general protection fault, probably for non-canonical address 0xdffffc000000005a: 0000 [#1] PREEMPT SMP KASAN KASAN: null-ptr-deref in range [0x00000000000002d0-0x00000000000002d7] CPU: 0 PID: 20669 Comm: syz.1.5746 Not tainted 6.1.145-syzkaller-00002-gc750dc582629 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 RIP: 0010:ip_ignore_linkdown include/linux/inetdevice.h:259 [inline] RIP: 0010:fib_lookup_good_nhc net/ipv4/fib_trie.c:1413 [inline] RIP: 0010:nexthop_get_nhc_lookup+0x17e/0x750 include/net/nexthop.h:405 Code: d8 48 c1 e8 03 42 80 3c 28 00 74 08 48 89 df e8 78 15 7c fd 48 89 5d a8 48 8b 1b b8 d0 02 00 00 48 01 c3 48 89 d8 48 c1 e8 03 <42> 80 3c 28 00 74 08 48 89 df e8 53 15 7c fd 48 8b 1b 48 85 db 0f RSP: 0018:ffffc9000163f8f8 EFLAGS: 00010206 RAX: 000000000000005a RBX: 00000000000002d0 RCX: 0000000000000000 RDX: ffff888129f43cc0 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffc9000163f968 R08: dffffc0000000000 R09: ffffc9000163fb60 R10: fffff520002c7f72 R11: 1ffff920002c7f6c R12: ffff88811e5e1e00 R13: dffffc0000000000 R14: 0000000000000000 R15: ffff88810f4250d0 FS: 00007f845cd906c0(0000) GS:ffff8881f7000000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000000 CR3: 0000000108ea4000 CR4: 00000000003526b0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: fib_table_lookup+0x10b7/0x1a60 net/ipv4/fib_trie.c:1590 fib_lookup include/net/ip_fib.h:384 [inline] ip_route_output_key_hash_rcu+0x497/0x2060 net/ipv4/route.c:2781 ip_route_output_key_hash+0x131/0x1e0 net/ipv4/route.c:2671 __ip_route_output_key include/net/route.h:137 [inline] ip_route_connect include/net/route.h:324 [inline] __ip4_datagram_connect+0x682/0x1030 net/ipv4/datagram.c:49 ip4_datagram_connect+0x2d/0x40 net/ipv4/datagram.c:90 inet_dgram_connect+0x212/0x450 net/ipv4/af_inet.c:589 __sys_connect_file net/socket.c:2001 [inline] __sys_connect+0x398/0x420 net/socket.c:2018 __do_sys_connect net/socket.c:2028 [inline] __se_sys_connect net/socket.c:2025 [inline] __x64_sys_connect+0x7a/0x90 net/socket.c:2025 x64_sys_call+0x88d/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:43 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f845bf8ebe9 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f845cd90038 EFLAGS: 00000246 ORIG_RAX: 000000000000002a RAX: ffffffffffffffda RBX: 00007f845c1b5fa0 RCX: 00007f845bf8ebe9 RDX: 0000000000000010 RSI: 0000200000000480 RDI: 0000000000000004 RBP: 00007f845c011e19 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f845c1b6038 R14: 00007f845c1b5fa0 R15: 00007ffdbf44cbc8 Modules linked in: ---[ end trace 0000000000000000 ]--- RIP: 0010:ip_ignore_linkdown include/linux/inetdevice.h:259 [inline] RIP: 0010:fib_lookup_good_nhc net/ipv4/fib_trie.c:1413 [inline] RIP: 0010:nexthop_get_nhc_lookup+0x17e/0x750 include/net/nexthop.h:405 Code: d8 48 c1 e8 03 42 80 3c 28 00 74 08 48 89 df e8 78 15 7c fd 48 89 5d a8 48 8b 1b b8 d0 02 00 00 48 01 c3 48 89 d8 48 c1 e8 03 <42> 80 3c 28 00 74 08 48 89 df e8 53 15 7c fd 48 8b 1b 48 85 db 0f RSP: 0018:ffffc9000163f8f8 EFLAGS: 00010206 RAX: 000000000000005a RBX: 00000000000002d0 RCX: 0000000000000000 RDX: ffff888129f43cc0 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffc9000163f968 R08: dffffc0000000000 R09: ffffc9000163fb60 R10: fffff520002c7f72 R11: 1ffff920002c7f6c R12: ffff88811e5e1e00 R13: dffffc0000000000 R14: 0000000000000000 R15: ffff88810f4250d0 FS: 00007f845cd906c0(0000) GS:ffff8881f7100000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f845cd6ef98 CR3: 0000000108ea4000 CR4: 00000000003526a0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 ---------------- Code disassembly (best guess): 0: d8 48 c1 fmuls -0x3f(%rax) 3: e8 03 42 80 3c call 0x3c80420b 8: 28 00 sub %al,(%rax) a: 74 08 je 0x14 c: 48 89 df mov %rbx,%rdi f: e8 78 15 7c fd call 0xfd7c158c 14: 48 89 5d a8 mov %rbx,-0x58(%rbp) 18: 48 8b 1b mov (%rbx),%rbx 1b: b8 d0 02 00 00 mov $0x2d0,%eax 20: 48 01 c3 add %rax,%rbx 23: 48 89 d8 mov %rbx,%rax 26: 48 c1 e8 03 shr $0x3,%rax * 2a: 42 80 3c 28 00 cmpb $0x0,(%rax,%r13,1) <-- trapping instruction 2f: 74 08 je 0x39 31: 48 89 df mov %rbx,%rdi 34: e8 53 15 7c fd call 0xfd7c158c 39: 48 8b 1b mov (%rbx),%rbx 3c: 48 85 db test %rbx,%rbx 3f: 0f .byte 0xf