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BUG: KMSAN: uninit-value in tcp_recvmsg+0x4fa/0xb60 net/ipv4/tcp.c:2676
 tcp_recvmsg+0x4fa/0xb60 net/ipv4/tcp.c:2676
 inet_recvmsg+0x13a/0x5a0 net/ipv4/af_inet.c:850
 ____sys_recvmsg+0x2c4/0x810
 ___sys_recvmsg+0x217/0x840 net/socket.c:2743
 do_recvmmsg+0x682/0x1180 net/socket.c:2829
 __sys_recvmmsg+0x113/0x450 net/socket.c:2916
 __do_compat_sys_recvmmsg_time32 net/compat.c:415 [inline]
 __se_compat_sys_recvmmsg_time32 net/compat.c:411 [inline]
 __ia32_compat_sys_recvmmsg_time32+0xf1/0x180 net/compat.c:411
 do_syscall_32_irqs_on arch/x86/entry/common.c:112 [inline]
 __do_fast_syscall_32+0xa2/0x100 arch/x86/entry/common.c:178
 do_fast_syscall_32+0x33/0x70 arch/x86/entry/common.c:203
 do_SYSENTER_32+0x1b/0x20 arch/x86/entry/common.c:246
 entry_SYSENTER_compat_after_hwframe+0x70/0x82

Uninit was stored to memory at:
 __get_compat_msghdr net/compat.c:54 [inline]
 get_compat_msghdr+0x4fc/0x720 net/compat.c:93
 recvmsg_copy_msghdr net/socket.c:2665 [inline]
 ___sys_recvmsg+0x18c/0x840 net/socket.c:2739
 do_recvmmsg+0x682/0x1180 net/socket.c:2829
 __sys_recvmmsg+0x113/0x450 net/socket.c:2916
 __do_compat_sys_recvmmsg_time32 net/compat.c:415 [inline]
 __se_compat_sys_recvmmsg_time32 net/compat.c:411 [inline]
 __ia32_compat_sys_recvmmsg_time32+0xf1/0x180 net/compat.c:411
 do_syscall_32_irqs_on arch/x86/entry/common.c:112 [inline]
 __do_fast_syscall_32+0xa2/0x100 arch/x86/entry/common.c:178
 do_fast_syscall_32+0x33/0x70 arch/x86/entry/common.c:203
 do_SYSENTER_32+0x1b/0x20 arch/x86/entry/common.c:246
 entry_SYSENTER_compat_after_hwframe+0x70/0x82

Local variable msg_sys created at:
 do_recvmmsg+0x5c/0x1180 net/socket.c:2798
 __sys_recvmmsg+0x113/0x450 net/socket.c:2916

CPU: 0 PID: 6074 Comm: syz-executor.2 Not tainted 6.0.0-rc5-syzkaller-48543-g968c2729e576 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/11/2022
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