general protection fault, probably for non-canonical address 0xdffffc000000005a: 0000 [#1] PREEMPT SMP KASAN KASAN: null-ptr-deref in range [0x00000000000002d0-0x00000000000002d7] CPU: 1 PID: 5017 Comm: syz.4.947 Not tainted syzkaller #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 08 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 08 7c fd 48 8b 1b 48 85 db 0f RSP: 0018:ffffc90000f1f1d8 EFLAGS: 00010206 RAX: 000000000000005a RBX: 00000000000002d0 RCX: 0000000000000002 RDX: ffff88811c97a880 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffc90000f1f248 R08: ffff88811c97a880 R09: 0000000000000003 R10: 0000000000000008 R11: 0000000000000002 R12: ffff888132bc2c00 R13: dffffc0000000000 R14: 0000000000000000 R15: ffffc90000f1f870 FS: 00007fc94daa86c0(0000) GS:ffff8881f7100000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b2eb14ff8 CR3: 000000011e442000 CR4: 00000000003506a0 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 fib4_rule_action+0x115/0x1a0 net/ipv4/fib_rules.c:136 fib_rules_lookup+0x4ae/0x900 net/core/fib_rules.c:318 __fib_lookup+0xe4/0x150 net/ipv4/fib_rules.c:93 fib_lookup include/net/ip_fib.h:376 [inline] ip_route_output_key_hash_rcu+0x33f/0x2060 net/ipv4/route.c:2781 ip_route_output_key_hash net/ipv4/route.c:2671 [inline] __ip_route_output_key include/net/route.h:137 [inline] ip_route_output_flow+0x12e/0x2e0 net/ipv4/route.c:2901 raw_sendmsg+0xa80/0x12e0 net/ipv4/raw.c:624 inet_sendmsg+0xb6/0xd0 net/ipv4/af_inet.c:841 sock_sendmsg_nosec net/socket.c:716 [inline] __sock_sendmsg net/socket.c:728 [inline] ____sys_sendmsg+0x5a9/0x990 net/socket.c:2509 ___sys_sendmsg+0x21c/0x290 net/socket.c:2563 __sys_sendmsg net/socket.c:2592 [inline] __do_sys_sendmsg net/socket.c:2601 [inline] __se_sys_sendmsg net/socket.c:2599 [inline] __x64_sys_sendmsg+0x1f0/0x2c0 net/socket.c:2599 x64_sys_call+0x171/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:47 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: 0033:0x7fc94cb8ebe9 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:00007fc94daa8038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007fc94cdc6180 RCX: 00007fc94cb8ebe9 RDX: 0000000000000000 RSI: 0000200000000780 RDI: 000000000000000b RBP: 00007fc94cc11e19 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fc94cdc6218 R14: 00007fc94cdc6180 R15: 00007ffebe53d8e8 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 08 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 08 7c fd 48 8b 1b 48 85 db 0f RSP: 0018:ffffc90000f1f1d8 EFLAGS: 00010206 RAX: 000000000000005a RBX: 00000000000002d0 RCX: 0000000000000002 RDX: ffff88811c97a880 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffc90000f1f248 R08: ffff88811c97a880 R09: 0000000000000003 R10: 0000000000000008 R11: 0000000000000002 R12: ffff888132bc2c00 R13: dffffc0000000000 R14: 0000000000000000 R15: ffffc90000f1f870 FS: 00007fc94daa86c0(0000) GS:ffff8881f7100000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b2eb14ff8 CR3: 000000011e442000 CR4: 00000000003506a0 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 08 7c fd call 0xfd7c088c 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 08 7c fd call 0xfd7c088c 39: 48 8b 1b mov (%rbx),%rbx 3c: 48 85 db test %rbx,%rbx 3f: 0f .byte 0xf