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BUG: KMSAN: uninit-value in tcp_recvmsg+0x4fa/0xb60 net/ipv4/tcp.c:2560
 tcp_recvmsg+0x4fa/0xb60 net/ipv4/tcp.c:2560
 inet_recvmsg+0x13a/0x5a0 net/ipv4/af_inet.c:850
 ____sys_recvmsg+0x2d9/0x6c0
 ___sys_recvmsg+0x232/0x870 net/socket.c:2753
 do_recvmmsg+0x55f/0x10a0 net/socket.c:2847
 __sys_recvmmsg net/socket.c:2926 [inline]
 __do_sys_recvmmsg net/socket.c:2949 [inline]
 __se_sys_recvmmsg net/socket.c:2942 [inline]
 __x64_sys_recvmmsg+0x3a7/0x4b0 net/socket.c:2942
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x46/0xb0

Uninit was stored to memory at:
 __copy_msghdr_from_user net/socket.c:2377 [inline]
 copy_msghdr_from_user net/socket.c:2425 [inline]
 recvmsg_copy_msghdr net/socket.c:2677 [inline]
 ___sys_recvmsg+0x5cf/0x870 net/socket.c:2749
 do_recvmmsg+0x55f/0x10a0 net/socket.c:2847
 __sys_recvmmsg net/socket.c:2926 [inline]
 __do_sys_recvmmsg net/socket.c:2949 [inline]
 __se_sys_recvmmsg net/socket.c:2942 [inline]
 __x64_sys_recvmmsg+0x3a7/0x4b0 net/socket.c:2942
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x46/0xb0

Local variable msg_sys created at:
 do_recvmmsg+0x5f/0x10a0 net/socket.c:2808
 __sys_recvmmsg net/socket.c:2926 [inline]
 __do_sys_recvmmsg net/socket.c:2949 [inline]
 __se_sys_recvmmsg net/socket.c:2942 [inline]
 __x64_sys_recvmmsg+0x3a7/0x4b0 net/socket.c:2942

CPU: 0 PID: 6924 Comm: syz-executor.3 Not tainted 5.19.0-rc4-syzkaller-31333-g97117d69c353 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/22/2022
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