commit c449f10df2d837b7d9d0c46d125e16b277140734
author Mahesh A Saptasagar <c_msapta@qti.qualcomm.com> Fri Jan 09 21:15:18 2015 +0530
committer Satyanarayana Dash <c_sadash@qti.qualcomm.com> Wed Jan 14 17:30:22 2015 +0530
tree 73e23cb94cad5f2815d6e97e79b190b196c5361a
parent 412eaa05dbd4e96437df65d3611964bafbca73e3

wlan: Avoid kernel panic due to invalid memory access

Access to driver data structures during driver load unload,
results in kernel panic.
To mitigate the issue, validate the context before accessing
driver data structures.

Change-Id: I6b7ff681a35d295bd329ce9c2fafa294e73192d9
CRs-Fixed: 779675

CORE/HDD/src/wlan_hdd_hostapd.c

diff --git a/CORE/HDD/src/wlan_hdd_hostapd.c b/CORE/HDD/src/wlan_hdd_hostapd.c
index 9a9eae5..db6bdc5 100644
--- a/CORE/HDD/src/wlan_hdd_hostapd.c
+++ b/CORE/HDD/src/wlan_hdd_hostapd.c
@@ -1740,6 +1740,7 @@
 {
     hdd_adapter_t *pHostapdAdapter = (netdev_priv(dev));
     tHalHandle hHal;
+    hdd_context_t *pHddCtx = NULL;
     int *value = (int *)extra;
     int sub_cmd = value[0];
     int set_value = value[1];
@@ -1747,14 +1748,23 @@
     int ret = 0; /* success */
     v_CONTEXT_t pVosContext;
 
-    if (!pHostapdAdapter || !pHostapdAdapter->pHddCtx)
+    if (NULL == pHostapdAdapter)
     {
         VOS_TRACE(VOS_MODULE_ID_HDD, VOS_TRACE_LEVEL_ERROR,
-                  "%s: either hostapd Adapter is null or HDD ctx is null",
+                  "%s: hostapd Adapter is null",
                   __func__);
         return -1;
     }
 
+    pHddCtx = WLAN_HDD_GET_CTX(pHostapdAdapter);
+    ret = wlan_hdd_validate_context(pHddCtx);
+    if (0 != ret)
+    {
+        hddLog(VOS_TRACE_LEVEL_ERROR,
+               "%s: HDD context is not valid (%d)", __func__, ret);
+        return -1;
+    }
+
     hHal = WLAN_HDD_GET_HAL_CTX(pHostapdAdapter);
     if (!hHal)
     {