Re: KMSAN: uninit-value in strcmp

From: David Miller
Date: Thu May 03 2018 - 15:22:22 EST


From: syzbot <syzbot+df0257c92ffd4fcc58cd@xxxxxxxxxxxxxxxxxxxxxxxxx>
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.