===================================================== 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 __sys_recvmsg+0x2ab/0x430 net/socket.c:2773 __compat_sys_recvmsg net/compat.c:371 [inline] __do_compat_sys_recvmsg net/compat.c:378 [inline] __se_compat_sys_recvmsg net/compat.c:375 [inline] __ia32_compat_sys_recvmsg+0x99/0xe0 net/compat.c:375 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 __sys_recvmsg+0x2ab/0x430 net/socket.c:2773 __compat_sys_recvmsg net/compat.c:371 [inline] __do_compat_sys_recvmsg net/compat.c:378 [inline] __se_compat_sys_recvmsg net/compat.c:375 [inline] __ia32_compat_sys_recvmsg+0x99/0xe0 net/compat.c:375 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: __sys_recvmsg+0x51/0x430 net/socket.c:2763 __compat_sys_recvmsg net/compat.c:371 [inline] __do_compat_sys_recvmsg net/compat.c:378 [inline] __se_compat_sys_recvmsg net/compat.c:375 [inline] __ia32_compat_sys_recvmsg+0x99/0xe0 net/compat.c:375 CPU: 1 PID: 11418 Comm: syz-executor.3 Not tainted 6.0.0-rc5-syzkaller-48543-g968c2729e576 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/11/2022 =====================================================