------------[ cut here ]------------
dst_release underflow
WARNING: CPU: 0 PID: 24692 at net/core/dst.c:173 dst_release net/core/dst.c:173 [inline]
WARNING: CPU: 0 PID: 24692 at net/core/dst.c:173 dst_release+0xd2/0xe0 net/core/dst.c:167
Modules linked in:
CPU: 0 PID: 24692 Comm: syz-executor.0 Not tainted 5.14.0-rc7-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:dst_release net/core/dst.c:173 [inline]
RIP: 0010:dst_release+0xd2/0xe0 net/core/dst.c:167
Code: 89 c3 89 c6 e8 8f 15 59 fa 85 db 74 a4 e9 b8 6d 0e 02 e8 41 0e 59 fa 48 c7 c7 80 19 8b 8a c6 05 3e cc 3b 06 01 e8 a7 e3 d0 01 <0f> 0b eb c6 66 2e 0f 1f 84 00 00 00 00 00 41 56 41 55 41 54 55 48
RSP: 0018:ffffc9000179f5d8 EFLAGS: 00010286
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
RDX: 0000000000040000 RSI: ffffffff815d87a5 RDI: fffff520002f3ead
RBP: ffff8880b9c52f00 R08: 0000000000000000 R09: 0000000000000000
R10: ffffffff815d25de R11: 0000000000000000 R12: ffff888000000000
R13: 00000000c00057ca R14: ffff888000000000 R15: ffff888065d1ac98
FS:  00007f971efea700(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b2d122000 CR3: 000000006162c000 CR4: 00000000001506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 rt_cache_route+0x2cd/0x360 net/ipv4/route.c:1482
 rt_set_nexthop.constprop.0+0x556/0x1460 net/ipv4/route.c:1591
 __mkroute_output net/ipv4/route.c:2599 [inline]
 ip_route_output_key_hash_rcu+0x9ea/0x2d00 net/ipv4/route.c:2799
 ip_route_output_key_hash+0x18b/0x300 net/ipv4/route.c:2627
 __ip_route_output_key include/net/route.h:126 [inline]
 ip_route_output_flow+0x23/0x150 net/ipv4/route.c:2858
 udp_sendmsg+0x1958/0x2740 net/ipv4/udp.c:1219
 inet_sendmsg+0x99/0xe0 net/ipv4/af_inet.c:821
 sock_sendmsg_nosec net/socket.c:704 [inline]
 sock_sendmsg+0xcf/0x120 net/socket.c:724
 ____sys_sendmsg+0x6e8/0x810 net/socket.c:2403
 ___sys_sendmsg+0xf3/0x170 net/socket.c:2457
 __sys_sendmsg+0xe5/0x1b0 net/socket.c:2486
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x4665f9
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 bc ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f971efea188 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 000000000056bf80 RCX: 00000000004665f9
RDX: 0000000000000000 RSI: 0000000020005b80 RDI: 0000000000000003
RBP: 00000000004bfcc4 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056bf80
R13: 00007ffe1a39565f R14: 00007f971efea300 R15: 0000000000022000