Merge branch 'drm-armada-fixes' of git://git.armlinux.org.uk/~rmk/linux-arm into...

[cascardo/linux.git] / net / wireless / scan.c

diff --git a/net/wireless/scan.c b/net/wireless/scan.c
index 0358e12..b5bd58d 100644 (file)
--- a/net/wireless/scan.c
+++ b/net/wireless/scan.c
@@ -352,52 +352,48 @@ void cfg80211_bss_expire(struct cfg80211_registered_device *rdev)
        __cfg80211_bss_expire(rdev, jiffies - IEEE80211_SCAN_RESULT_EXPIRE);
 }
 
-const u8 *cfg80211_find_ie(u8 eid, const u8 *ies, int len)
+const u8 *cfg80211_find_ie_match(u8 eid, const u8 *ies, int len,
+                                const u8 *match, int match_len,
+                                int match_offset)
 {
-       while (len > 2 && ies[0] != eid) {
+       /* match_offset can't be smaller than 2, unless match_len is
+        * zero, in which case match_offset must be zero as well.
+        */
+       if (WARN_ON((match_len && match_offset < 2) ||
+                   (!match_len && match_offset)))
+               return NULL;
+
+       while (len >= 2 && len >= ies[1] + 2) {
+               if ((ies[0] == eid) &&
+                   (ies[1] + 2 >= match_offset + match_len) &&
+                   !memcmp(ies + match_offset, match, match_len))
+                       return ies;
+
                len -= ies[1] + 2;
                ies += ies[1] + 2;
        }
-       if (len < 2)
-               return NULL;
-       if (len < 2 + ies[1])
-               return NULL;
-       return ies;
+
+       return NULL;
 }
-EXPORT_SYMBOL(cfg80211_find_ie);
+EXPORT_SYMBOL(cfg80211_find_ie_match);
 
 const u8 *cfg80211_find_vendor_ie(unsigned int oui, int oui_type,
                                  const u8 *ies, int len)
 {
-       struct ieee80211_vendor_ie *ie;
-       const u8 *pos = ies, *end = ies + len;
-       int ie_oui;
+       const u8 *ie;
+       u8 match[] = { oui >> 16, oui >> 8, oui, oui_type };
+       int match_len = (oui_type < 0) ? 3 : sizeof(match);
 
        if (WARN_ON(oui_type > 0xff))
                return NULL;
 
-       while (pos < end) {
-               pos = cfg80211_find_ie(WLAN_EID_VENDOR_SPECIFIC, pos,
-                                      end - pos);
-               if (!pos)
-                       return NULL;
-
-               ie = (struct ieee80211_vendor_ie *)pos;
-
-               /* make sure we can access ie->len */
-               BUILD_BUG_ON(offsetof(struct ieee80211_vendor_ie, len) != 1);
+       ie = cfg80211_find_ie_match(WLAN_EID_VENDOR_SPECIFIC, ies, len,
+                                   match, match_len, 2);
 
-               if (ie->len < sizeof(*ie))
-                       goto cont;
+       if (ie && (ie[1] < 4))
+               return NULL;
 
-               ie_oui = ie->oui[0] << 16 | ie->oui[1] << 8 | ie->oui[2];
-               if (ie_oui == oui &&
-                   (oui_type < 0 || ie->oui_type == oui_type))
-                       return pos;
-cont:
-               pos += 2 + ie->len;
-       }
-       return NULL;
+       return ie;
 }
 EXPORT_SYMBOL(cfg80211_find_vendor_ie);