------------[ cut here ]------------
WARNING: net/core/skbuff.c:7243 at skb_attempt_defer_free+0x641/0x710 net/core/skbuff.c:7243, CPU#0: syz.3.625/8035
Modules linked in:
CPU: 0 UID: 0 PID: 8035 Comm: syz.3.625 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
RIP: 0010:skb_attempt_defer_free+0x641/0x710 net/core/skbuff.c:7243
Code: 64 e6 f8 e9 5d ff ff ff e8 2c 8a 7c f8 90 0f 0b 90 e9 f0 fc ff ff e8 1e 8a 7c f8 90 0f 0b 90 e9 74 fc ff ff e8 10 8a 7c f8 90 <0f> 0b 90 e9 95 fc ff ff e8 02 8a 7c f8 90 0f 0b 90 48 b8 00 00 00
RSP: 0018:ffffc90005ee75a8 EFLAGS: 00010287
RAX: 00000000000010d4 RBX: ffff88802d4e1680 RCX: ffffc9002a608000
RDX: 0000000000080000 RSI: ffffffff89425cb0 RDI: ffff88802d4e16e0
RBP: 0000000000000002 R08: 0000000000000007 R09: 0000000000000001
R10: 0000000000000000 R11: ffff888054930b30 R12: 0000000000000000
R13: 1ffff92000bdceb9 R14: 0000000000000000 R15: ffff88802d4e16d8
FS:  00007f96356986c0(0000) GS:ffff8880d68f5000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f155c23cf98 CR3: 000000002b876000 CR4: 0000000000352ef0
Call Trace:
 <TASK>
 skb_consume_udp+0x19f/0x250 net/ipv4/udp.c:1854
 udp_recvmsg+0x6c7/0x1350 net/ipv4/udp.c:2145
 sk_udp_recvmsg+0x9b/0x120 net/ipv4/udp_bpf.c:20
 udp_bpf_recvmsg net/ipv4/udp_bpf.c:94 [inline]
 udp_bpf_recvmsg+0x5c0/0xe40 net/ipv4/udp_bpf.c:62
 inet_recvmsg+0x625/0x6a0 net/ipv4/af_inet.c:891
 sock_recvmsg_nosec net/socket.c:1078 [inline]
 sock_recvmsg+0x1b2/0x250 net/socket.c:1100
 ____sys_recvmsg+0x218/0x6b0 net/socket.c:2812
 ___sys_recvmsg+0x114/0x1a0 net/socket.c:2854
 do_recvmmsg+0x2fe/0x750 net/socket.c:2949
 __sys_recvmmsg net/socket.c:3023 [inline]
 __do_sys_recvmmsg net/socket.c:3046 [inline]
 __se_sys_recvmmsg net/socket.c:3039 [inline]
 __x64_sys_recvmmsg+0x22a/0x280 net/socket.c:3039
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xcd/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f963478f7c9
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 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f9635698038 EFLAGS: 00000246 ORIG_RAX: 000000000000012b
RAX: ffffffffffffffda RBX: 00007f96349e6090 RCX: 00007f963478f7c9
RDX: 0000000000000001 RSI: 00002000000047c0 RDI: 0000000000000005
RBP: 00007f9634813f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000002 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f96349e6128 R14: 00007f96349e6090 R15: 00007ffdb142c378
 </TASK>