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-rw-r--r--src/VBox/Devices/EFI/Firmware/MdePkg/Library/BaseStackCheckLib/BaseStackCheckGcc.c49
1 files changed, 49 insertions, 0 deletions
diff --git a/src/VBox/Devices/EFI/Firmware/MdePkg/Library/BaseStackCheckLib/BaseStackCheckGcc.c b/src/VBox/Devices/EFI/Firmware/MdePkg/Library/BaseStackCheckLib/BaseStackCheckGcc.c
new file mode 100644
index 00000000..af8664b5
--- /dev/null
+++ b/src/VBox/Devices/EFI/Firmware/MdePkg/Library/BaseStackCheckLib/BaseStackCheckGcc.c
@@ -0,0 +1,49 @@
+/** @file
+ Base Stack Check library for GCC/clang.
+
+ Use -fstack-protector-all compiler flag to make the compiler insert the
+ __stack_chk_guard "canary" value into the stack and check the value prior
+ to exiting the function. If the "canary" is overwritten __stack_chk_fail()
+ is called. This is GCC specific code.
+
+ Copyright (c) 2012, Apple Inc. All rights reserved.<BR>
+ SPDX-License-Identifier: BSD-2-Clause-Patent
+
+**/
+
+#include <Base.h>
+#include <Library/BaseLib.h>
+#include <Library/DebugLib.h>
+#include <Library/PcdLib.h>
+
+/// "canary" value that is inserted by the compiler into the stack frame.
+VOID *__stack_chk_guard = (VOID*)0x0AFF;
+
+// If ASLR was enabled we could use
+//void (*__stack_chk_guard)(void) = __stack_chk_fail;
+
+/**
+ Error path for compiler generated stack "canary" value check code. If the
+ stack canary has been overwritten this function gets called on exit of the
+ function.
+**/
+VOID
+__stack_chk_fail (
+ VOID
+ )
+{
+ UINT8 DebugPropertyMask;
+
+ DEBUG ((DEBUG_ERROR, "STACK FAULT: Buffer Overflow in function %a.\n", __builtin_return_address(0)));
+
+ //
+ // Generate a Breakpoint, DeadLoop, or NOP based on PCD settings even if
+ // BaseDebugLibNull is in use.
+ //
+ DebugPropertyMask = PcdGet8 (PcdDebugPropertyMask);
+ if ((DebugPropertyMask & DEBUG_PROPERTY_ASSERT_BREAKPOINT_ENABLED) != 0) {
+ CpuBreakpoint ();
+ } else if ((DebugPropertyMask & DEBUG_PROPERTY_ASSERT_DEADLOOP_ENABLED) != 0) {
+ CpuDeadLoop ();
+ }
+}