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BUG: KCSAN: data-race in __ip4_datagram_connect / __ip_make_skb

read to 0xffff8881049d756a of 2 bytes by task 16915 on cpu 0:
 ip_select_ident_segs include/net/ip.h:535 [inline]
 ip_select_ident include/net/ip.h:550 [inline]
 __ip_make_skb+0x817/0xc70 net/ipv4/ip_output.c:1557
 ip_make_skb+0x233/0x2c0 net/ipv4/ip_output.c:1671
 udp_sendmsg+0x114b/0x1220 net/ipv4/udp.c:1260
 inet_sendmsg+0x63/0x80 net/ipv4/af_inet.c:827
 sock_sendmsg_nosec net/socket.c:724 [inline]
 sock_sendmsg net/socket.c:747 [inline]
 ____sys_sendmsg+0x375/0x4c0 net/socket.c:2503
 ___sys_sendmsg net/socket.c:2557 [inline]
 __sys_sendmmsg+0x263/0x500 net/socket.c:2643
 __do_sys_sendmmsg net/socket.c:2672 [inline]
 __se_sys_sendmmsg net/socket.c:2669 [inline]
 __x64_sys_sendmmsg+0x57/0x60 net/socket.c:2669
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

write to 0xffff8881049d756a of 2 bytes by task 16917 on cpu 1:
 __ip4_datagram_connect+0x759/0x7b0 net/ipv4/datagram.c:76
 ip4_datagram_connect+0x2e/0x40 net/ipv4/datagram.c:90
 inet_dgram_connect+0x114/0x1a0 net/ipv4/af_inet.c:579
 __sys_connect_file net/socket.c:2003 [inline]
 __sys_connect+0x19b/0x1b0 net/socket.c:2020
 __do_sys_connect net/socket.c:2030 [inline]
 __se_sys_connect net/socket.c:2027 [inline]
 __x64_sys_connect+0x41/0x50 net/socket.c:2027
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

value changed: 0xf499 -> 0xf49a

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 16917 Comm: syz-executor.4 Not tainted 6.4.0-rc6-syzkaller-00242-g1639fae5132b #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/27/2023
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