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BUG: KMSAN: uninit-value in memcmp lib/string.c:778 [inline]
BUG: KMSAN: uninit-value in bcmp+0x14e/0x290 lib/string.c:810
 memcmp lib/string.c:778 [inline]
 bcmp+0x14e/0x290 lib/string.c:810
 ____sys_sendmsg+0xa15/0x12c0 net/socket.c:2408
 ___sys_sendmsg net/socket.c:2467 [inline]
 __sys_sendmmsg+0xac2/0xf60 net/socket.c:2553
 __do_sys_sendmmsg net/socket.c:2582 [inline]
 __se_sys_sendmmsg net/socket.c:2579 [inline]
 __x64_sys_sendmmsg+0x11c/0x170 net/socket.c:2579
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x54/0xd0 arch/x86/entry/common.c:82
 entry_SYSCALL_64_after_hwframe+0x44/0xae

Uninit was stored to memory at:
 ____sys_sendmsg+0xfef/0x12c0 net/socket.c:2421
 ___sys_sendmsg net/socket.c:2467 [inline]
 __sys_sendmmsg+0xac2/0xf60 net/socket.c:2553
 __do_sys_sendmmsg net/socket.c:2582 [inline]
 __se_sys_sendmmsg net/socket.c:2579 [inline]
 __x64_sys_sendmmsg+0x11c/0x170 net/socket.c:2579
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x54/0xd0 arch/x86/entry/common.c:82
 entry_SYSCALL_64_after_hwframe+0x44/0xae

Local variable sin created at:
 udpv6_sendmsg+0x93/0x4f40 net/ipv6/udp.c:1293
 inet6_sendmsg+0x15b/0x1d0 net/ipv6/af_inet6.c:643

CPU: 1 PID: 6975 Comm: syz-executor.2 Tainted: G        W         5.17.0-rc4-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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