diff --git a/MdeModulePkg/Include/Library/NetLib.h b/MdeModulePkg/Include/Library/NetLib.h
index ba352dea60..c9715012a7 100644
--- a/MdeModulePkg/Include/Library/NetLib.h
+++ b/MdeModulePkg/Include/Library/NetLib.h
@@ -215,7 +215,7 @@ Ip4IsUnicast (
   IN IP4_ADDR               NetMask
   );
 
-extern IP4_ADDR mIp4AllMasks [IP4_MASK_NUM];
+extern IP4_ADDR gIp4AllMasks [IP4_MASK_NUM];
 
 
 extern EFI_IPv4_ADDRESS  mZeroIp4Addr;
diff --git a/MdeModulePkg/Library/DxeCrc32GuidedSectionExtractLib/DxeCrc32GuidedSectionExtractLib.c b/MdeModulePkg/Library/DxeCrc32GuidedSectionExtractLib/DxeCrc32GuidedSectionExtractLib.c
index 99f7285108..7271108c40 100644
--- a/MdeModulePkg/Library/DxeCrc32GuidedSectionExtractLib/DxeCrc32GuidedSectionExtractLib.c
+++ b/MdeModulePkg/Library/DxeCrc32GuidedSectionExtractLib/DxeCrc32GuidedSectionExtractLib.c
@@ -22,6 +22,8 @@ WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
 #include <Library/BaseMemoryLib.h>
 #include <Library/UefiBootServicesTableLib.h>
 
+#define EFI_SECITON_SIZE_MASK 0x00ffffff
+
 typedef struct {
   EFI_GUID_DEFINED_SECTION  GuidedSectionHeader;
   UINT32                    CRC32Checksum;
@@ -64,7 +66,7 @@ Crc32GuidedSectionGetInfo (
   //
   *SectionAttribute  = ((EFI_GUID_DEFINED_SECTION *) InputSection)->Attributes;
   *ScratchBufferSize = 0;
-  *OutputBufferSize  = *(UINT32 *) (((EFI_COMMON_SECTION_HEADER *) InputSection)->Size) & 0x00ffffff;
+  *OutputBufferSize  = *(UINT32 *) (((EFI_COMMON_SECTION_HEADER *) InputSection)->Size) & EFI_SECITON_SIZE_MASK;
   *OutputBufferSize  -= ((EFI_GUID_DEFINED_SECTION *) InputSection)->DataOffset;
 
   return EFI_SUCCESS;
@@ -117,7 +119,7 @@ Crc32GuidedSectionHandler (
   //
   Crc32SectionHeader = (CRC32_SECTION_HEADER *) InputSection;
   *OutputBuffer      = (UINT8 *) InputSection + Crc32SectionHeader->GuidedSectionHeader.DataOffset;
-  OutputBufferSize   = *(UINT32 *) (((EFI_COMMON_SECTION_HEADER *) InputSection)->Size) & 0x00ffffff; 
+  OutputBufferSize   = *(UINT32 *) (((EFI_COMMON_SECTION_HEADER *) InputSection)->Size) & EFI_SECITON_SIZE_MASK; 
   OutputBufferSize   -= Crc32SectionHeader->GuidedSectionHeader.DataOffset;
 
   //
diff --git a/MdeModulePkg/Library/DxeNetLib/DxeNetLib.c b/MdeModulePkg/Library/DxeNetLib/DxeNetLib.c
index bf1a969821..a3ea083b51 100644
--- a/MdeModulePkg/Library/DxeNetLib/DxeNetLib.c
+++ b/MdeModulePkg/Library/DxeNetLib/DxeNetLib.c
@@ -43,7 +43,7 @@ EFI_DPC_PROTOCOL *mDpc = NULL;
 //
 // All the supported IP4 maskes in host byte order.
 //
-IP4_ADDR  mIp4AllMasks[IP4_MASK_NUM] = {
+IP4_ADDR  gIp4AllMasks[IP4_MASK_NUM] = {
   0x00000000,
   0x80000000,
   0xC0000000,
@@ -104,7 +104,7 @@ NetGetMaskLength (
   INTN                      Index;
 
   for (Index = 0; Index < IP4_MASK_NUM; Index++) {
-    if (NetMask == mIp4AllMasks[Index]) {
+    if (NetMask == gIp4AllMasks[Index]) {
       break;
     }
   }
@@ -179,7 +179,7 @@ Ip4IsUnicast (
   }
 
   if (NetMask == 0) {
-    NetMask = mIp4AllMasks[Class << 3];
+    NetMask = gIp4AllMasks[Class << 3];
   }
 
   if (((Ip &~NetMask) == ~NetMask) || ((Ip &~NetMask) == 0)) {
diff --git a/MdeModulePkg/Universal/Network/Dhcp4Dxe/Dhcp4Io.c b/MdeModulePkg/Universal/Network/Dhcp4Dxe/Dhcp4Io.c
index 1f168c6dff..b09eb4f5f3 100644
--- a/MdeModulePkg/Universal/Network/Dhcp4Dxe/Dhcp4Io.c
+++ b/MdeModulePkg/Universal/Network/Dhcp4Dxe/Dhcp4Io.c
@@ -409,7 +409,7 @@ DhcpLeaseAcquired (
 
   if (DhcpSb->Netmask == 0) {
     Class           = NetGetIpClass (DhcpSb->ClientAddr);
-    DhcpSb->Netmask = mIp4AllMasks[Class << 3];
+    DhcpSb->Netmask = gIp4AllMasks[Class << 3];
   }
 
   if (DhcpSb->LeaseIoPort != NULL) {
diff --git a/MdeModulePkg/Universal/Network/Ip4Dxe/Ip4If.c b/MdeModulePkg/Universal/Network/Ip4Dxe/Ip4If.c
index d8f88e14b1..5e121a5dcf 100644
--- a/MdeModulePkg/Universal/Network/Ip4Dxe/Ip4If.c
+++ b/MdeModulePkg/Universal/Network/Ip4Dxe/Ip4If.c
@@ -554,7 +554,7 @@ Ip4SetAddress (
 
   Type                      = NetGetIpClass (IpAddr);
   Len                       = NetGetMaskLength (SubnetMask);
-  Netmask                   = mIp4AllMasks[MIN (Len, Type << 3)];
+  Netmask                   = gIp4AllMasks[MIN (Len, Type << 3)];
   Interface->NetBrdcast     = (IpAddr | ~Netmask);
 
   //
diff --git a/MdeModulePkg/Universal/Network/Ip4Dxe/Ip4Impl.c b/MdeModulePkg/Universal/Network/Ip4Dxe/Ip4Impl.c
index d1302acaa3..ce546c235d 100644
--- a/MdeModulePkg/Universal/Network/Ip4Dxe/Ip4Impl.c
+++ b/MdeModulePkg/Universal/Network/Ip4Dxe/Ip4Impl.c
@@ -796,7 +796,7 @@ Ip4StationAddressValid (
     return FALSE;
   }
 
-  NetBrdcastMask = mIp4AllMasks[MIN (Len, Type << 3)];
+  NetBrdcastMask = gIp4AllMasks[MIN (Len, Type << 3)];
 
   if (Ip == (Ip | ~NetBrdcastMask)) {
     return FALSE;