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BUG: KMSAN: uninit-value in do_error_trap+0x39b/0x600 arch/x86/kernel/traps.c:297
CPU: 1 PID: 6628 Comm: syz-executor6 Not tainted 4.17.0-rc3+ #90
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
 __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+0x14/0x20 arch/x86/entry/entry_64.S:992
RIP: 0010:kmsan_copy_to_user+0x141/0x160 mm/kmsan/kmsan.c:1213
RSP: 0018:ffff880144aff988 EFLAGS: 00010206
RAX: ffff880144ac8000 RBX: ffff880144affb20 RCX: 000000000000000c
RDX: 00007ffffffff000 RSI: ffff880144affb20 RDI: ffe7001200000012
RBP: ffff880144aff9d0 R08: 0000000001080020 R09: ffff8801445efa44
R10: 0000000000000000 R11: 0000000000000000 R12: 000000000000000c
R13: ffe7001200000012 R14: 0000000000000000 R15: 00000000d1c000c3
 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+0x2a6/0x3e0 net/socket.c:2472
 __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:00007f3daf6a8c68 EFLAGS: 00000246 ORIG_RAX: 000000000000012b
RAX: ffffffffffffffda RBX: 00007f3daf6a96d4 RCX: 0000000000455979
RDX: 000000000400038b RSI: 00000000200000c0 RDI: 0000000000000013
RBP: 000000000072bea0 R08: 0000000020000340 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff
R13: 0000000000000548 R14: 00000000006fbf60 R15: 0000000000000000

Local variable description: ----ucreds.i@netlink_recvmsg
Variable was created at:
 netlink_recvmsg+0xe8/0x1900 net/netlink/af_netlink.c:1910
 sock_recvmsg_nosec net/socket.c:802 [inline]
 sock_recvmsg+0x1d0/0x230 net/socket.c:809
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