prima: Add buf len check in wlan_hdd_cfg80211_testmode

In __wlan_hdd_cfg80211_testmode API no checks are in place that
ensure that buflen is smaller or equal the size of the stack
variable hb_params. Hence, the vos_mem_copy() call can overflow
stack memory.

Add buf len check to avoid stack overflow

CRs-Fixed: 1105085
Change-Id: I6af6a74cc38ebce3337120adcf7e9595f22d3d8c

drivers/staging/prima/CORE/HDD/src/wlan_hdd_cfg80211.c

@@ -16579,6 +16579,12 @@ static int __wlan_hdd_cfg80211_testmode(struct wiphy *wiphy, void *data, int len
                 (hb_params_temp->params.lphbTcpParamReq.timePeriodSec == 0))
                 return -EINVAL;
 
+            if (buf_len > sizeof(*hb_params)) {
+                hddLog(LOGE, FL("buf_len=%d exceeded hb_params size limit"),
+                       buf_len);
+                return -ERANGE;
+            }
+
             hb_params = (tSirLPHBReq *)vos_mem_malloc(sizeof(tSirLPHBReq));
             if (NULL == hb_params)
             {