linux-kernel - [syzbot] [ocfs2?] general protection fault in ocfs2_clear

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Message-ID: <688795bf.050a0220.3cc461.000c.GAE@google.com>
Date: Mon, 28 Jul 2025 08:22:39 -0700
From: syzbot <syzbot+d58fc9c4a90032ed31ff@...kaller.appspotmail.com>
To: jlbec@...lplan.org, joseph.qi@...ux.alibaba.com, 
	linux-kernel@...r.kernel.org, mark@...heh.com, ocfs2-devel@...ts.linux.dev, 
	syzkaller-bugs@...glegroups.com
Subject: [syzbot] [ocfs2?] general protection fault in ocfs2_clear_inode (2)

Hello,

syzbot found the following issue on:

HEAD commit:    038d61fd6422 Linux 6.16
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=16941034580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=be3042dc81e96425
dashboard link: https://syzkaller.appspot.com/bug?extid=d58fc9c4a90032ed31ff
compiler:       gcc (Debian 12.2.0-14+deb12u1) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40

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

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/96c326de2cf2/disk-038d61fd.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/cf0010801745/vmlinux-038d61fd.xz
kernel image: https://storage.googleapis.com/syzbot-assets/572bd02ef3c3/bzImage-038d61fd.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+d58fc9c4a90032ed31ff@...kaller.appspotmail.com

 </TASK>
ocfs2: Unmounting device (7,5) on (node local)
Oops: general protection fault, probably for non-canonical address 0xdffffc0000000001: 0000 [#1] SMP KASAN NOPTI
KASAN: null-ptr-deref in range [0x0000000000000008-0x000000000000000f]
CPU: 1 UID: 0 PID: 21048 Comm: syz-executor Not tainted 6.16.0-syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
RIP: 0010:ocfs2_clear_inode+0x56e/0x1540 fs/ocfs2/inode.c:1222
Code: 48 c1 ea 03 80 3c 02 00 0f 85 c0 08 00 00 48 8b 9d 90 02 00 00 48 b8 00 00 00 00 00 fc ff df 48 8d 7b 08 48 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 88 08 00 00 48 8b 7b 08 e8 9f 3f e4 fe 48 8b 4c
RSP: 0018:ffffc90004c97898 EFLAGS: 00010212
RAX: dffffc0000000000 RBX: 0000000000000000 RCX: ffffffff83a9864b
RDX: 0000000000000001 RSI: ffff888050de37c0 RDI: 0000000000000008
RBP: ffff8880581cc000 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000001 R12: ffff888050de2ac0
R13: ffff888050de3220 R14: ffff888050de32d0 R15: 0000000000000000
FS:  000055558ade6500(0000) GS:ffff888124827000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f5659596e9c CR3: 00000000575b2000 CR4: 0000000000350ef0
Call Trace:
 <TASK>
 ocfs2_evict_inode+0x8fb/0x1680 fs/ocfs2/inode.c:1234
 evict+0x3e6/0x920 fs/inode.c:810
 iput_final fs/inode.c:1898 [inline]
 iput fs/inode.c:1924 [inline]
 iput+0x521/0x880 fs/inode.c:1910
 __ocfs2_free_slot_info.part.0+0x3e/0x210 fs/ocfs2/slot_map.c:307
 __ocfs2_free_slot_info fs/ocfs2/slot_map.c:304 [inline]
 ocfs2_free_slot_info+0x47/0x60 fs/ocfs2/slot_map.c:443
 ocfs2_delete_osb+0x52/0x1f0 fs/ocfs2/super.c:2450
 ocfs2_dismount_volume+0x445/0xa00 fs/ocfs2/super.c:1884
 generic_shutdown_super+0x156/0x390 fs/super.c:643
 kill_block_super+0x3b/0x90 fs/super.c:1755
 deactivate_locked_super+0xc1/0x1a0 fs/super.c:474
 deactivate_super fs/super.c:507 [inline]
 deactivate_super+0xde/0x100 fs/super.c:503
 cleanup_mnt+0x225/0x450 fs/namespace.c:1417
 task_work_run+0x150/0x240 kernel/task_work.c:227
 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
 exit_to_user_mode_loop+0xeb/0x110 kernel/entry/common.c:114
 exit_to_user_mode_prepare include/linux/entry-common.h:330 [inline]
 syscall_exit_to_user_mode_work include/linux/entry-common.h:414 [inline]
 syscall_exit_to_user_mode include/linux/entry-common.h:449 [inline]
 do_syscall_64+0x3f6/0x4c0 arch/x86/entry/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f0ecef8fcd7
Code: a8 ff ff ff f7 d8 64 89 01 48 83 c8 ff c3 0f 1f 44 00 00 31 f6 e9 09 00 00 00 66 0f 1f 84 00 00 00 00 00 b8 a6 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 01 c3 48 c7 c2 a8 ff ff ff f7 d8 64 89 02 b8
RSP: 002b:00007fff28c54848 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 00007f0ecf010b55 RCX: 00007f0ecef8fcd7
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007fff28c54900
RBP: 00007fff28c54900 R08: 0000000000000000 R09: 0000000000000000
R10: 00000000ffffffff R11: 0000000000000246 R12: 00007fff28c55990
R13: 00007f0ecf010b55 R14: 00000000001604be R15: 00007fff28c559d0
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:ocfs2_clear_inode+0x56e/0x1540 fs/ocfs2/inode.c:1222
Code: 48 c1 ea 03 80 3c 02 00 0f 85 c0 08 00 00 48 8b 9d 90 02 00 00 48 b8 00 00 00 00 00 fc ff df 48 8d 7b 08 48 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 88 08 00 00 48 8b 7b 08 e8 9f 3f e4 fe 48 8b 4c
RSP: 0018:ffffc90004c97898 EFLAGS: 00010212
RAX: dffffc0000000000 RBX: 0000000000000000 RCX: ffffffff83a9864b
RDX: 0000000000000001 RSI: ffff888050de37c0 RDI: 0000000000000008
RBP: ffff8880581cc000 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000001 R12: ffff888050de2ac0
R13: ffff888050de3220 R14: ffff888050de32d0 R15: 0000000000000000
FS:  000055558ade6500(0000) GS:ffff888124727000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055d77c2d24b0 CR3: 00000000575b2000 CR4: 0000000000350ef0
----------------
Code disassembly (best guess):
   0:	48 c1 ea 03          	shr    $0x3,%rdx
   4:	80 3c 02 00          	cmpb   $0x0,(%rdx,%rax,1)
   8:	0f 85 c0 08 00 00    	jne    0x8ce
   e:	48 8b 9d 90 02 00 00 	mov    0x290(%rbp),%rbx
  15:	48 b8 00 00 00 00 00 	movabs $0xdffffc0000000000,%rax
  1c:	fc ff df
  1f:	48 8d 7b 08          	lea    0x8(%rbx),%rdi
  23:	48 89 fa             	mov    %rdi,%rdx
  26:	48 c1 ea 03          	shr    $0x3,%rdx
* 2a:	80 3c 02 00          	cmpb   $0x0,(%rdx,%rax,1) <-- trapping instruction
  2e:	0f 85 88 08 00 00    	jne    0x8bc
  34:	48 8b 7b 08          	mov    0x8(%rbx),%rdi
  38:	e8 9f 3f e4 fe       	call   0xfee43fdc
  3d:	48                   	rex.W
  3e:	8b                   	.byte 0x8b
  3f:	4c                   	rex.WR


---
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