BUG: kernel NULL pointer dereference, address: 0000000000000000
#PF: supervisor instruction fetch in kernel mode
#PF: error_code(0x0010) - not-present page
PGD 4e2a6067 P4D 4e2a6067 PUD 79002067 PMD 0 
Oops: 0010 [#1] PREEMPT SMP KASAN
CPU: 0 PID: 10683 Comm: kworker/u4:8 Not tainted 5.18.0-rc7-syzkaller-00131-g8c3b8dc5cc9b #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: bat_events batadv_nc_worker
RIP: 0010:0x0
Code: Unable to access opcode bytes at RIP 0xffffffffffffffd6.
RSP: 0018:ffffc90000007a60 EFLAGS: 00010246
RAX: dffffc0000000000 RBX: ffff88807d6bab50 RCX: 0000000000000100
RDX: 1ffff1100fad756b RSI: ffff888047abc000 RDI: ffff888045febc00
RBP: ffff888045febc00 R08: 0000000000000000 R09: 0000000000000000
R10: ffffffff87d5df57 R11: 0000000000000000 R12: ffff888047abc000
R13: 0000000000000000 R14: ffff888045fec360 R15: ffff88801e1a492c
FS:  0000000000000000(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffffffffffffd6 CR3: 000000004e361000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 __tcp_transmit_skb+0x1098/0x38b0 net/ipv4/tcp_output.c:1372
 tcp_transmit_skb net/ipv4/tcp_output.c:1421 [inline]
 tcp_xmit_probe_skb+0x28c/0x320 net/ipv4/tcp_output.c:4010
 tcp_write_wakeup+0x1bd/0x610 net/ipv4/tcp_output.c:4063
 tcp_send_probe0+0x44/0x560 net/ipv4/tcp_output.c:4078
 tcp_probe_timer net/ipv4/tcp_timer.c:398 [inline]
 tcp_write_timer_handler+0x9ed/0xbc0 net/ipv4/tcp_timer.c:626
 tcp_write_timer+0xa2/0x2b0 net/ipv4/tcp_timer.c:642
 call_timer_fn+0x1a5/0x6b0 kernel/time/timer.c:1421
 expire_timers kernel/time/timer.c:1466 [inline]
 __run_timers.part.0+0x679/0xa80 kernel/time/timer.c:1737
 __run_timers kernel/time/timer.c:1715 [inline]
 run_timer_softirq+0xb3/0x1d0 kernel/time/timer.c:1750
 __do_softirq+0x29b/0x9c2 kernel/softirq.c:558
 invoke_softirq kernel/softirq.c:432 [inline]
 __irq_exit_rcu+0x123/0x180 kernel/softirq.c:637
 irq_exit_rcu+0x5/0x20 kernel/softirq.c:649
 sysvec_apic_timer_interrupt+0x93/0xc0 arch/x86/kernel/apic/apic.c:1097
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:645
RIP: 0010:finish_task_switch.isra.0+0x323/0xb80 kernel/sched/core.c:4953
Code: 33 92 1b 08 85 c0 75 02 0f 0b 48 85 db 0f 85 25 01 00 00 4c 89 f7 e8 fc f7 ff ff e8 d7 c3 2d 00 fb 65 48 8b 1c 25 00 70 02 00 <48> 8d bb 80 15 00 00 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1
RSP: 0018:ffffc9000445f9e8 EFLAGS: 00000202
RAX: 0000000000d44bb5 RBX: ffff88805e70bb00 RCX: 1ffffffff2018c0e
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc9000445fa30 R08: 0000000000000001 R09: ffffffff9006e9ef
R10: 0000000000000001 R11: 0000000000000001 R12: ffff8880b9c3ad58
R13: ffff88805fa05880 R14: ffff8880b9c3a000 R15: ffff8880b9c3aa38
 context_switch kernel/sched/core.c:5076 [inline]
 __schedule+0xaa2/0x4cc0 kernel/sched/core.c:6388
 preempt_schedule_common+0x45/0xc0 kernel/sched/core.c:6553
 preempt_schedule_thunk+0x16/0x18 arch/x86/entry/thunk_64.S:35
 __local_bh_enable_ip+0x109/0x120 kernel/softirq.c:390
 spin_unlock_bh include/linux/spinlock.h:394 [inline]
 batadv_nc_purge_paths+0x2a5/0x3a0 net/batman-adv/network-coding.c:471
 batadv_nc_worker+0x930/0xfa0 net/batman-adv/network-coding.c:722
 process_one_work+0x996/0x1610 kernel/workqueue.c:2289
 worker_thread+0x665/0x1080 kernel/workqueue.c:2436
 kthread+0x2e9/0x3a0 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298
 </TASK>
Modules linked in:
CR2: 0000000000000000
---[ end trace 0000000000000000 ]---
RIP: 0010:0x0
Code: Unable to access opcode bytes at RIP 0xffffffffffffffd6.
RSP: 0018:ffffc90000007a60 EFLAGS: 00010246
RAX: dffffc0000000000 RBX: ffff88807d6bab50 RCX: 0000000000000100
RDX: 1ffff1100fad756b RSI: ffff888047abc000 RDI: ffff888045febc00
RBP: ffff888045febc00 R08: 0000000000000000 R09: 0000000000000000
R10: ffffffff87d5df57 R11: 0000000000000000 R12: ffff888047abc000
R13: 0000000000000000 R14: ffff888045fec360 R15: ffff88801e1a492c
FS:  0000000000000000(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffffffffffffd6 CR3: 000000004e361000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess):
   0:	33 92 1b 08 85 c0    	xor    -0x3f7af7e5(%rdx),%edx
   6:	75 02                	jne    0xa
   8:	0f 0b                	ud2
   a:	48 85 db             	test   %rbx,%rbx
   d:	0f 85 25 01 00 00    	jne    0x138
  13:	4c 89 f7             	mov    %r14,%rdi
  16:	e8 fc f7 ff ff       	callq  0xfffff817
  1b:	e8 d7 c3 2d 00       	callq  0x2dc3f7
  20:	fb                   	sti
  21:	65 48 8b 1c 25 00 70 	mov    %gs:0x27000,%rbx
  28:	02 00
* 2a:	48 8d bb 80 15 00 00 	lea    0x1580(%rbx),%rdi <-- trapping instruction
  31:	48 b8 00 00 00 00 00 	movabs $0xdffffc0000000000,%rax
  38:	fc ff df
  3b:	48 89 fa             	mov    %rdi,%rdx
  3e:	48                   	rex.W
  3f:	c1                   	.byte 0xc1