------------[ cut here ]------------
WARNING: CPU: 0 PID: 29170 at net/ipv4/route.c:1283 kfree_skb include/linux/skbuff.h:1220 [inline]
WARNING: CPU: 0 PID: 29170 at net/ipv4/route.c:1283 ip_rt_bug+0x25/0xf0 net/ipv4/route.c:1282
Modules linked in:
CPU: 0 PID: 29170 Comm: syz.2.7254 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
RIP: 0010:ip_rt_bug+0x25/0xf0 net/ipv4/route.c:1283
Code: 41 ff ff ff 90 41 57 41 56 41 55 41 54 53 48 89 d3 e8 8f 10 d5 f8 66 90 e8 88 10 d5 f8 48 89 df be 01 00 00 00 e8 3b fb 7c ff <0f> 0b 31 c0 5b 41 5c 41 5d 41 5e 41 5f c3 49 bd 00 00 00 00 00 fc
RSP: 0018:ffffc90000007638 EFLAGS: 00010292
RAX: 4a6518e83449b900 RBX: ffff888026dfda00 RCX: 4a6518e83449b900
RDX: dffffc0000000000 RSI: ffffffff8a8c1220 RDI: ffffffff8adf0de0
RBP: ffff888054d6a200 R08: ffffffff90af52d7 R09: 1ffffffff215ea5a
R10: dffffc0000000000 R11: fffffbfff215ea5b R12: ffff888054d6a230
R13: ffff888026dfda58 R14: ffff888026dfda00 R15: ffff88801e280d00
FS:  00007f370557f6c0(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f7831b15ff8 CR3: 000000003937c000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 dst_output include/net/dst.h:453 [inline]
 ip_local_out net/ipv4/ip_output.c:126 [inline]
 ip_send_skb+0x129/0x1c0 net/ipv4/ip_output.c:1606
 __icmp_send+0x10af/0x1410 net/ipv4/icmp.c:785
 ipv4_send_dest_unreach net/ipv4/route.c:1263 [inline]
 ipv4_link_failure+0x667/0xa20 net/ipv4/route.c:1270
 dst_link_failure include/net/dst.h:423 [inline]
 arp_error_report+0x10e/0x160 net/ipv4/arp.c:296
 neigh_invalidate+0x22c/0x450 net/core/neighbour.c:1064
 neigh_timer_handler+0x911/0x1080 net/core/neighbour.c:1151
 call_timer_fn+0x1ac/0x670 kernel/time/timer.c:1701
 expire_timers kernel/time/timer.c:1752 [inline]
 __run_timers+0x53e/0x800 kernel/time/timer.c:2023
 run_timer_softirq+0x63/0xf0 kernel/time/timer.c:2036
 handle_softirqs+0x2a1/0x930 kernel/softirq.c:596
 __do_softirq kernel/softirq.c:630 [inline]
 invoke_softirq kernel/softirq.c:470 [inline]
 __irq_exit_rcu+0x13b/0x230 kernel/softirq.c:679
 irq_exit_rcu+0x5/0x20 kernel/softirq.c:691
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1118 [inline]
 sysvec_apic_timer_interrupt+0xa0/0xc0 arch/x86/kernel/apic/apic.c:1118
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:691
RIP: 0010:htab_unlock_bucket kernel/bpf/hashtab.c:180 [inline]
RIP: 0010:htab_map_update_elem+0x8de/0xb00 kernel/bpf/hashtab.c:1168
Code: 00 00 e8 65 45 e8 ff e9 be 00 00 00 e8 5b 45 e8 ff e8 b6 75 92 08 4d 85 e4 0f 84 c0 fd ff ff e8 48 45 e8 ff fb bf 01 00 00 00 <e8> 9d ba be ff 65 8b 1d 5e 3f 68 7e 31 ff 89 de e8 8d 48 e8 ff 85
RSP: 0018:ffffc9000d90fa60 EFLAGS: 00000246
RAX: ffffffff819a2fd8 RBX: 0000000000000000 RCX: 0000000000080000
RDX: ffffc90013271000 RSI: 000000000007ffff RDI: 0000000000000001
RBP: ffffc9000d90fb78 R08: ffff888054efe80b R09: 1ffff1100a9dfd01
R10: dffffc0000000000 R11: ffffed100a9dfd02 R12: 0000000000000200
R13: ffff8880682e5000 R14: 1ffff92001b21f5c R15: 0000000000000000
 bpf_map_update_value+0x59e/0x670 kernel/bpf/syscall.c:228
 generic_map_update_batch+0x54b/0x810 kernel/bpf/syscall.c:1709
 bpf_map_do_batch+0x466/0x600 kernel/bpf/syscall.c:-1
 __sys_bpf+0x6f7/0x780 kernel/bpf/syscall.c:-1
 __do_sys_bpf kernel/bpf/syscall.c:5134 [inline]
 __se_sys_bpf kernel/bpf/syscall.c:5132 [inline]
 __x64_sys_bpf+0x78/0x90 kernel/bpf/syscall.c:5132
 do_syscall_x64 arch/x86/entry/common.c:46 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f370479c629
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f370557f028 EFLAGS: 00000246 ORIG_RAX: 0000000000000141
RAX: ffffffffffffffda RBX: 00007f3704a15fa0 RCX: 00007f370479c629
RDX: 0000000000000038 RSI: 00002000000004c0 RDI: 000000000000001a
RBP: 00007f3704832b39 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f3704a16038 R14: 00007f3704a15fa0 R15: 00007fff3b489b68
 </TASK>
----------------
Code disassembly (best guess):
   0:	00 00                	add    %al,(%rax)
   2:	e8 65 45 e8 ff       	call   0xffe8456c
   7:	e9 be 00 00 00       	jmp    0xca
   c:	e8 5b 45 e8 ff       	call   0xffe8456c
  11:	e8 b6 75 92 08       	call   0x89275cc
  16:	4d 85 e4             	test   %r12,%r12
  19:	0f 84 c0 fd ff ff    	je     0xfffffddf
  1f:	e8 48 45 e8 ff       	call   0xffe8456c
  24:	fb                   	sti
  25:	bf 01 00 00 00       	mov    $0x1,%edi
* 2a:	e8 9d ba be ff       	call   0xffbebacc <-- trapping instruction
  2f:	65 8b 1d 5e 3f 68 7e 	mov    %gs:0x7e683f5e(%rip),%ebx        # 0x7e683f94
  36:	31 ff                	xor    %edi,%edi
  38:	89 de                	mov    %ebx,%esi
  3a:	e8 8d 48 e8 ff       	call   0xffe848cc
  3f:	85                   	.byte 0x85