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BUG: KCSAN: data-race in __ip6_datagram_connect / udpv6_sendmsg

write to 0xffff8881043ccd0c of 2 bytes by task 11640 on cpu 0:
 __ip6_datagram_connect+0x74e/0x7e0 net/ipv6/datagram.c:262
 udpv6_connect+0x33/0x150 net/ipv6/udp.c:1310
 inet_dgram_connect+0x122/0x1c0 net/ipv4/af_inet.c:592
 __sys_connect_file net/socket.c:2038 [inline]
 __sys_connect+0x1ef/0x2b0 net/socket.c:2057
 __do_sys_connect net/socket.c:2063 [inline]
 __se_sys_connect net/socket.c:2060 [inline]
 __x64_sys_connect+0x3f/0x50 net/socket.c:2060
 x64_sys_call+0x1daa/0x2fb0 arch/x86/include/generated/asm/syscalls_64.h:43
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xd0/0x1a0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffff8881043ccd0c of 2 bytes by task 11641 on cpu 1:
 udpv6_sendmsg+0x91a/0x1570 net/ipv6/udp.c:1610
 inet6_sendmsg+0xac/0xd0 net/ipv6/af_inet6.c:659
 sock_sendmsg_nosec net/socket.c:712 [inline]
 __sock_sendmsg+0x8b/0x180 net/socket.c:727
 __sys_sendto+0x268/0x330 net/socket.c:2180
 __do_sys_sendto net/socket.c:2187 [inline]
 __se_sys_sendto net/socket.c:2183 [inline]
 __x64_sys_sendto+0x76/0x90 net/socket.c:2183
 x64_sys_call+0x2eb6/0x2fb0 arch/x86/include/generated/asm/syscalls_64.h:45
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xd0/0x1a0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x0000 -> 0x234e

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 UID: 0 PID: 11641 Comm: syz.3.2801 Not tainted 6.15.0-rc5-syzkaller-00353-gcd802e7e5f1e #0 PREEMPT(voluntary) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/19/2025
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