syzbot

netlink: 42728 bytes leftover after parsing attributes in process `syz-executor309'.
netlink: 200 bytes leftover after parsing attributes in process `syz-executor309'.
kasan: CONFIG_KASAN_INLINE enabled
kasan: GPF could be caused by NULL-ptr deref or user memory access
general protection fault: 0000 [#1] PREEMPT SMP KASAN
Modules linked in:
CPU: 0 PID: 7957 Comm: syz-executor309 Not tainted 4.14.302-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022
task: ffff88809fd666c0 task.stack: ffff88809ad28000
RIP: 0010:ipt_init_target+0x97/0x250 net/sched/act_ipt.c:46
RSP: 0018:ffff88809ad2f160 EFLAGS: 00010202
RAX: 0000000000000005 RBX: dffffc0000000000 RCX: 0000000000000000
RDX: 0000000000000007 RSI: 0000000000000010 RDI: 000000000000002f
RBP: 0000000000000010 R08: 0000000000000001 R09: ffffed10165e9fa0
R10: ffff8880b2f4fd06 R11: 0000000000000000 R12: 1ffff110135a5e2f
R13: ffff88809ad2f1e8 R14: 0000000000000010 R15: ffffffff89cdb740
FS:  0000555556c7d300(0000) GS:ffff8880ba400000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000002000d300 CR3: 000000009cc98000 CR4: 00000000003406f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 __tcf_ipt_init+0x48d/0xc00 net/sched/act_ipt.c:168
 tcf_ipt_init+0x43/0x50 net/sched/act_ipt.c:202
 tcf_action_init_1+0x51a/0x9e0 net/sched/act_api.c:691
 tcf_action_init+0x26d/0x400 net/sched/act_api.c:760
 tcf_action_add net/sched/act_api.c:1088 [inline]
 tc_ctl_action+0x2e3/0x510 net/sched/act_api.c:1140
 rtnetlink_rcv_msg+0x3be/0xb10 net/core/rtnetlink.c:4322
 netlink_rcv_skb+0x125/0x390 net/netlink/af_netlink.c:2454
 netlink_unicast_kernel net/netlink/af_netlink.c:1296 [inline]
 netlink_unicast+0x437/0x610 net/netlink/af_netlink.c:1322
 netlink_sendmsg+0x648/0xbc0 net/netlink/af_netlink.c:1893
 sock_sendmsg_nosec net/socket.c:646 [inline]
 sock_sendmsg+0xb5/0x100 net/socket.c:656
 ___sys_sendmsg+0x6c8/0x800 net/socket.c:2062
 __sys_sendmsg+0xa3/0x120 net/socket.c:2096
 SYSC_sendmsg net/socket.c:2107 [inline]
 SyS_sendmsg+0x27/0x40 net/socket.c:2103
 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x5e/0xd3
RIP: 0033:0x7f9c96467059
RSP: 002b:00007ffde3272da8 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f9c96467059
RDX: 0000000000000000 RSI: 000000002000d300 RDI: 0000000000000003
RBP: 00007f9c9642b040 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f9c9642b0d0
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
Code: e8 ef b8 80 fb 31 c0 b9 0e 00 00 00 4c 8d ac 24 88 00 00 00 4c 89 ef f3 48 ab 48 8d 7d 1f 48 89 f8 48 89 fa 48 c1 e8 03 83 e2 07 <0f> b6 04 18 38 d0 7f 08 84 c0 0f 85 67 01 00 00 0f b6 55 1f 48 
RIP: ipt_init_target+0x97/0x250 net/sched/act_ipt.c:46 RSP: ffff88809ad2f160
---[ end trace 755f7805b88b1aba ]---
----------------
Code disassembly (best guess):
   0:	e8 ef b8 80 fb       	callq  0xfb80b8f4
   5:	31 c0                	xor    %eax,%eax
   7:	b9 0e 00 00 00       	mov    $0xe,%ecx
   c:	4c 8d ac 24 88 00 00 	lea    0x88(%rsp),%r13
  13:	00
  14:	4c 89 ef             	mov    %r13,%rdi
  17:	f3 48 ab             	rep stos %rax,%es:(%rdi)
  1a:	48 8d 7d 1f          	lea    0x1f(%rbp),%rdi
  1e:	48 89 f8             	mov    %rdi,%rax
  21:	48 89 fa             	mov    %rdi,%rdx
  24:	48 c1 e8 03          	shr    $0x3,%rax
  28:	83 e2 07             	and    $0x7,%edx
* 2b:	0f b6 04 18          	movzbl (%rax,%rbx,1),%eax <-- trapping instruction
  2f:	38 d0                	cmp    %dl,%al
  31:	7f 08                	jg     0x3b
  33:	84 c0                	test   %al,%al
  35:	0f 85 67 01 00 00    	jne    0x1a2
  3b:	0f b6 55 1f          	movzbl 0x1f(%rbp),%edx
  3f:	48                   	rex.W