From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: KMSAN: uninit-value in strcmp
Date: Thu, 03 May 2018 15:22:13 -0400 (EDT)
Message-ID: <20180503.152213.740988890883315228.davem@davemloft.net>
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From: syzbot <syzbot+df0257c92ffd4fcc58cd@syzkaller.appspotmail.com>
Date: Thu, 03 May 2018 11:44:02 -0700

> 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
>  strcmp+0xf7/0x160 lib/string.c:329
>  tipc_nl_node_get_link+0x220/0x6f0 net/tipc/node.c:1881
>  genl_family_rcv_msg net/netlink/genetlink.c:599 [inline]

Hmmm, TIPC_NL_LINK_GET uses tipc_nl_policy, which has a proper nesting
entry for TIPC_NLA_LINK.  I wonder how the code goes about validating
TIPC_NLA_LINK_NAME in such a case?  Does it?

This may be the problem.