGS: 00010283
RAX: ffffffff83920468 RBX: 0000000000000002 RCX: 0000000000040000
RDX: ffffc9000b912000 RSI: 0000000000008db5 RDI: 0000000000008db6
RBP: 0000000000001000 R08: ffffffff8392043c R09: 1ffff110039a821d
R10: dffffc0000000000 R11: ffffed10039a821e R12: ffff88801cd410e8
R13: ffff88801cd41000 R14: ffff88801cd410e8 R15: 0000000000000000
FS:  00007ff66de346c0(0000) GS:ffff88801fc00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ff66de12f98 CR3: 000000004b480000 CR4: 0000000000352ef0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 walk_page_buffers+0x104/0x1d0 fs/ocfs2/aops.c:434
 ocfs2_duplicate_clusters_by_page+0xb0a/0x1450 fs/ocfs2/refcounttree.c:2970
 ocfs2_replace_clusters fs/ocfs2/refcounttree.c:3123 [inline]
 ocfs2_make_clusters_writable fs/ocfs2/refcounttree.c:3255 [inline]
 ocfs2_replace_cow+0xd82/0x25d0 fs/ocfs2/refcounttree.c:3349
 ocfs2_refcount_cow_hunk fs/ocfs2/refcounttree.c:3427 [inline]
 ocfs2_refcount_cow+0x9c9/0x11c0 fs/ocfs2/refcounttree.c:3470
 ocfs2_prepare_inode_for_write fs/ocfs2/file.c:2329 [inline]
 ocfs2_file_write_iter+0xf34/0x1f50 fs/ocfs2/file.c:2438
 iter_file_splice_write+0xbfa/0x1510 fs/splice.c:743
 do_splice_from fs/splice.c:941 [inline]
 direct_splice_actor+0x11b/0x220 fs/splice.c:1164
 splice_direct_to_actor+0x586/0xc80 fs/splice.c:1108
 do_splice_direct_actor fs/splice.c:1207 [inline]
 do_splice_direct+0x289/0x3e0 fs/splice.c:1233
 do_sendfile+0x561/0xe10 fs/read_write.c:1388
 __do_sys_sendfile64 fs/read_write.c:1455 [inline]
 __se_sys_sendfile64+0x17c/0x1e0 fs/read_write.c:1441
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7ff66cf7dff9
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:00007ff66de34038 EFLAGS: 00000246 ORIG_RAX: 0000000000000028
RAX: ffffffffffffffda RBX: 00007ff66d136058 RCX: 00007ff66cf7dff9
RDX: 0000000000000000 RSI: 0000000000000004 RDI: 0000000000000004
RBP: 00007ff66cff0296 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000800000009 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007ff66d136058 R15: 00007ffd4e93c2d8
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:ocfs2_clear_cow_buffer+0x79/0x80 fs/ocfs2/refcounttree.c:2890
Code: 02 75 21 e8 09 e3 02 fe 4c 89 f7 be 08 00 00 00 e8 1c 96 6c fe 3e 41 80 26 ef 31 c0 5b 41 5e c3 cc cc cc cc e8 e8 e2 02 fe 90 <0f> 0b 0f 1f 44 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90
RSP: 0018:ffffc9000179ebe0 EFLAGS: 00010283
RAX: ffffffff83920468 RBX: 0000000000000002 RCX: 0000000000040000
RDX: ffffc9000b912000 RSI: 0000000000008db5 RDI: 0000000000008db6
RBP: 0000000000001000 R08: ffffffff8392043c R09: 1ffff110039a821d
R10: dffffc0000000000 R11: ffffed10039a821e R12: ffff88801cd410e8
R13: ffff88801cd41000 R14: ffff88801cd410e8 R15: 0000000000000000
FS:  00007ff66de346c0(0000) GS:ffff88801fc00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000056023ce6a038 CR3: 000000004b480000 CR4: 0000000000352ef0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400


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