1 files changed, 36 insertions, 5 deletions

diff --git a/net/wireless/scan.c b/net/wireless/scan.c
index 2936cb809152..dc23b31594e0 100644
--- a/net/wireless/scan.c
+++ b/net/wireless/scan.c
@@ -12,6 +12,7 @@
 #include <linux/etherdevice.h>
 #include <net/arp.h>
 #include <net/cfg80211.h>
+#include <net/cfg80211-wext.h>
 #include <net/iw_handler.h>
 #include "core.h"
 #include "nl80211.h"
@@ -227,21 +228,51 @@ const u8 *cfg80211_find_ie(u8 eid, const u8 *ies, int len)
 }
 EXPORT_SYMBOL(cfg80211_find_ie);
 
+const u8 *cfg80211_find_vendor_ie(unsigned int oui, u8 oui_type,
+                                  const u8 *ies, int len)
+{
+        struct ieee80211_vendor_ie *ie;
+        const u8 *pos = ies, *end = ies + len;
+        int ie_oui;
+
+        while (pos < end) {
+                pos = cfg80211_find_ie(WLAN_EID_VENDOR_SPECIFIC, pos,
+                                       end - pos);
+                if (!pos)
+                        return NULL;
+
+                if (end - pos < sizeof(*ie))
+                        return NULL;
+
+                ie = (struct ieee80211_vendor_ie *)pos;
+                ie_oui = ie->oui[0] << 16 | ie->oui[1] << 8 | ie->oui[2];
+                if (ie_oui == oui && ie->oui_type == oui_type)
+                        return pos;
+
+                pos += 2 + ie->len;
+        }
+        return NULL;
+}
+EXPORT_SYMBOL(cfg80211_find_vendor_ie);
+
 static int cmp_ies(u8 num, u8 *ies1, size_t len1, u8 *ies2, size_t len2)
 {
         const u8 *ie1 = cfg80211_find_ie(num, ies1, len1);
         const u8 *ie2 = cfg80211_find_ie(num, ies2, len2);
-        int r;
 
+        /* equal if both missing */
         if (!ie1 && !ie2)
                 return 0;
-        if (!ie1 || !ie2)
+        /* sort missing IE before (left of) present IE */
+        if (!ie1)
                 return -1;
+        if (!ie2)
+                return 1;
 
-        r = memcmp(ie1 + 2, ie2 + 2, min(ie1[1], ie2[1]));
-        if (r == 0 && ie1[1] != ie2[1])
+        /* sort by length first, then by contents */
+        if (ie1[1] != ie2[1])
                 return ie2[1] - ie1[1];
-        return r;
+        return memcmp(ie1 + 2, ie2 + 2, ie1[1]);
 }
 
 static bool is_bss(struct cfg80211_bss *a,