Oops: general protection fault, probably for non-canonical address 0xdffffc0000000083: 0000 [#1] SMP KASAN NOPTI KASAN: null-ptr-deref in range [0x0000000000000418-0x000000000000041f] CPU: 1 UID: 0 PID: 13581 Comm: syz.2.2110 Not tainted 6.16.0-rc2-syzkaller-00024-g9afe652958c3 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 RIP: 0010:ip_ignore_linkdown include/linux/inetdevice.h:270 [inline] RIP: 0010:fib_lookup_good_nhc+0x85/0x3d0 net/ipv4/fib_trie.c:1408 Code: 4c 89 24 24 48 89 d8 48 c1 e8 03 42 80 3c 28 00 74 08 48 89 df e8 cb 7a 30 f8 41 bc 18 04 00 00 4c 03 23 4c 89 e0 48 c1 e8 03 <42> 80 3c 28 00 74 08 4c 89 e7 e8 ac 7a 30 f8 4d 8b 24 24 e8 93 ef RSP: 0018:ffffc90004cef3f0 EFLAGS: 00010212 RAX: 0000000000000083 RBX: ffff88802885cd20 RCX: 0000000000000002 RDX: ffff88804f2dbc00 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffff88802885cd37 R08: 0000000000000000 R09: ffffffff89d47216 R10: dffffc0000000000 R11: fffff5200099dede R12: 0000000000000418 R13: dffffc0000000000 R14: 0000000000000000 R15: 1ffff1100510b9a6 FS: 00007f535aee46c0(0000) GS:ffff888125d51000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000200000000200 CR3: 000000004dc07000 CR4: 0000000000350ef0 Call Trace: nexthop_get_nhc_lookup+0x1af/0x400 include/net/nexthop.h:437 fib_table_lookup+0xf26/0x16e0 net/ipv4/fib_trie.c:1584 fib_lookup+0x1c5/0x440 include/net/ip_fib.h:390 ip_route_output_key_hash_rcu+0x2fb/0x23a0 net/ipv4/route.c:2803 ip_route_output_key_hash+0x1b9/0x2e0 net/ipv4/route.c:2694 __ip_route_output_key include/net/route.h:169 [inline] ip_route_output_flow+0x2a/0x150 net/ipv4/route.c:2921 ip_route_output_key include/net/route.h:179 [inline] sctp_v4_get_dst+0x3c7/0x1200 net/sctp/protocol.c:454 sctp_transport_route+0x118/0x2f0 net/sctp/transport.c:457 sctp_assoc_add_peer+0x657/0x13b0 net/sctp/associola.c:663 sctp_connect_new_asoc+0x30a/0x690 net/sctp/socket.c:1100 __sctp_connect+0x5ba/0xd50 net/sctp/socket.c:1198 __sctp_setsockopt_connectx net/sctp/socket.c:1337 [inline] sctp_getsockopt_connectx3+0x2c4/0x440 net/sctp/socket.c:1422 sctp_getsockopt+0x98a/0xb60 net/sctp/socket.c:8134 do_sock_getsockopt+0x360/0x650 net/socket.c:2357 __sys_getsockopt net/socket.c:2386 [inline] __do_sys_getsockopt net/socket.c:2393 [inline] __se_sys_getsockopt net/socket.c:2390 [inline] __x64_sys_getsockopt+0x1a5/0x250 net/socket.c:2390 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f5359f8e929 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:00007f535aee4038 EFLAGS: 00000246 ORIG_RAX: 0000000000000037 RAX: ffffffffffffffda RBX: 00007f535a1b5fa0 RCX: 00007f5359f8e929 RDX: 000000000000006f RSI: 0000000000000084 RDI: 0000000000000004 RBP: 00007f535a010b39 R08: 0000200000000140 R09: 0000000000000000 R10: 0000200000000200 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f535a1b5fa0 R15: 00007ffd9982f638 Modules linked in: ---[ end trace 0000000000000000 ]--- RIP: 0010:ip_ignore_linkdown include/linux/inetdevice.h:270 [inline] RIP: 0010:fib_lookup_good_nhc+0x85/0x3d0 net/ipv4/fib_trie.c:1408 Code: 4c 89 24 24 48 89 d8 48 c1 e8 03 42 80 3c 28 00 74 08 48 89 df e8 cb 7a 30 f8 41 bc 18 04 00 00 4c 03 23 4c 89 e0 48 c1 e8 03 <42> 80 3c 28 00 74 08 4c 89 e7 e8 ac 7a 30 f8 4d 8b 24 24 e8 93 ef RSP: 0018:ffffc90004cef3f0 EFLAGS: 00010212 RAX: 0000000000000083 RBX: ffff88802885cd20 RCX: 0000000000000002 RDX: ffff88804f2dbc00 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffff88802885cd37 R08: 0000000000000000 R09: ffffffff89d47216 R10: dffffc0000000000 R11: fffff5200099dede R12: 0000000000000418 R13: dffffc0000000000 R14: 0000000000000000 R15: 1ffff1100510b9a6 FS: 00007f535aee46c0(0000) GS:ffff888125c51000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b2dd12ff8 CR3: 000000004dc07000 CR4: 0000000000350ef0 ---------------- 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 cb 7a 30 f8 call 0xf8307ae5 1a: 41 bc 18 04 00 00 mov $0x418,%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 ac 7a 30 f8 call 0xf8307ae5 39: 4d 8b 24 24 mov (%r12),%r12 3d: e8 .byte 0xe8 3e: 93 xchg %eax,%ebx 3f: ef out %eax,(%dx)