NetworkPkg: PxeBcDhcp6GoogleTest: Fix Stack Smashing Unit Test

PxeBcDhcp6GoogleTest's MultipleDnsEntries test started to fail
with stack cookies added for host applications. Debugging this
showed that the test was attempting to copy two UINT16s to a
UINT8 Data[1] array allocated on the stack. This was moved to
a heap based allocation for a UINT32 to accommodate the proper
size. After this fix, the unit test passed with stack cookies
enabled.

Signed-off-by: Oliver Smith-Denny <osde@linux.microsoft.com>

diff --git a/NetworkPkg/UefiPxeBcDxe/GoogleTest/PxeBcDhcp6GoogleTest.cpp b/NetworkPkg/UefiPxeBcDxe/GoogleTest/PxeBcDhcp6GoogleTest.cpp
index 61736ff79e83fe5d62785e9d1bbae82dd9cc7505..e529bc6daf1d5c79713841ec2b6c243782222dc9 100644 (file)
--- a/NetworkPkg/UefiPxeBcDxe/GoogleTest/PxeBcDhcp6GoogleTest.cpp
+++ b/NetworkPkg/UefiPxeBcDxe/GoogleTest/PxeBcDhcp6GoogleTest.cpp
@@ -290,15 +290,9 @@ TEST_F (PxeBcCacheDnsServerAddressesTest, AttemptUnderflowTest) {
 // Test Description\r
 // Test that we can handle recursive dns (multiple dns entries)\r
 TEST_F (PxeBcCacheDnsServerAddressesTest, MultipleDnsEntries) {\r
-  EFI_DHCP6_PACKET_OPTION   Option  = { 0 };\r
+  EFI_DHCP6_PACKET_OPTION   *Option = NULL;\r
   PXEBC_DHCP6_PACKET_CACHE  *Cache6 = NULL;\r
 \r
-  Private.SelectIndex                         = 1; // SelectIndex is 1-based\r
-  Cache6                                      = &Private.OfferBuffer[Private.SelectIndex - 1].Dhcp6;\r
-  Cache6->OptList[PXEBC_DHCP6_IDX_DNS_SERVER] = &Option;\r
-  // Setup the DHCPv6 offer packet\r
-  Cache6->OptList[PXEBC_DHCP6_IDX_DNS_SERVER]->OpCode = DHCP6_OPT_SERVER_ID;\r
-\r
   EFI_IPv6_ADDRESS  addresses[2] = {\r
     // 2001:db8:85a3::8a2e:370:7334\r
     { 0x20, 0x01, 0x0d, 0xb8, 0x85, 0xa3, 0x00, 0x00, 0x00, 0x00, 0x8a, 0x2e, 0x03, 0x70, 0x73, 0x34 },\r
@@ -306,7 +300,18 @@ TEST_F (PxeBcCacheDnsServerAddressesTest, MultipleDnsEntries) {
     { 0xfe, 0x80, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xd4, 0x78, 0x91, 0xc3, 0xec, 0xd7, 0x4f, 0xf9 }\r
   };\r
 \r
-  CopyMem (Cache6->OptList[PXEBC_DHCP6_IDX_DNS_SERVER]->Data, &addresses, sizeof (addresses));\r
+  Option = (EFI_DHCP6_PACKET_OPTION *)AllocatePool (sizeof (*Option) + sizeof (addresses));\r
+  if (Option == NULL) {\r
+    ASSERT_NE (Option, nullptr);\r
+  }\r
+\r
+  Private.SelectIndex                         = 1; // SelectIndex is 1-based\r
+  Cache6                                      = &Private.OfferBuffer[Private.SelectIndex - 1].Dhcp6;\r
+  Cache6->OptList[PXEBC_DHCP6_IDX_DNS_SERVER] = Option;\r
+  // Setup the DHCPv6 offer packet\r
+  Cache6->OptList[PXEBC_DHCP6_IDX_DNS_SERVER]->OpCode = DHCP6_OPT_SERVER_ID;\r
+\r
+  CopyMem (Cache6->OptList[PXEBC_DHCP6_IDX_DNS_SERVER]->Data, addresses, sizeof (addresses));\r
 \r
   Cache6->OptList[PXEBC_DHCP6_IDX_DNS_SERVER]->OpLen = NTOHS (sizeof (addresses));\r
 \r
@@ -327,6 +332,10 @@ TEST_F (PxeBcCacheDnsServerAddressesTest, MultipleDnsEntries) {
   if (Private.DnsServer) {\r
     FreePool (Private.DnsServer);\r
   }\r
+\r
+  if (Option) {\r
+    FreePool (Option);\r
+  }\r
 }\r
 \r
 ///////////////////////////////////////////////////////////////////////////////\r