extensions: libxt_connlabel: fix crash when connlabel.conf is empty

When connlabel.conf is empty, nfct_labelmap_new will return NULL and
set errno to 0. So we will miss to check this situation, and cause NULL
deference in nfct_labelmap_get_bit.

Input the following commands will reproduce this crash:
  # echo > /etc/xtables/connlabel.conf
  # iptables -A INPUT -m connlabel --label abc
  Segmentation fault (core dumped)

Signed-off-by: Liping Zhang <liping.zhang@spreadtrum.com>
Signed-off-by: Florian Westphal <fw@strlen.de>

0 files changed, 0 insertions, 0 deletions