Oops: general protection fault, probably for non-canonical address 0xdffffc0000000083: 0000 [#1] SMP KASAN PTI KASAN: null-ptr-deref in range [0x0000000000000418-0x000000000000041f] CPU: 0 UID: 0 PID: 11013 Comm: syz.5.1640 Not tainted 6.16.0-rc1-syzkaller-00203-g4774cfe3543a #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 1b 79 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 fc 78 30 f8 4d 8b 24 24 e8 93 f4 RSP: 0018:ffffc900000065d0 EFLAGS: 00010202 RAX: 0000000000000083 RBX: ffff8880268f9a20 RCX: 0000000000000100 RDX: ffff88802a3eda00 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffff8880268f9a37 R08: 0000000000000000 R09: ffffffff89d46d16 R10: ffffc900000068a0 R11: fffff52000000d1a R12: 0000000000000418 R13: dffffc0000000000 R14: 0000000000000000 R15: 1ffff11004d1f346 FS: 0000000000000000(0000) GS:ffff888125c52000(0063) knlGS:00000000f5015b40 CS: 0010 DS: 002b ES: 002b CR0: 0000000080050033 CR2: 00000000801d8018 CR3: 0000000077e9a000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 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 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 ipip6_tunnel_xmit net/ipv6/sit.c:946 [inline] sit_tunnel_xmit+0x86b/0x1fc0 net/ipv6/sit.c:1079 __netdev_start_xmit include/linux/netdevice.h:5215 [inline] netdev_start_xmit include/linux/netdevice.h:5224 [inline] xmit_one net/core/dev.c:3830 [inline] dev_hard_start_xmit+0x2d4/0x830 net/core/dev.c:3846 __dev_queue_xmit+0x1adf/0x3a70 net/core/dev.c:4713 neigh_output include/net/neighbour.h:539 [inline] ip6_finish_output2+0x11fb/0x16a0 net/ipv6/ip6_output.c:141 __ip6_finish_output net/ipv6/ip6_output.c:-1 [inline] ip6_finish_output+0x234/0x7d0 net/ipv6/ip6_output.c:226 ip6tunnel_xmit include/net/ip6_tunnel.h:161 [inline] udp_tunnel6_xmit_skb+0x5da/0xa60 net/ipv6/ip6_udp_tunnel.c:111 geneve6_xmit_skb drivers/net/geneve.c:1013 [inline] geneve_xmit+0x1cc7/0x2b70 drivers/net/geneve.c:1043 __netdev_start_xmit include/linux/netdevice.h:5215 [inline] netdev_start_xmit include/linux/netdevice.h:5224 [inline] xmit_one net/core/dev.c:3830 [inline] dev_hard_start_xmit+0x2d4/0x830 net/core/dev.c:3846 __dev_queue_xmit+0x1adf/0x3a70 net/core/dev.c:4713 neigh_output include/net/neighbour.h:539 [inline] ip6_finish_output2+0x11fb/0x16a0 net/ipv6/ip6_output.c:141 __ip6_finish_output net/ipv6/ip6_output.c:-1 [inline] ip6_finish_output+0x234/0x7d0 net/ipv6/ip6_output.c:226 NF_HOOK include/linux/netfilter.h:317 [inline] ndisc_send_skb+0xb47/0x1400 net/ipv6/ndisc.c:513 addrconf_rs_timer+0x369/0x670 net/ipv6/addrconf.c:4041 call_timer_fn+0x17e/0x5f0 kernel/time/timer.c:1747 expire_timers kernel/time/timer.c:1798 [inline] __run_timers kernel/time/timer.c:2372 [inline] __run_timer_base+0x61a/0x860 kernel/time/timer.c:2384 run_timer_base kernel/time/timer.c:2393 [inline] run_timer_softirq+0xb7/0x180 kernel/time/timer.c:2403 handle_softirqs+0x286/0x870 kernel/softirq.c:579 __do_softirq kernel/softirq.c:613 [inline] invoke_softirq kernel/softirq.c:453 [inline] __irq_exit_rcu+0xca/0x1f0 kernel/softirq.c:680 irq_exit_rcu+0x9/0x30 kernel/softirq.c:696 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1050 [inline] sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1050 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:native_save_fl arch/x86/include/asm/irqflags.h:26 [inline] RIP: 0010:arch_local_save_flags arch/x86/include/asm/irqflags.h:109 [inline] RIP: 0010:arch_local_irq_save arch/x86/include/asm/irqflags.h:127 [inline] RIP: 0010:lock_is_held_type+0x65/0x190 kernel/locking/lockdep.c:5939 Code: 85 ef 00 00 00 65 4c 8b 2c 25 08 e0 9c 92 41 83 bd ec 0a 00 00 00 0f 85 d8 00 00 00 89 f5 49 89 fe 48 c7 04 24 00 00 00 00 9c <8f> 04 24 4c 8b 24 24 fa 48 c7 c7 5d 54 99 8d e8 e7 16 00 00 65 ff RSP: 0018:ffffc9000dadf730 EFLAGS: 00000246 RAX: 0000000000000000 RBX: 00000000ffffffff RCX: ffff88802a3eda00 RDX: 0000000000000000 RSI: 00000000ffffffff RDI: ffffffff8e13edc0 RBP: 00000000ffffffff R08: 0000000000000003 R09: 0000000000000000 R10: ffffc9000dadf960 R11: fffff52001b5bf2f R12: dffffc0000000000 R13: ffff88802a3eda00 R14: ffffffff8e13edc0 R15: 0000000000000000 lock_is_held include/linux/lockdep.h:249 [inline] __might_resched+0xa6/0x610 kernel/sched/core.c:8762 __might_fault+0x77/0x130 mm/memory.c:6989 _inline_copy_from_user include/linux/uaccess.h:162 [inline] _copy_from_user+0x28/0xb0 lib/usercopy.c:18 copy_from_user include/linux/uaccess.h:212 [inline] get_compat_msghdr+0xad/0x4a0 net/compat.c:91 recvmsg_copy_msghdr net/socket.c:2750 [inline] ___sys_recvmsg+0x17f/0x510 net/socket.c:2824 do_recvmmsg+0x36a/0x770 net/socket.c:2915 __sys_recvmmsg+0x19d/0x280 net/socket.c:2997 __do_compat_sys_recvmmsg_time32 net/compat.c:418 [inline] __se_compat_sys_recvmmsg_time32 net/compat.c:414 [inline] __ia32_compat_sys_recvmmsg_time32+0xbf/0xe0 net/compat.c:414 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: 0023:0xf7f13539 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:00000000f501555c EFLAGS: 00000206 ORIG_RAX: 0000000000000151 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00000000800000c0 RDX: 0000000000010106 RSI: 0000000000000002 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 1b 79 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 fc 78 30 f8 4d 8b 24 24 e8 93 f4 RSP: 0018:ffffc900000065d0 EFLAGS: 00010202 RAX: 0000000000000083 RBX: ffff8880268f9a20 RCX: 0000000000000100 RDX: ffff88802a3eda00 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffff8880268f9a37 R08: 0000000000000000 R09: ffffffff89d46d16 R10: ffffc900000068a0 R11: fffff52000000d1a R12: 0000000000000418 R13: dffffc0000000000 R14: 0000000000000000 R15: 1ffff11004d1f346 FS: 0000000000000000(0000) GS:ffff888125c52000(0063) knlGS:00000000f5015b40 CS: 0010 DS: 002b ES: 002b CR0: 0000000080050033 CR2: 00000000801d8018 CR3: 0000000077e9a000 CR4: 00000000003526f0 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 1b 79 30 f8 call 0xf8307935 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 fc 78 30 f8 call 0xf8307935 39: 4d 8b 24 24 mov (%r12),%r12 3d: e8 .byte 0xe8 3e: 93 xchg %eax,%ebx 3f: f4 hlt