ShellPkg: acpiview: MADT: Validate global pointers before use

Check if the MadtInterruptControllerType and
MadtInterruptControllerLength pointers have been successfully updated
before they are used for further table parsing.

Signed-off-by: Krzysztof Koch <krzysztof.koch@arm.com>

1 files changed, 13 insertions, 0 deletions

diff --git a/ShellPkg/Library/UefiShellAcpiViewCommandLib/Parsers/Madt/MadtParser.c b/ShellPkg/Library/UefiShellAcpiViewCommandLib/Parsers/Madt/MadtParser.c
index 90bdafea19..438905cb24 100644
--- a/ShellPkg/Library/UefiShellAcpiViewCommandLib/Parsers/Madt/MadtParser.c
+++ b/ShellPkg/Library/UefiShellAcpiViewCommandLib/Parsers/Madt/MadtParser.c
@@ -260,6 +260,19 @@ ParseAcpiMadt (
       PARSER_PARAMS (MadtInterruptControllerHeaderParser)

       );

 

+    // Check if the values used to control the parsing logic have been

+    // successfully read.

+    if ((MadtInterruptControllerType == NULL) ||

+        (MadtInterruptControllerLength == NULL)) {

+      IncrementErrorCount ();

+      Print (

+        L"ERROR: Insufficient remaining table buffer length to read the " \

+          L"Interrupt Controller Structure header. Length = %d.\n",

+        AcpiTableLength - Offset

+        );

+      return;

+    }

+

     // Make sure forward progress is made.

     if (*MadtInterruptControllerLength < 2) {

       IncrementErrorCount ();