------------[ cut here ]------------ dst_release underflow WARNING: CPU: 0 PID: 21288 at net/core/dst.c:175 dst_release net/core/dst.c:175 [inline] WARNING: CPU: 0 PID: 21288 at net/core/dst.c:175 dst_release+0xd2/0xe0 net/core/dst.c:169 Modules linked in: CPU: 0 PID: 21288 Comm: syz-executor.0 Not tainted 5.11.0-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:175 [inline] RIP: 0010:dst_release+0xd2/0xe0 net/core/dst.c:169 Code: 89 c3 89 c6 e8 cf b3 77 fa 85 db 74 a4 e9 e4 66 fd 01 e8 41 ac 77 fa 48 c7 c7 c0 72 44 8a c6 05 0a 9b 94 06 01 e8 01 52 c1 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:ffffc9000299fd20 EFLAGS: 00010286 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000 RDX: 0000000000040000 RSI: ffffffff815b7595 RDI: fffff52000533f96 RBP: ffff8880262a69c0 R08: 0000000000000000 R09: 0000000000000000 R10: ffffffff815b076e R11: 0000000000000000 R12: ffff888029b5ab00 R13: 00000000ffffffff R14: ffff8880262a69c4 R15: 0000000000000000 FS: 00007f856508f700(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f7eb990d108 CR3: 000000001cfb1000 CR4: 00000000001506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: sk_dst_set include/net/sock.h:1999 [inline] sk_dst_reset include/net/sock.h:2011 [inline] __inet_bind+0x71f/0xbc0 net/ipv4/af_inet.c:549 inet_bind+0xf0/0x170 net/ipv4/af_inet.c:457 mptcp_bind+0x112/0x210 net/mptcp/protocol.c:3147 __sys_bind+0x1e9/0x250 net/socket.c:1635 __do_sys_bind net/socket.c:1646 [inline] __se_sys_bind net/socket.c:1644 [inline] __x64_sys_bind+0x6f/0xb0 net/socket.c:1644 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x465d99 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:00007f856508f188 EFLAGS: 00000246 ORIG_RAX: 0000000000000031 RAX: ffffffffffffffda RBX: 000000000056bf60 RCX: 0000000000465d99 RDX: 0000000000000010 RSI: 0000000020000080 RDI: 0000000000000005 RBP: 00000000004bcf27 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056bf60 R13: 00007fff1354464f R14: 00007f856508f300 R15: 0000000000022000