syzbot

==================================================================
BUG: KCSAN: data-race in packet_sendmsg / packet_setsockopt

write to 0xffff88803e164530 of 8 bytes by task 16732 on cpu 1:
 packet_setsockopt+0xfde/0x23e0 net/packet/af_packet.c:3941
 __sys_setsockopt+0x2e8/0x460 net/socket.c:2117
 __do_sys_setsockopt net/socket.c:2128 [inline]
 __se_sys_setsockopt net/socket.c:2125 [inline]
 __x64_sys_setsockopt+0x62/0x70 net/socket.c:2125
 do_syscall_64+0x39/0x80 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xae

read to 0xffff88803e164530 of 8 bytes by task 16733 on cpu 0:
 packet_snd net/packet/af_packet.c:3006 [inline]
 packet_sendmsg+0x2d29/0x3460 net/packet/af_packet.c:3031
 sock_sendmsg_nosec net/socket.c:654 [inline]
 sock_sendmsg net/socket.c:674 [inline]
 ____sys_sendmsg+0x360/0x4d0 net/socket.c:2350
 ___sys_sendmsg net/socket.c:2404 [inline]
 __sys_sendmmsg+0x315/0x4b0 net/socket.c:2490
 __do_sys_sendmmsg net/socket.c:2519 [inline]
 __se_sys_sendmmsg net/socket.c:2516 [inline]
 __x64_sys_sendmmsg+0x53/0x60 net/socket.c:2516
 do_syscall_64+0x39/0x80 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xae

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 16733 Comm: syz-executor.0 Tainted: G        W         5.12.0-rc5-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================