syzbot

Oops: general protection fault, probably for non-canonical address 0xdffffc0000000011: 0000 [#1] SMP KASAN NOPTI
KASAN: null-ptr-deref in range [0x0000000000000088-0x000000000000008f]
CPU: 1 UID: 0 PID: 2099 Comm: kworker/1:1H Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
Workqueue: gfs2-glock/syz:syz glock_work_func
RIP: 0010:__gfs2_trans_begin+0x3b2/0xbc0 fs/gfs2/trans.c:73
Code: 80 3c 02 00 0f 85 21 07 00 00 4c 8b a5 f0 09 00 00 48 b8 00 00 00 00 00 fc ff df 49 8d bc 24 8c 00 00 00 48 89 fa 48 c1 ea 03 <0f> b6 14 02 48 89 f8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 ba
RSP: 0018:ffffc90006fb7930 EFLAGS: 00010217
RAX: dffffc0000000000 RBX: ffffc90006fb7a18 RCX: ffffffff846974c8
RDX: 0000000000000011 RSI: ffffffff846974d6 RDI: 000000000000008c
RBP: ffff88807b744000 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: ffff88807b7440a8 R14: 1ffff92000df6f2a R15: 0000000000000004
FS:  0000000000000000(0000) GS:ffff88812444a000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000002000 CR3: 000000005fd62000 CR4: 0000000000350ef0
Call Trace:
 <TASK>
 gfs2_ail_empty_gl+0x239/0x2d0 fs/gfs2/glops.c:125
 inode_go_sync+0x21d/0x5a0 fs/gfs2/glops.c:332
 do_xmote+0x1da/0x680 fs/gfs2/glock.c:688
 run_queue+0x555/0x6a0 fs/gfs2/glock.c:784
 glock_work_func+0x127/0x4d0 fs/gfs2/glock.c:1011
 process_one_work+0x9d7/0x1920 kernel/workqueue.c:3275
 process_scheduled_works kernel/workqueue.c:3358 [inline]
 worker_thread+0x5da/0xe40 kernel/workqueue.c:3439
 kthread+0x370/0x450 kernel/kthread.c:467
 ret_from_fork+0x754/0xd80 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:__gfs2_trans_begin+0x3b2/0xbc0 fs/gfs2/trans.c:73
Code: 80 3c 02 00 0f 85 21 07 00 00 4c 8b a5 f0 09 00 00 48 b8 00 00 00 00 00 fc ff df 49 8d bc 24 8c 00 00 00 48 89 fa 48 c1 ea 03 <0f> b6 14 02 48 89 f8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 ba
RSP: 0018:ffffc90006fb7930 EFLAGS: 00010217
RAX: dffffc0000000000 RBX: ffffc90006fb7a18 RCX: ffffffff846974c8
RDX: 0000000000000011 RSI: ffffffff846974d6 RDI: 000000000000008c
RBP: ffff88807b744000 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: ffff88807b7440a8 R14: 1ffff92000df6f2a R15: 0000000000000004
FS:  0000000000000000(0000) GS:ffff88812444a000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000003000 CR3: 000000005fd62000 CR4: 0000000000350ef0
----------------
Code disassembly (best guess):
   0:	80 3c 02 00          	cmpb   $0x0,(%rdx,%rax,1)
   4:	0f 85 21 07 00 00    	jne    0x72b
   a:	4c 8b a5 f0 09 00 00 	mov    0x9f0(%rbp),%r12
  11:	48 b8 00 00 00 00 00 	movabs $0xdffffc0000000000,%rax
  18:	fc ff df
  1b:	49 8d bc 24 8c 00 00 	lea    0x8c(%r12),%rdi
  22:	00
  23:	48 89 fa             	mov    %rdi,%rdx
  26:	48 c1 ea 03          	shr    $0x3,%rdx
* 2a:	0f b6 14 02          	movzbl (%rdx,%rax,1),%edx <-- trapping instruction
  2e:	48 89 f8             	mov    %rdi,%rax
  31:	83 e0 07             	and    $0x7,%eax
  34:	83 c0 03             	add    $0x3,%eax
  37:	38 d0                	cmp    %dl,%al
  39:	7c 08                	jl     0x43
  3b:	84 d2                	test   %dl,%dl
  3d:	0f                   	.byte 0xf
  3e:	85                   	.byte 0x85
  3f:	ba                   	.byte 0xba