NetworkPkg/DnsDxe: Fix the potential memory leak issue.

Cc: Ye Ting <ting.ye@intel.com>
Cc: Fu Siyuan <siyuan.fu@intel.com>
Cc: Wang Fan <fan.wang@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Wu Jiaxin <jiaxin.wu@intel.com>
Reviewed-by: Fu Siyuan <siyuan.fu@intel.com>

NetworkPkg/DnsDxe/DnsImpl.c

@@ -792,6 +792,10 @@ UpdateDns4Cache (
         // Delete matching DNS Cache entry
         //
         RemoveEntryList (&Item->AllCacheLink);
+
+        FreePool (Item->DnsCache.HostName);
+        FreePool (Item->DnsCache.IpAddress);
+        FreePool (Item);
         
         return EFI_SUCCESS;
       } else if (Override) {
@@ -819,13 +823,16 @@ UpdateDns4Cache (
    
   NewDnsCache->DnsCache.HostName = AllocatePool (StrSize (DnsCacheEntry.HostName));
   if (NewDnsCache->DnsCache.HostName == NULL) { 
+    FreePool (NewDnsCache);
     return EFI_OUT_OF_RESOURCES;
   }
   
   CopyMem (NewDnsCache->DnsCache.HostName, DnsCacheEntry.HostName, StrSize (DnsCacheEntry.HostName));
 
   NewDnsCache->DnsCache.IpAddress = AllocatePool (sizeof (EFI_IPv4_ADDRESS));
-  if (NewDnsCache->DnsCache.IpAddress == NULL) { 
+  if (NewDnsCache->DnsCache.IpAddress == NULL) {
+    FreePool (NewDnsCache->DnsCache.HostName);
+    FreePool (NewDnsCache);
     return EFI_OUT_OF_RESOURCES;
   }
 
@@ -884,6 +891,10 @@ UpdateDns6Cache (
         //
         RemoveEntryList (&Item->AllCacheLink);
         
+        FreePool (Item->DnsCache.HostName);
+        FreePool (Item->DnsCache.IpAddress);
+        FreePool (Item);
+        
         return EFI_SUCCESS;
       } else if (Override) {
         //
@@ -910,13 +921,16 @@ UpdateDns6Cache (
    
   NewDnsCache->DnsCache.HostName = AllocatePool (StrSize (DnsCacheEntry.HostName));
   if (NewDnsCache->DnsCache.HostName == NULL) { 
+    FreePool (NewDnsCache);
     return EFI_OUT_OF_RESOURCES;
   }
   
   CopyMem (NewDnsCache->DnsCache.HostName, DnsCacheEntry.HostName, StrSize (DnsCacheEntry.HostName));
 
   NewDnsCache->DnsCache.IpAddress = AllocatePool (sizeof (EFI_IPv6_ADDRESS));
-  if (NewDnsCache->DnsCache.IpAddress == NULL) { 
+  if (NewDnsCache->DnsCache.IpAddress == NULL) {
+    FreePool (NewDnsCache->DnsCache.HostName);
+    FreePool (NewDnsCache);
     return EFI_OUT_OF_RESOURCES;
   }
   
@@ -1256,12 +1270,12 @@ ParseDnsResponse (
       //
       // It's the GeneralLookUp querying.
       //
-      Dns4TokenEntry->Token->RspData.GLookupData = AllocatePool (sizeof (DNS_RESOURCE_RECORD));
+      Dns4TokenEntry->Token->RspData.GLookupData = AllocateZeroPool (sizeof (DNS_RESOURCE_RECORD));
       if (Dns4TokenEntry->Token->RspData.GLookupData == NULL) {
         Status = EFI_OUT_OF_RESOURCES;
         goto ON_EXIT;
       }
-      Dns4TokenEntry->Token->RspData.GLookupData->RRList = AllocatePool (DnsHeader->AnswersNum * sizeof (DNS_RESOURCE_RECORD));
+      Dns4TokenEntry->Token->RspData.GLookupData->RRList = AllocateZeroPool (DnsHeader->AnswersNum * sizeof (DNS_RESOURCE_RECORD));
       if (Dns4TokenEntry->Token->RspData.GLookupData->RRList == NULL) {
         Status = EFI_OUT_OF_RESOURCES;
         goto ON_EXIT;
@@ -1271,12 +1285,12 @@ ParseDnsResponse (
       // It's not the GeneralLookUp querying. Check the Query type.
       //
       if (QuerySection->Type == DNS_TYPE_A) {
-        Dns4TokenEntry->Token->RspData.H2AData = AllocatePool (sizeof (DNS_HOST_TO_ADDR_DATA));
+        Dns4TokenEntry->Token->RspData.H2AData = AllocateZeroPool (sizeof (DNS_HOST_TO_ADDR_DATA));
         if (Dns4TokenEntry->Token->RspData.H2AData == NULL) {
           Status = EFI_OUT_OF_RESOURCES;
           goto ON_EXIT;
         }
-        Dns4TokenEntry->Token->RspData.H2AData->IpList = AllocatePool (DnsHeader->AnswersNum * sizeof (EFI_IPv4_ADDRESS));
+        Dns4TokenEntry->Token->RspData.H2AData->IpList = AllocateZeroPool (DnsHeader->AnswersNum * sizeof (EFI_IPv4_ADDRESS));
         if (Dns4TokenEntry->Token->RspData.H2AData->IpList == NULL) {
           Status = EFI_OUT_OF_RESOURCES;
           goto ON_EXIT;
@@ -1293,12 +1307,12 @@ ParseDnsResponse (
       //
       // It's the GeneralLookUp querying.
       //
-      Dns6TokenEntry->Token->RspData.GLookupData = AllocatePool (sizeof (DNS_RESOURCE_RECORD));
+      Dns6TokenEntry->Token->RspData.GLookupData = AllocateZeroPool (sizeof (DNS_RESOURCE_RECORD));
       if (Dns6TokenEntry->Token->RspData.GLookupData == NULL) {
         Status = EFI_OUT_OF_RESOURCES;
         goto ON_EXIT;
       }
-      Dns6TokenEntry->Token->RspData.GLookupData->RRList = AllocatePool (DnsHeader->AnswersNum * sizeof (DNS_RESOURCE_RECORD));
+      Dns6TokenEntry->Token->RspData.GLookupData->RRList = AllocateZeroPool (DnsHeader->AnswersNum * sizeof (DNS_RESOURCE_RECORD));
       if (Dns6TokenEntry->Token->RspData.GLookupData->RRList == NULL) {
         Status = EFI_OUT_OF_RESOURCES;
         goto ON_EXIT;
@@ -1308,12 +1322,12 @@ ParseDnsResponse (
       // It's not the GeneralLookUp querying. Check the Query type.
       //
       if (QuerySection->Type == DNS_TYPE_AAAA) {
-        Dns6TokenEntry->Token->RspData.H2AData = AllocatePool (sizeof (DNS6_HOST_TO_ADDR_DATA));
+        Dns6TokenEntry->Token->RspData.H2AData = AllocateZeroPool (sizeof (DNS6_HOST_TO_ADDR_DATA));
         if (Dns6TokenEntry->Token->RspData.H2AData == NULL) {
           Status = EFI_OUT_OF_RESOURCES;
           goto ON_EXIT;
         }
-        Dns6TokenEntry->Token->RspData.H2AData->IpList = AllocatePool (DnsHeader->AnswersNum * sizeof (EFI_IPv6_ADDRESS));
+        Dns6TokenEntry->Token->RspData.H2AData->IpList = AllocateZeroPool (DnsHeader->AnswersNum * sizeof (EFI_IPv6_ADDRESS));
         if (Dns6TokenEntry->Token->RspData.H2AData->IpList == NULL) {
           Status = EFI_OUT_OF_RESOURCES;
           goto ON_EXIT;
@@ -1603,6 +1617,97 @@ ON_COMPLETE:
   }
 
 ON_EXIT:
+  //
+  // Free the allocated buffer if error happen.
+  //
+  if (EFI_ERROR (Status)) {
+    if (Dns4TokenEntry != NULL) {
+      if (Dns4TokenEntry->GeneralLookUp) {
+        if (Dns4TokenEntry->Token->RspData.GLookupData != NULL) {
+          if (Dns4TokenEntry->Token->RspData.GLookupData->RRList != NULL) {
+            while (RRCount != 0) {
+              RRCount --;
+              if (Dns4TokenEntry->Token->RspData.GLookupData->RRList[RRCount].QName != NULL) {
+                FreePool (Dns4TokenEntry->Token->RspData.GLookupData->RRList[RRCount].QName);
+              }
+
+              if (Dns4TokenEntry->Token->RspData.GLookupData->RRList[RRCount].RData != NULL) {
+                FreePool (Dns4TokenEntry->Token->RspData.GLookupData->RRList[RRCount].RData);
+              }
+            }
+            
+            FreePool (Dns4TokenEntry->Token->RspData.GLookupData->RRList);
+          }
+          
+          FreePool (Dns4TokenEntry->Token->RspData.GLookupData);
+        }
+      } else {
+        if (QuerySection->Type == DNS_TYPE_A && Dns4TokenEntry->Token->RspData.H2AData != NULL) {
+          if (Dns4TokenEntry->Token->RspData.H2AData->IpList != NULL) {
+            FreePool (Dns4TokenEntry->Token->RspData.H2AData->IpList);
+          }
+          
+          FreePool (Dns4TokenEntry->Token->RspData.H2AData);
+        }
+      }
+    }
+
+    if (Dns6TokenEntry != NULL) {
+      if (Dns6TokenEntry->GeneralLookUp) {
+        if (Dns6TokenEntry->Token->RspData.GLookupData != NULL) {
+          if (Dns6TokenEntry->Token->RspData.GLookupData->RRList != NULL) {
+            while (RRCount != 0) {
+              RRCount --;
+              if (Dns6TokenEntry->Token->RspData.GLookupData->RRList[RRCount].QName != NULL) {
+                FreePool (Dns6TokenEntry->Token->RspData.GLookupData->RRList[RRCount].QName);
+              }
+
+              if (Dns6TokenEntry->Token->RspData.GLookupData->RRList[RRCount].RData != NULL) {
+                FreePool (Dns6TokenEntry->Token->RspData.GLookupData->RRList[RRCount].RData);
+              }
+            }
+            
+            FreePool (Dns6TokenEntry->Token->RspData.GLookupData->RRList);
+          }
+          
+          FreePool (Dns6TokenEntry->Token->RspData.GLookupData);
+        }
+      } else {
+        if (QuerySection->Type == DNS_TYPE_AAAA && Dns6TokenEntry->Token->RspData.H2AData != NULL) {
+          if (Dns6TokenEntry->Token->RspData.H2AData->IpList != NULL) {
+            FreePool (Dns6TokenEntry->Token->RspData.H2AData->IpList);
+          }
+          
+          FreePool (Dns6TokenEntry->Token->RspData.H2AData);
+        }
+      }
+    }
+
+    if (Dns4CacheEntry != NULL) {
+      if (Dns4CacheEntry->HostName != NULL) {
+        FreePool (Dns4CacheEntry->HostName);
+      }
+
+      if (Dns4CacheEntry->IpAddress != NULL) {
+        FreePool (Dns4CacheEntry->IpAddress);
+      }
+
+      FreePool (Dns4CacheEntry);
+    }
+
+    if (Dns6CacheEntry != NULL) {
+      if (Dns6CacheEntry->HostName != NULL) {
+        FreePool (Dns6CacheEntry->HostName);
+      }
+
+      if (Dns6CacheEntry->IpAddress != NULL) {
+        FreePool (Dns6CacheEntry->IpAddress);
+      }
+
+      FreePool (Dns6CacheEntry);
+    }    
+  }
+  
   gBS->RestoreTPL (OldTpl);
   return Status;
 }
@@ -2053,6 +2158,9 @@ DnsOnTimerUpdate (
     Item4 = NET_LIST_USER_STRUCT (Entry, DNS4_CACHE, AllCacheLink);
     if (Item4->DnsCache.Timeout == 0) {
       RemoveEntryList (&Item4->AllCacheLink);
+      FreePool (Item4->DnsCache.HostName);
+      FreePool (Item4->DnsCache.IpAddress);
+      FreePool (Item4);
       Entry = mDriverData->Dns4CacheList.ForwardLink;
     } else {
       Entry = Entry->ForwardLink;
@@ -2072,6 +2180,9 @@ DnsOnTimerUpdate (
     Item6 = NET_LIST_USER_STRUCT (Entry, DNS6_CACHE, AllCacheLink);
     if (Item6->DnsCache.Timeout == 0) {
       RemoveEntryList (&Item6->AllCacheLink);
+      FreePool (Item6->DnsCache.HostName);
+      FreePool (Item6->DnsCache.IpAddress);
+      FreePool (Item6);
       Entry = mDriverData->Dns6CacheList.ForwardLink;
     } else {
       Entry = Entry->ForwardLink;