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BUG: KMSAN: uninit-value in do_error_trap+0x39b/0x600 arch/x86/kernel/traps.c:297
CPU: 1 PID: 4499 Comm: syz-executor439 Not tainted 4.16.0+ #87
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0x185/0x1d0 lib/dump_stack.c:53
 kmsan_report+0x142/0x240 mm/kmsan/kmsan.c:1067
 __msan_warning_32+0x6c/0xb0 mm/kmsan/kmsan_instr.c:683
 do_error_trap+0x39b/0x600 arch/x86/kernel/traps.c:297
 do_invalid_op+0x46/0x50 arch/x86/kernel/traps.c:316
 invalid_op+0x1b/0x40 arch/x86/entry/entry_64.S:986
RIP: 0010:kmsan_copy_to_user+0x141/0x160 mm/kmsan/kmsan.c:1213
RSP: 0018:ffff88019944f968 EFLAGS: 00010206
RAX: ffff8801cf2a9d80 RBX: ffff88019944fb00 RCX: 000000000000000a
RDX: 00007ffffffff000 RSI: ffff88019944fb00 RDI: 656c69662f2e0001
RBP: ffff88019944f9b0 R08: 0000000001080020 R09: ffff8801cbe6fa24
R10: ffff8801cb309800 R11: 000000018010000e R12: 000000000000000a
R13: 656c69662f2e0001 R14: 0000000000000000 R15: 0000000099200094
 copy_to_user include/linux/uaccess.h:184 [inline]
 move_addr_to_user+0x32e/0x530 net/socket.c:227
 ___sys_recvmsg+0x4e2/0x810 net/socket.c:2211
 __sys_recvmmsg+0x54e/0xdb0 net/socket.c:2313
 SYSC_recvmmsg+0x212/0x3e0 net/socket.c:2389
 SyS_recvmmsg+0x76/0xa0 net/socket.c:2378
 do_syscall_64+0x309/0x430 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x3d/0xa2
RIP: 0033:0x4455f9
RSP: 002b:00007f80cedcbdb8 EFLAGS: 00000246 ORIG_RAX: 000000000000012b
RAX: ffffffffffffffda RBX: 00000000006dac24 RCX: 00000000004455f9
RDX: 0000000000000379 RSI: 0000000020000000 RDI: 0000000000000003
RBP: 00000000006dac20 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffd43a4c2bf R14: 00007f80cedcc9c0 R15: 0000000000000001

Local variable description: ----timeout@futex_wait
Variable was created at:
 futex_wait+0xde/0xc20 kernel/futex.c:2613
 do_futex+0x284a/0x6ad0 kernel/futex.c:3527
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