Oops: general protection fault, probably for non-canonical address 0xdffffc0000000083: 0000 [#1] SMP KASAN PTI KASAN: null-ptr-deref in range [0x0000000000000418-0x000000000000041f] CPU: 1 UID: 0 PID: 10771 Comm: syz.1.1201 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 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 8b 12 1b 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 6c 12 1b f8 4d 8b 24 24 e8 13 c5 RSP: 0018:ffffc9000b6370f0 EFLAGS: 00010202 RAX: 0000000000000083 RBX: ffff888067dabe20 RCX: 0000000000000002 RDX: ffff88802e89da00 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffff888067dabe37 R08: ffffc9000b63732f R09: 0000000000000000 R10: ffffc9000b637300 R11: fffff520016c6e66 R12: 0000000000000418 R13: dffffc0000000000 R14: 0000000000000000 R15: 1ffff1100cfb57c6 FS: 0000000000000000(0000) GS:ffff888125d18000(0063) knlGS:00000000f542cb40 CS: 0010 DS: 002b ES: 002b CR0: 0000000080050033 CR2: 0000000033512ffc CR3: 000000002ea24000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 000000000000000e DR6: 00000000ffff0ff0 DR7: 0000000000000400 Call Trace: nexthop_get_nhc_lookup+0x1af/0x400 include/net/nexthop.h:437 fib_table_lookup+0xf26/0x16e0 net/ipv4/fib_trie.c:1584 nl_fib_lookup net/ipv4/fib_frontend.c:1389 [inline] nl_fib_input+0x51c/0x950 net/ipv4/fib_frontend.c:1423 netlink_unicast_kernel net/netlink/af_netlink.c:1320 [inline] netlink_unicast+0x82c/0x9e0 net/netlink/af_netlink.c:1346 netlink_sendmsg+0x805/0xb30 net/netlink/af_netlink.c:1896 sock_sendmsg_nosec net/socket.c:714 [inline] __sock_sendmsg+0x219/0x270 net/socket.c:729 sock_sendmsg+0x158/0x230 net/socket.c:752 splice_to_socket+0x8ff/0xf10 fs/splice.c:886 do_splice_from fs/splice.c:938 [inline] direct_splice_actor+0xfe/0x160 fs/splice.c:1161 splice_direct_to_actor+0x5a8/0xcc0 fs/splice.c:1105 do_splice_direct_actor fs/splice.c:1204 [inline] do_splice_direct+0x181/0x270 fs/splice.c:1230 do_sendfile+0x4da/0x7e0 fs/read_write.c:1370 do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:83 [inline] __do_fast_syscall_32+0xb6/0x2b0 arch/x86/entry/syscall_32.c:306 do_fast_syscall_32+0x34/0x80 arch/x86/entry/syscall_32.c:331 entry_SYSENTER_compat_after_hwframe+0x84/0x8e RIP: 0023:0xf707e539 Code: 03 74 b4 01 10 07 03 74 b0 01 10 08 03 74 d8 01 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 RSP: 002b:00000000f542c55c EFLAGS: 00000206 ORIG_RAX: 00000000000000bb RAX: ffffffffffffffda RBX: 0000000000000006 RCX: 0000000000000007 RDX: 0000000000000000 RSI: 000000001d00c0d1 RDI: 0000000000000000 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 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 8b 12 1b 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 6c 12 1b f8 4d 8b 24 24 e8 13 c5 RSP: 0018:ffffc9000b6370f0 EFLAGS: 00010202 RAX: 0000000000000083 RBX: ffff888067dabe20 RCX: 0000000000000002 RDX: ffff88802e89da00 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffff888067dabe37 R08: ffffc9000b63732f R09: 0000000000000000 R10: ffffc9000b637300 R11: fffff520016c6e66 R12: 0000000000000418 R13: dffffc0000000000 R14: 0000000000000000 R15: 1ffff1100cfb57c6 FS: 0000000000000000(0000) GS:ffff888125d18000(0063) knlGS:00000000f542cb40 CS: 0010 DS: 002b ES: 002b CR0: 0000000080050033 CR2: 0000000033512ffc CR3: 000000002ea24000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 000000000000000e DR6: 00000000ffff0ff0 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 8b 12 1b f8 call 0xf81b12a5 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 6c 12 1b f8 call 0xf81b12a5 39: 4d 8b 24 24 mov (%r12),%r12 3d: e8 .byte 0xe8 3e: 13 c5 adc %ebp,%eax