[syzbot] [ocfs2?] general protection fault in ocfs2_evict_inode

[syzbot <syzbot+0058ba2149d0a0c61344@syzkaller.appspotmail.com>]

Hello,

syzbot found the following issue on:

HEAD commit:    33ce24234fca Add linux-next specific files for 20241008
git tree:       linux-next
console output: https://syzkaller.appspot.com/x/log.txt?x=14148f07980000
kernel config:  https://syzkaller.appspot.com/x/.config?x=4750ca93740b938d
dashboard link: https://syzkaller.appspot.com/bug?extid=0058ba2149d0a0c61344
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: https://storage.googleapis.com/syzbot-assets/ee8dc2df0c57/disk-33ce2423.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/dc473c0fa06e/vmlinux-33ce2423.xz
kernel image: https://storage.googleapis.com/syzbot-assets/4671f1ca2e61/bzImage-33ce2423.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+0058ba2149d0a0c61344@syzkaller.appspotmail.com

ocfs2: Unmounting device (7,4) on (node local)
Oops: general protection fault, probably for non-canonical address 0xdffffc0000000001: 0000 [#1] PREEMPT SMP KASAN PTI
KASAN: null-ptr-deref in range [0x0000000000000008-0x000000000000000f]
CPU: 1 UID: 0 PID: 11386 Comm: syz.4.712 Not tainted 6.12.0-rc2-next-20241008-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
RIP: 0010:ocfs2_clear_inode fs/ocfs2/inode.c:1208 [inline]
RIP: 0010:ocfs2_evict_inode+0xdd3/0x4680 fs/ocfs2/inode.c:1220
Code: 00 00 4c 89 e0 48 c1 e8 03 42 80 3c 30 00 74 08 4c 89 e7 e8 5f 17 71 fe 4c 01 f3 4d 8b 24 24 49 83 c4 08 4c 89 e0 48 c1 e8 03 <42> 80 3c 30 00 74 08 4c 89 e7 e8 3e 17 71 fe 49 8b 3c 24 49 81 c7
RSP: 0018:ffffc9000349ef00 EFLAGS: 00010202
RAX: 0000000000000001 RBX: fffff52000693df4 RCX: ffff88802db11e00
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc9000349f650 R08: ffffffff838d937e R09: 1ffff1100bf6f616
R10: dffffc0000000000 R11: ffffed100bf6f617 R12: 0000000000000008
R13: 1ffff1100bf6f644 R14: dffffc0000000000 R15: ffff88805fb7b338
FS:  0000000000000000(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000021000000 CR3: 000000002dcfc000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 evict+0x4e8/0x9b0 fs/inode.c:808
 __ocfs2_free_slot_info fs/ocfs2/slot_map.c:307 [inline]
 ocfs2_free_slot_info+0x94/0x270 fs/ocfs2/slot_map.c:443
 ocfs2_delete_osb+0x58/0x180 fs/ocfs2/super.c:2497
 ocfs2_dismount_volume+0x594/0x8f0 fs/ocfs2/super.c:1936
 generic_shutdown_super+0x139/0x2d0 fs/super.c:642
 kill_block_super+0x44/0x90 fs/super.c:1696
 deactivate_locked_super+0xc4/0x130 fs/super.c:473
 cleanup_mnt+0x41f/0x4b0 fs/namespace.c:1373
 task_work_run+0x24f/0x310 kernel/task_work.c:228
 exit_task_work include/linux/task_work.h:40 [inline]
 do_exit+0xa2f/0x28e0 kernel/exit.c:939
 do_group_exit+0x207/0x2c0 kernel/exit.c:1088
 get_signal+0x16a3/0x1740 kernel/signal.c:2917
 arch_do_signal_or_restart+0x96/0x860 arch/x86/kernel/signal.c:337
 exit_to_user_mode_loop kernel/entry/common.c:111 [inline]
 exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
 __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
 syscall_exit_to_user_mode+0xc9/0x370 kernel/entry/common.c:218
 do_syscall_64+0x100/0x230 arch/x86/entry/common.c:89
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f581257dff9
Code: Unable to access opcode bytes at 0x7f581257dfcf.
RSP: 002b:00007f5813441038 EFLAGS: 00000246 ORIG_RAX: 0000000000000000
RAX: 0000000000ffecc0 RBX: 00007f5812735f80 RCX: 00007f581257dff9
RDX: 7706c522012798af RSI: 0000000020001340 RDI: 0000000000000005
RBP: 00007f58125f0296 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f5812735f80 R15: 00007ffd87bff1c8
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:ocfs2_clear_inode fs/ocfs2/inode.c:1208 [inline]
RIP: 0010:ocfs2_evict_inode+0xdd3/0x4680 fs/ocfs2/inode.c:1220
Code: 00 00 4c 89 e0 48 c1 e8 03 42 80 3c 30 00 74 08 4c 89 e7 e8 5f 17 71 fe 4c 01 f3 4d 8b 24 24 49 83 c4 08 4c 89 e0 48 c1 e8 03 <42> 80 3c 30 00 74 08 4c 89 e7 e8 3e 17 71 fe 49 8b 3c 24 49 81 c7
RSP: 0018:ffffc9000349ef00 EFLAGS: 00010202
RAX: 0000000000000001 RBX: fffff52000693df4 RCX: ffff88802db11e00
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc9000349f650 R08: ffffffff838d937e R09: 1ffff1100bf6f616
R10: dffffc0000000000 R11: ffffed100bf6f617 R12: 0000000000000008
R13: 1ffff1100bf6f644 R14: dffffc0000000000 R15: ffff88805fb7b338
FS:  0000000000000000(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000021000000 CR3: 000000002dcfc000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess):
   0:	00 00                	add    %al,(%rax)
   2:	4c 89 e0             	mov    %r12,%rax
   5:	48 c1 e8 03          	shr    $0x3,%rax
   9:	42 80 3c 30 00       	cmpb   $0x0,(%rax,%r14,1)
   e:	74 08                	je     0x18
  10:	4c 89 e7             	mov    %r12,%rdi
  13:	e8 5f 17 71 fe       	call   0xfe711777
  18:	4c 01 f3             	add    %r14,%rbx
  1b:	4d 8b 24 24          	mov    (%r12),%r12
  1f:	49 83 c4 08          	add    $0x8,%r12
  23:	4c 89 e0             	mov    %r12,%rax
  26:	48 c1 e8 03          	shr    $0x3,%rax
* 2a:	42 80 3c 30 00       	cmpb   $0x0,(%rax,%r14,1) <-- trapping instruction
  2f:	74 08                	je     0x39
  31:	4c 89 e7             	mov    %r12,%rdi
  34:	e8 3e 17 71 fe       	call   0xfe711777
  39:	49 8b 3c 24          	mov    (%r12),%rdi
  3d:	49                   	rex.WB
  3e:	81                   	.byte 0x81
  3f:	c7                   	.byte 0xc7


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