RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 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: 23517 Comm: syz.0.4997 Not tainted 6.16.0-rc3-syzkaller-00116-ge34a79b96ab9 #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 3b 19 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 1c 19 30 f8 4d 8b 24 24 e8 73 06 RSP: 0018:ffffc90004fae4b0 EFLAGS: 00010202 RAX: 0000000000000083 RBX: ffff88806beadc20 RCX: 0000000000000000 RDX: ffff88802e8d5a00 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffff88806beadc37 R08: ffffc90004fae72f R09: 0000000000000000 R10: ffffc90004fae700 R11: fffff520009f5ce6 R12: 0000000000000418 R13: dffffc0000000000 R14: 0000000000000000 R15: 1ffff1100d7d5b86 FS: 0000000000000000(0000) GS:ffff888125d50000(0063) knlGS:00000000f50ceb40 CS: 0010 DS: 002b ES: 002b CR0: 0000000080050033 CR2: 00000000f4bd9da4 CR3: 000000006c944000 CR4: 00000000003526f0 DR0: 0000040000000000 DR1: 000000000000064f DR2: 0000000000000006 DR3: 0000000016800000 DR6: 00000000fffe0ff0 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 __inet_dev_addr_type+0x2a2/0x4b0 net/ipv4/fib_frontend.c:225 inet_addr_type_dev_table net/ipv4/fib_frontend.c:267 [inline] fib_del_ifaddr+0x10f5/0x1480 net/ipv4/fib_frontend.c:1349 fib_inetaddr_event+0xbb/0x190 net/ipv4/fib_frontend.c:1477 notifier_call_chain+0x1b3/0x3e0 kernel/notifier.c:85 blocking_notifier_call_chain+0x6a/0x90 kernel/notifier.c:380 __inet_del_ifa+0x87d/0x1040 net/ipv4/devinet.c:451 inet_del_ifa net/ipv4/devinet.c:488 [inline] inetdev_destroy net/ipv4/devinet.c:328 [inline] inetdev_event+0x632/0x15b0 net/ipv4/devinet.c:1656 notifier_call_chain+0x1b3/0x3e0 kernel/notifier.c:85 call_netdevice_notifiers_mtu net/core/dev.c:2305 [inline] netif_set_mtu_ext+0x438/0x620 net/core/dev.c:9591 do_setlink+0x91a/0x41c0 net/core/rtnetlink.c:3104 rtnl_setlink+0x604/0x900 net/core/rtnetlink.c:3455 rtnetlink_rcv_msg+0x7cc/0xb70 net/core/rtnetlink.c:6944 netlink_rcv_skb+0x205/0x470 net/netlink/af_netlink.c:2534 netlink_unicast_kernel net/netlink/af_netlink.c:1313 [inline] netlink_unicast+0x758/0x8d0 net/netlink/af_netlink.c:1339 netlink_sendmsg+0x805/0xb30 net/netlink/af_netlink.c:1883 sock_sendmsg_nosec net/socket.c:712 [inline] __sock_sendmsg+0x219/0x270 net/socket.c:727 sock_write_iter+0x258/0x330 net/socket.c:1131 do_iter_readv_writev+0x56b/0x7f0 fs/read_write.c:-1 vfs_writev+0x31a/0x960 fs/read_write.c:1057 do_writev+0x14d/0x2d0 fs/read_write.c:1103 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: 0023:0xf70de539 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:00000000f50ce55c EFLAGS: 00000206 ORIG_RAX: 0000000000000092 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000080000440 RDX: 0000000000000001 RSI: 0000000000000000 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 3b 19 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 1c 19 30 f8 4d 8b 24 24 e8 73 06 RSP: 0018:ffffc90004fae4b0 EFLAGS: 00010202 RAX: 0000000000000083 RBX: ffff88806beadc20 RCX: 0000000000000000 RDX: ffff88802e8d5a00 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffff88806beadc37 R08: ffffc90004fae72f R09: 0000000000000000 R10: ffffc90004fae700 R11: fffff520009f5ce6 R12: 0000000000000418 R13: dffffc0000000000 R14: 0000000000000000 R15: 1ffff1100d7d5b86 FS: 0000000000000000(0000) GS:ffff888125d50000(0063) knlGS:00000000f50ceb40 CS: 0010 DS: 002b ES: 002b CR0: 0000000080050033 CR2: 000000002f610ff8 CR3: 000000006c944000 CR4: 00000000003526f0 DR0: 0000040000000000 DR1: 000000000000064f DR2: 0000000000000006 DR3: 0000000016800000 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 3b 19 30 f8 call 0xf8301955 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 1c 19 30 f8 call 0xf8301955 39: 4d 8b 24 24 mov (%r12),%r12 3d: e8 .byte 0xe8 3e: 73 06 jae 0x46