MdeModulePkg:Fix a robustness issue of Mnp Driver

v3:
*
When there exists duplicate items in VLAN variable , save the correct
variable content back to the variable storage after duplicate items are removed

Duplicate items in VLAN variable will cause MNP driver binding
start function fall into infinite loop,so we should check it's
content before using it.

Cc: Fu Siyuan <siyuan.fu@intel.com>
Cc: Ye Ting <ting.ye@intel.com>
Cc: Wu Jiaxin <jiaxin.wu@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Zhang Lubo <lubo.zhang@intel.com>
Reviewed-by: Ye Ting <ting.ye@intel.com>
Reviewed-by: Fu Siyuan <siyuan.fu@intel.com>
Reviewed-by: Wu Jiaxin <jiaxin.wu@intel.com>

diff --git a/MdeModulePkg/Universal/Network/MnpDxe/MnpVlan.c b/MdeModulePkg/Universal/Network/MnpDxe/MnpVlan.c
index 6e14c1f37f3f8b07dfc850e36e62b5bdaf6ad386..98cbc2e35da85c906f15c8d1ec29429b72f7063f 100644 (file)
--- a/MdeModulePkg/Universal/Network/MnpDxe/MnpVlan.c
+++ b/MdeModulePkg/Universal/Network/MnpDxe/MnpVlan.c
@@ -1,7 +1,7 @@
 /** @file\r
   VLAN Config Protocol implementation and VLAN packet process routine.\r
 \r
-Copyright (c) 2009 - 2014, Intel Corporation. All rights reserved.<BR>\r
+Copyright (c) 2009 - 2016, Intel Corporation. All rights reserved.<BR>\r
 This program and the accompanying materials\r
 are licensed and made available under the terms and conditions\r
 of the BSD License which accompanies this distribution.  The full\r
@@ -230,6 +230,59 @@ MnpInsertVlanTag (
   VlanTci->Uint16        = HTONS (VlanTci->Uint16);\r
 }\r
 \r
+/**\r
+  Check VLAN configuration variable and delete the duplicative content if has identical Vlan ID.\r
+\r
+  @param[in]      MnpDeviceData      Pointer to the MNP device context data.\r
+  @param[in]      Buffer             Pointer to the buffer contains the array of VLAN_TCI.\r
+  @param[in]      NumberOfVlan       Pointer to number of VLAN.\r
+  @param[out]     NewNumberOfVlan    Pointer to number of unique VLAN.\r
+  \r
+  @retval EFI_SUCCESS            The VLAN variable is successfully checked.\r
+  @retval EFI_OUT_OF_RESOURCES   There is not enough resource to set the configuration.\r
+\r
+**/\r
+EFI_STATUS\r
+MnpCheckVlanVariable (\r
+  IN     MNP_DEVICE_DATA   *MnpDeviceData,\r
+  IN     VLAN_TCI          *Buffer,\r
+  IN     UINTN             NumberOfVlan,\r
+     OUT UINTN             *NewNumberOfVlan\r
+  )\r
+{\r
+  UINTN             Index;\r
+  UINTN             Index2;\r
+  UINTN             Count;\r
+  BOOLEAN           FoundDuplicateItem;\r
+  EFI_STATUS        Status;\r
+\r
+  Count = 0;\r
+  FoundDuplicateItem  = FALSE;\r
+  Status = EFI_SUCCESS;\r
+  \r
+  for (Index = 0; Index < NumberOfVlan; Index++) {\r
+   for (Index2 = Index + 1; Index2 < NumberOfVlan; Index2++) {\r
+     if (Buffer[Index].Bits.Vid == Buffer[Index2].Bits.Vid) {\r
+       FoundDuplicateItem = TRUE;\r
+       Count++;\r
+       break;\r
+     }\r
+   }\r
+   if (FoundDuplicateItem) {\r
+    for (Index2 = Index +1; Index2 < NumberOfVlan; Index++, Index2++) {\r
+      CopyMem (Buffer + Index, Buffer + Index2, sizeof (VLAN_TCI));\r
+    }\r
+   }\r
+   FoundDuplicateItem = FALSE;\r
+  }\r
+\r
+  *NewNumberOfVlan = NumberOfVlan - Count;\r
+  if (Count != 0) {\r
+    Status = MnpSetVlanVariable (MnpDeviceData, *NewNumberOfVlan, Buffer);\r
+  }\r
+  \r
+  return Status;\r
+}\r
 \r
 /**\r
   Get VLAN configuration variable.\r
@@ -255,6 +308,7 @@ MnpGetVlanVariable (
   UINTN       BufferSize;\r
   EFI_STATUS  Status;\r
   VLAN_TCI    *Buffer;\r
+  UINTN       NewNumberOfVlan;\r
 \r
   //\r
   // Get VLAN configuration from EFI Variable\r
@@ -292,13 +346,15 @@ MnpGetVlanVariable (
     return Status;\r
   }\r
 \r
-  *NumberOfVlan = BufferSize / sizeof (VLAN_TCI);\r
-  *VlanVariable = Buffer;\r
+  Status = MnpCheckVlanVariable (MnpDeviceData, Buffer, BufferSize / sizeof (VLAN_TCI), &NewNumberOfVlan);\r
+  if (!EFI_ERROR (Status)) {\r
+    *NumberOfVlan = NewNumberOfVlan;\r
+    *VlanVariable = Buffer;\r
+  }\r
 \r
   return Status;\r
 }\r
 \r
-\r
 /**\r
   Set VLAN configuration variable.\r
 \r