staging/rtl8192u/ieee80211: Fix buffer overflow in ieee80211_softmac_wx.c

Clang/scan-build complains about a possible buffer overflow in
ieee80211_wx_get_name:

.../staging/rtl8192u/ieee80211/ieee80211_softmac_wx.c:499:3:
warning: String copy function overflows destination buffer
	strcat(wrqu->name," link..");

.../staging/rtl8192u/ieee80211/ieee80211_softmac_wx.c:497:3:
warning: String copy function overflows destination buffer
	strcat(wrqu->name," linked");

The buffer wrqu->name is only IFNAMSIZ bytes big (currently 16),
so if we have a "802.11b/g/n linked" device we overrun the buffer by 3
bytes.

-> Use strlcopy / strlcat to populate the name.
This is done in a similar fashion in
staging/rtl8187se/ieee80211/ieee80211_softmac_wx.c

While at it cleaned some whitespace issues.

Signed-off-by: Peter Huewe <peterhuewe@gmx.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/staging/rtl8192u/ieee80211/ieee80211_softmac_wx.c b/drivers/staging/rtl8192u/ieee80211/ieee80211_softmac_wx.c
index 45422db81488f8ddfe848376a55e26be16c9c247..60746b8b1eb0eb7ac6a421a63b154d9351c7ffa9 100644 (file)
--- a/drivers/staging/rtl8192u/ieee80211/ieee80211_softmac_wx.c
+++ b/drivers/staging/rtl8192u/ieee80211/ieee80211_softmac_wx.c
@@ -482,22 +482,23 @@ int ieee80211_wx_get_name(struct ieee80211_device *ieee,
                             struct iw_request_info *info,
                             union iwreq_data *wrqu, char *extra)
 {
-       strcpy(wrqu->name, "802.11");
-       if(ieee->modulation & IEEE80211_CCK_MODULATION){
-               strcat(wrqu->name, "b");
-               if(ieee->modulation & IEEE80211_OFDM_MODULATION)
-                       strcat(wrqu->name, "/g");
-       }else if(ieee->modulation & IEEE80211_OFDM_MODULATION)
-               strcat(wrqu->name, "g");
-       if (ieee->mode & (IEEE_N_24G | IEEE_N_5G))
-               strcat(wrqu->name, "/n");
+       strlcpy(wrqu->name, "802.11", IFNAMSIZ);
+       if (ieee->modulation & IEEE80211_CCK_MODULATION) {
+               strlcat(wrqu->name, "b", IFNAMSIZ);
+               if (ieee->modulation & IEEE80211_OFDM_MODULATION)
+                       strlcat(wrqu->name, "/g", IFNAMSIZ);
+       } else if (ieee->modulation & IEEE80211_OFDM_MODULATION) {
+               strlcat(wrqu->name, "g", IFNAMSIZ);
+       }
 
-       if((ieee->state == IEEE80211_LINKED) ||
-               (ieee->state == IEEE80211_LINKED_SCANNING))
-               strcat(wrqu->name," linked");
-       else if(ieee->state != IEEE80211_NOLINK)
-               strcat(wrqu->name," link..");
+       if (ieee->mode & (IEEE_N_24G | IEEE_N_5G))
+               strlcat(wrqu->name, "/n", IFNAMSIZ);
 
+       if ((ieee->state == IEEE80211_LINKED) ||
+           (ieee->state == IEEE80211_LINKED_SCANNING))
+               strlcat(wrqu->name, " linked", IFNAMSIZ);
+       else if (ieee->state != IEEE80211_NOLINK)
+               strlcat(wrqu->name, " link..", IFNAMSIZ);
 
        return 0;
 }