general protection fault, probably for non-canonical address 0xdffffc00000000b2: 0000 [#1] PREEMPT SMP KASAN
KASAN: null-ptr-deref in range [0x0000000000000590-0x0000000000000597]
CPU: 0 PID: 154 Comm: kworker/u4:2 Not tainted 5.14.0-rc5-next-20210816-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: bat_events batadv_nc_worker
RIP: 0010:latency_exceeded block/blk-wbt.c:237 [inline]
RIP: 0010:wb_timer_fn+0x149/0x1740 block/blk-wbt.c:360
Code: 03 80 3c 02 00 0f 85 68 13 00 00 48 8b 9b c8 00 00 00 48 b8 00 00 00 00 00 fc ff df 48 8d bb 90 05 00 00 48 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 35 13 00 00 48 8b 9b 90 05 00 00 48 b8 00 00 00
RSP: 0018:ffffc90000007cf8 EFLAGS: 00010206
RAX: dffffc0000000000 RBX: 0000000000000000 RCX: 0000000000000100
RDX: 00000000000000b2 RSI: ffffffff83d225bd RDI: 0000000000000590
RBP: ffff88801b12f800 R08: 0000000000000003 R09: ffff88801b12f983
R10: ffffffff83d225b2 R11: 0000000000000000 R12: 0000000000000003
R13: 0000000000000000 R14: ffff88801ad72c80 R15: ffff88801b12f8d0
FS:  0000000000000000(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b31534000 CR3: 000000008d89a000 CR4: 00000000001506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 call_timer_fn+0x1a5/0x6b0 kernel/time/timer.c:1421
 expire_timers kernel/time/timer.c:1466 [inline]
 __run_timers.part.0+0x675/0xa20 kernel/time/timer.c:1734
 __run_timers kernel/time/timer.c:1715 [inline]
 run_timer_softirq+0xb3/0x1d0 kernel/time/timer.c:1747
 __do_softirq+0x29b/0x9c2 kernel/softirq.c:558
 do_softirq.part.0+0xde/0x130 kernel/softirq.c:459
 </IRQ>
 do_softirq kernel/softirq.c:451 [inline]
 __local_bh_enable_ip+0x102/0x120 kernel/softirq.c:383
 spin_unlock_bh include/linux/spinlock.h:404 [inline]
 batadv_nc_purge_paths+0x2a5/0x3a0 net/batman-adv/network-coding.c:467
 batadv_nc_worker+0x7ff/0xe50 net/batman-adv/network-coding.c:716
 process_one_work+0x98d/0x1630 kernel/workqueue.c:2275
 worker_thread+0x658/0x11f0 kernel/workqueue.c:2421
 kthread+0x3e5/0x4d0 kernel/kthread.c:319
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
Modules linked in:
---[ end trace bfa44350a3664bda ]---
RIP: 0010:latency_exceeded block/blk-wbt.c:237 [inline]
RIP: 0010:wb_timer_fn+0x149/0x1740 block/blk-wbt.c:360
Code: 03 80 3c 02 00 0f 85 68 13 00 00 48 8b 9b c8 00 00 00 48 b8 00 00 00 00 00 fc ff df 48 8d bb 90 05 00 00 48 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 35 13 00 00 48 8b 9b 90 05 00 00 48 b8 00 00 00
RSP: 0018:ffffc90000007cf8 EFLAGS: 00010206
RAX: dffffc0000000000 RBX: 0000000000000000 RCX: 0000000000000100
RDX: 00000000000000b2 RSI: ffffffff83d225bd RDI: 0000000000000590
RBP: ffff88801b12f800 R08: 0000000000000003 R09: ffff88801b12f983
R10: ffffffff83d225b2 R11: 0000000000000000 R12: 0000000000000003
R13: 0000000000000000 R14: ffff88801ad72c80 R15: ffff88801b12f8d0
FS:  0000000000000000(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b31534000 CR3: 000000008d89a000 CR4: 00000000001506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess):
   0:	03 80 3c 02 00 0f    	add    0xf00023c(%rax),%eax
   6:	85 68 13             	test   %ebp,0x13(%rax)
   9:	00 00                	add    %al,(%rax)
   b:	48 8b 9b c8 00 00 00 	mov    0xc8(%rbx),%rbx
  12:	48 b8 00 00 00 00 00 	movabs $0xdffffc0000000000,%rax
  19:	fc ff df 
  1c:	48 8d bb 90 05 00 00 	lea    0x590(%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 35 13 00 00    	jne    0x1369
  34:	48 8b 9b 90 05 00 00 	mov    0x590(%rbx),%rbx
  3b:	48                   	rex.W
  3c:	b8                   	.byte 0xb8
  3d:	00 00                	add    %al,(%rax)