general protection fault in ip_rt_get

Kernel	Title	Rank 🛈	Repro	Cause bisect	Fix bisect	Count	Last	Reported	Patched	Status
upstream	general protection fault in ip_rt_get_source (2) net	2				1	270d	270d	0/29	closed as invalid on 2025/01/15 13:14

general protection fault, probably for non-canonical address 0xdffffc000000001b: 0000 [#1] PREEMPT SMP KASAN KASAN: null-ptr-deref in range [0x00000000000000d8-0x00000000000000df] CPU: 1 PID: 17687 Comm: syz-executor.2 Not tainted 6.2.0-rc7-syzkaller-00112-gc68f345b7c42 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/21/2023 RIP: 0010:ip_rt_get_source+0x264/0x760 net/ipv4/route.c:1286 Code: 00 fc ff df 80 3c 02 00 0f 85 b1 04 00 00 48 b8 00 00 00 00 00 fc ff df 4c 8b 7b 10 49 8d bf d8 00 00 00 48 89 fa 48 c1 ea 03 <0f> b6 04 02 84 c0 74 08 3c 03 0f 8e 1d 04 00 00 41 8b 87 d8 00 00 RSP: 0018:ffffc90015fa65f0 EFLAGS: 00010206 RAX: dffffc0000000000 RBX: ffff88807e09fc80 RCX: 0000000000000000 RDX: 000000000000001b RSI: ffffffff884c55d2 RDI: 00000000000000d8 RBP: ffff8880439f4200 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000001 R12: 1ffff92002bf4cbf R13: ffff88801c6f5410 R14: ffff88801c6f5442 R15: 0000000000000000 FS: 00007f2f46d90700(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000000 CR3: 0000000017e4b000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <TASK> ip_options_build+0x2f9/0x510 net/ipv4/ip_options.c:57 __ip_make_skb+0xc7a/0x1960 net/ipv4/ip_output.c:1560 ip_finish_skb include/net/ip.h:242 [inline] ip_push_pending_frames+0x34/0x2b0 net/ipv4/ip_output.c:1601 icmp_push_reply+0x319/0x440 net/ipv4/icmp.c:386 __icmp_send+0xb80/0x13f0 net/ipv4/icmp.c:762 ipv4_send_dest_unreach net/ipv4/route.c:1239 [inline] ipv4_link_failure+0x5aa/0x9b0 net/ipv4/route.c:1246 dst_link_failure include/net/dst.h:423 [inline] ip6_tnl_xmit+0x490/0x3950 net/ipv6/ip6_tunnel.c:1268 ipxip6_tnl_xmit net/ipv6/ip6_tunnel.c:1384 [inline] ip6_tnl_start_xmit+0x6dd/0x1700 net/ipv6/ip6_tunnel.c:1432 __netdev_start_xmit include/linux/netdevice.h:4865 [inline] netdev_start_xmit include/linux/netdevice.h:4879 [inline] xmit_one net/core/dev.c:3583 [inline] dev_hard_start_xmit+0x1c2/0x990 net/core/dev.c:3599 __dev_queue_xmit+0x2cdf/0x3ba0 net/core/dev.c:4249 dev_queue_xmit include/linux/netdevice.h:3035 [inline] neigh_connected_output+0x3c4/0x520 net/core/neighbour.c:1612 neigh_output include/net/neighbour.h:546 [inline] ip_finish_output2+0x78a/0x2180 net/ipv4/ip_output.c:228 __ip_finish_output net/ipv4/ip_output.c:306 [inline] __ip_finish_output+0x396/0x650 net/ipv4/ip_output.c:288 ip_finish_output+0x31/0x280 net/ipv4/ip_output.c:316 NF_HOOK_COND include/linux/netfilter.h:291 [inline] ip_output+0x1a3/0x320 net/ipv4/ip_output.c:430 dst_output include/net/dst.h:444 [inline] ip_local_out net/ipv4/ip_output.c:126 [inline] ip_send_skb+0xd8/0x260 net/ipv4/ip_output.c:1586 udp_send_skb+0x73a/0x1490 net/ipv4/udp.c:978 udp_sendmsg+0x1bba/0x2750 net/ipv4/udp.c:1265 udpv6_sendmsg+0x17dc/0x2c80 net/ipv6/udp.c:1400 inet6_sendmsg+0x9d/0xe0 net/ipv6/af_inet6.c:661 sock_sendmsg_nosec net/socket.c:714 [inline] sock_sendmsg+0xd3/0x120 net/socket.c:734 ____sys_sendmsg+0x334/0x8c0 net/socket.c:2476 ___sys_sendmsg+0x110/0x1b0 net/socket.c:2530 __sys_sendmmsg+0x18f/0x460 net/socket.c:2616 __do_sys_sendmmsg net/socket.c:2645 [inline] __se_sys_sendmmsg net/socket.c:2642 [inline] __x64_sys_sendmmsg+0x9d/0x100 net/socket.c:2642 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7f2f4608c0f9 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 f1 19 00 00 90 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 b8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f2f46d90168 EFLAGS: 00000246 ORIG_RAX: 0000000000000133 RAX: ffffffffffffffda RBX: 00007f2f461abf80 RCX: 00007f2f4608c0f9 RDX: 0000000000000001 RSI: 00000000200017c0 RDI: 0000000000000003 RBP: 00007f2f460e7ae9 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fffad20ff8f R14: 00007f2f46d90300 R15: 0000000000022000 </TASK> Modules linked in: ---[ end trace 0000000000000000 ]--- RIP: 0010:ip_rt_get_source+0x264/0x760 net/ipv4/route.c:1286 Code: 00 fc ff df 80 3c 02 00 0f 85 b1 04 00 00 48 b8 00 00 00 00 00 fc ff df 4c 8b 7b 10 49 8d bf d8 00 00 00 48 89 fa 48 c1 ea 03 <0f> b6 04 02 84 c0 74 08 3c 03 0f 8e 1d 04 00 00 41 8b 87 d8 00 00 RSP: 0018:ffffc90015fa65f0 EFLAGS: 00010206 RAX: dffffc0000000000 RBX: ffff88807e09fc80 RCX: 0000000000000000 RDX: 000000000000001b RSI: ffffffff884c55d2 RDI: 00000000000000d8 RBP: ffff8880439f4200 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000001 R12: 1ffff92002bf4cbf R13: ffff88801c6f5410 R14: ffff88801c6f5442 R15: 0000000000000000 FS: 00007f2f46d90700(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000000 CR3: 0000000017e4b000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 ---------------- Code disassembly (best guess), 4 bytes skipped: 0: 80 3c 02 00 cmpb $0x0,(%rdx,%rax,1) 4: 0f 85 b1 04 00 00 jne 0x4bb a: 48 b8 00 00 00 00 00 movabs $0xdffffc0000000000,%rax 11: fc ff df 14: 4c 8b 7b 10 mov 0x10(%rbx),%r15 18: 49 8d bf d8 00 00 00 lea 0xd8(%r15),%rdi 1f: 48 89 fa mov %rdi,%rdx 22: 48 c1 ea 03 shr $0x3,%rdx * 26: 0f b6 04 02 movzbl (%rdx,%rax,1),%eax <-- trapping instruction 2a: 84 c0 test %al,%al 2c: 74 08 je 0x36 2e: 3c 03 cmp $0x3,%al 30: 0f 8e 1d 04 00 00 jle 0x453 36: 41 rex.B 37: 8b .byte 0x8b 38: 87 d8 xchg %ebx,%eax