RBP: 000000000072bea0 R08: 0000000020001140 R09: 0000000000000010
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000014
R13: 0000000000000546 R14: 00000000006fbf30 R15: 0000000000000022
==================================================================
BUG: KMSAN: uninit-value in copy_to_user include/linux/uaccess.h:184 [inline]
BUG: KMSAN: uninit-value in move_addr_to_user+0x32e/0x530 net/socket.c:226
CPU: 1 PID: 11809 Comm: syz-executor6 Not tainted 4.17.0-rc3+ #88
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x185/0x1d0 lib/dump_stack.c:113
 kmsan_report+0x142/0x240 mm/kmsan/kmsan.c:1067
 kmsan_internal_check_memory+0x135/0x1e0 mm/kmsan/kmsan.c:1157
 kmsan_copy_to_user+0x69/0x160 mm/kmsan/kmsan.c:1199
 copy_to_user include/linux/uaccess.h:184 [inline]
 move_addr_to_user+0x32e/0x530 net/socket.c:226
 ___sys_recvmsg+0x4e2/0x810 net/socket.c:2285
 __sys_recvmmsg+0x58e/0xe30 net/socket.c:2391
 do_sys_recvmmsg+0x217/0x3e0 net/socket.c:2467
 __do_sys_recvmmsg net/socket.c:2485 [inline]
 __se_sys_recvmmsg net/socket.c:2481 [inline]
 __x64_sys_recvmmsg+0x15d/0x1c0 net/socket.c:2481
 do_syscall_64+0x154/0x220 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x455979
RSP: 002b:00007f12c876bc68 EFLAGS: 00000246 ORIG_RAX: 000000000000012b
RAX: ffffffffffffffda RBX: 00007f12c876c6d4 RCX: 0000000000455979
RDX: 000000000000000a RSI: 0000000020007540 RDI: 0000000000000013
RBP: 000000000072bea0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff
R13: 00000000000004e3 R14: 00000000006fb5e8 R15: 0000000000000000

Local variable description: ----addr@___sys_recvmsg
Variable was created at:
 ___sys_recvmsg+0xd5/0x810 net/socket.c:2246
 __sys_recvmmsg+0x58e/0xe30 net/socket.c:2391

Byte 19 of 32 is uninitialized
==================================================================