general protection fault, probably for non-canonical address 0xdffffc000000006b: 0000 [#1] PREEMPT SMP KASAN KASAN: null-ptr-deref in range [0x0000000000000358-0x000000000000035f] CPU: 0 PID: 6505 Comm: syz.3.514 Not tainted 5.15.187-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 RIP: 0010:ip_ignore_linkdown include/linux/inetdevice.h:254 [inline] RIP: 0010:fib_lookup_good_nhc+0x81/0x3d0 net/ipv4/fib_trie.c:1407 Code: 4c 89 24 24 48 89 d8 48 c1 e8 03 42 80 3c 28 00 74 08 48 89 df e8 1f b8 51 f9 41 bc 58 03 00 00 4c 03 23 4c 89 e0 48 c1 e8 03 <42> 80 3c 28 00 74 08 4c 89 e7 e8 00 b8 51 f9 4d 8b 24 24 e8 07 0f RSP: 0018:ffffc9000352f438 EFLAGS: 00010202 RAX: 000000000000006b RBX: ffff888024b12a20 RCX: ffff8880216d8000 RDX: 0000000000000002 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffff888024b12a2f R08: dffffc0000000000 R09: fffffbfff1ff7619 R10: fffffbfff1ff7619 R11: 1ffffffff1ff7618 R12: 0000000000000358 R13: dffffc0000000000 R14: 0000000000000000 R15: 1ffff11004962545 FS: 00007ffb94ca66c0(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000200000004ff0 CR3: 000000002b825000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: nexthop_get_nhc_lookup+0x1a8/0x400 include/net/nexthop.h:405 fib_table_lookup+0xe76/0x15e0 net/ipv4/fib_trie.c:1583 fib_lookup+0x192/0x400 include/net/ip_fib.h:381 ip_route_output_key_hash_rcu+0x305/0x2460 net/ipv4/route.c:2785 ip_route_output_key_hash+0x1b1/0x2e0 net/ipv4/route.c:2675 __ip_route_output_key include/net/route.h:126 [inline] ip_route_output_flow+0x26/0x150 net/ipv4/route.c:2905 ip_route_output_key include/net/route.h:142 [inline] sctp_v4_get_dst+0x34d/0x10d0 net/sctp/protocol.c:449 sctp_transport_route+0x107/0x2b0 net/sctp/transport.c:463 sctp_assoc_add_peer+0x615/0x15a0 net/sctp/associola.c:665 sctp_connect_new_asoc+0x300/0x690 net/sctp/socket.c:1097 sctp_sendmsg_new_asoc net/sctp/socket.c:1691 [inline] sctp_sendmsg+0x15e0/0x2950 net/sctp/socket.c:2005 sock_sendmsg_nosec net/socket.c:704 [inline] __sock_sendmsg net/socket.c:716 [inline] __sys_sendto+0x423/0x580 net/socket.c:2063 __do_sys_sendto net/socket.c:2075 [inline] __se_sys_sendto net/socket.c:2071 [inline] __x64_sys_sendto+0xda/0xf0 net/socket.c:2071 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 RIP: 0033:0x7ffb96e3e929 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:00007ffb94ca6038 EFLAGS: 00000246 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 00007ffb97065fa0 RCX: 00007ffb96e3e929 RDX: 0000000000034000 RSI: 0000200000000140 RDI: 0000000000000003 RBP: 00007ffb96ec0b39 R08: 0000200000004ff0 R09: 0000000000000010 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007ffb97065fa0 R15: 00007ffe19ff1618 Modules linked in: ---[ end trace e77273149db18e12 ]--- RIP: 0010:ip_ignore_linkdown include/linux/inetdevice.h:254 [inline] RIP: 0010:fib_lookup_good_nhc+0x81/0x3d0 net/ipv4/fib_trie.c:1407 Code: 4c 89 24 24 48 89 d8 48 c1 e8 03 42 80 3c 28 00 74 08 48 89 df e8 1f b8 51 f9 41 bc 58 03 00 00 4c 03 23 4c 89 e0 48 c1 e8 03 <42> 80 3c 28 00 74 08 4c 89 e7 e8 00 b8 51 f9 4d 8b 24 24 e8 07 0f RSP: 0018:ffffc9000352f438 EFLAGS: 00010202 RAX: 000000000000006b RBX: ffff888024b12a20 RCX: ffff8880216d8000 RDX: 0000000000000002 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffff888024b12a2f R08: dffffc0000000000 R09: fffffbfff1ff7619 R10: fffffbfff1ff7619 R11: 1ffffffff1ff7618 R12: 0000000000000358 R13: dffffc0000000000 R14: 0000000000000000 R15: 1ffff11004962545 FS: 00007ffb94ca66c0(0000) GS:ffff8880b9100000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000562176e86950 CR3: 000000002b825000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 ---------------- Code disassembly (best guess): 0: 4c 89 24 24 mov %r12,(%rsp) 4: 48 89 d8 mov %rbx,%rax 7: 48 c1 e8 03 shr $0x3,%rax b: 42 80 3c 28 00 cmpb $0x0,(%rax,%r13,1) 10: 74 08 je 0x1a 12: 48 89 df mov %rbx,%rdi 15: e8 1f b8 51 f9 call 0xf951b839 1a: 41 bc 58 03 00 00 mov $0x358,%r12d 20: 4c 03 23 add (%rbx),%r12 23: 4c 89 e0 mov %r12,%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: 4c 89 e7 mov %r12,%rdi 34: e8 00 b8 51 f9 call 0xf951b839 39: 4d 8b 24 24 mov (%r12),%r12 3d: e8 .byte 0xe8 3e: 07 (bad) 3f: 0f .byte 0xf