libiwinfo: fix two segfaults in nl80211 backend

diff --git a/contrib/package/iwinfo/src/iwinfo_nl80211.c b/contrib/package/iwinfo/src/iwinfo_nl80211.c
index 49ddf13..7f27e25 100644 (file)
--- a/contrib/package/iwinfo/src/iwinfo_nl80211.c
+++ b/contrib/package/iwinfo/src/iwinfo_nl80211.c
@@ -136,6 +136,12 @@ static void nl80211_free(struct nl80211_msg_conveyor *cv)
 
        if( cv && cv->msg )
                nlmsg_free(cv->msg);
+
+       if( cv )
+       {
+               cv->cb  = NULL;
+               cv->msg = NULL;
+       }
 }
 
 static struct nl80211_msg_conveyor * nl80211_msg(const char *ifname, int cmd, int flags)
@@ -578,6 +584,7 @@ int nl80211_get_signal(const char *ifname, int *buf)
 
 int nl80211_get_noise(const char *ifname, int *buf)
 {
+       int rv = -1;
        struct nl80211_msg_conveyor *req, *res;
        struct nlattr *si[NL80211_SURVEY_INFO_MAX + 1];
 
@@ -595,10 +602,11 @@ int nl80211_get_noise(const char *ifname, int *buf)
                        if( res->attr[NL80211_ATTR_SURVEY_INFO] )
                        {
                                if( !nla_parse_nested(si, NL80211_SURVEY_INFO_MAX,
-                                               res->attr[NL80211_ATTR_SURVEY_INFO], sp) )
+                                               res->attr[NL80211_ATTR_SURVEY_INFO], sp) &&
+                                       si[NL80211_SURVEY_INFO_NOISE] )
                                {
                                        *buf = (int8_t)nla_get_u8(si[NL80211_SURVEY_INFO_NOISE]);
-                                       return 0;
+                                       rv = 0;
                                }
                        }
                        nl80211_free(res);
@@ -606,7 +614,7 @@ int nl80211_get_noise(const char *ifname, int *buf)
                nl80211_free(req);
        }
 
-       return -1;
+       return rv;
 }
 
 int nl80211_get_quality(const char *ifname, int *buf)