Revision: 19710
          http://sourceforge.net/p/edk2/code/19710
Author:   lersek
Date:     2016-01-21 18:40:09 +0000 (Thu, 21 Jan 2016)
Log Message:
-----------
ShellPkg: BcfgDisplayDump(): enforce minimum size for Boot#### and co.

"3.1.1 Boot Manager Programming" in the UEFI 2.5 spec mandates that
Boot#### and similar options contain EFI_LOAD_OPTION structures. The
EFI_LOAD_OPTION structure encodes the fixed initial part of the payload,
and we can (and should) use it to enforce a minimum size for variable
contents.

This patch is meant as a safety improvement.

Cc: Jaben Carsey <[email protected]>
Cc: Ryan Harkin <[email protected]>
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Laszlo Ersek <[email protected]>
Reviewed-by: Jaben Carsey <[email protected]>

Modified Paths:
--------------
    
trunk/edk2/ShellPkg/Library/UefiShellBcfgCommandLib/UefiShellBcfgCommandLib.c
    
trunk/edk2/ShellPkg/Library/UefiShellBcfgCommandLib/UefiShellBcfgCommandLib.uni

Modified: 
trunk/edk2/ShellPkg/Library/UefiShellBcfgCommandLib/UefiShellBcfgCommandLib.c
===================================================================
--- 
trunk/edk2/ShellPkg/Library/UefiShellBcfgCommandLib/UefiShellBcfgCommandLib.c   
    2016-01-21 18:40:05 UTC (rev 19709)
+++ 
trunk/edk2/ShellPkg/Library/UefiShellBcfgCommandLib/UefiShellBcfgCommandLib.c   
    2016-01-21 18:40:09 UTC (rev 19710)
@@ -1052,6 +1052,7 @@
   CHAR16          *DevPathString;
   VOID            *DevPath;
   UINTN           Errors;
+  EFI_LOAD_OPTION *LoadOption;
 
   if (OrderCount == 0) {
     ShellPrintHiiEx(-1, -1, NULL, STRING_TOKEN(STR_BCFG_NONE), 
gShellBcfgHiiHandle, L"bcfg");  
@@ -1090,6 +1091,24 @@
       goto Cleanup;
     }
 
+    //
+    // We expect the Attributes, FilePathListLength, and L'\0'-terminated
+    // Description fields to be present.
+    //
+    if (BufferSize < sizeof *LoadOption + sizeof (CHAR16)) {
+      ShellPrintHiiEx (
+        -1,
+        -1,
+        NULL,
+        STRING_TOKEN (STR_BCFG_VAR_CORRUPT),
+        gShellBcfgHiiHandle,
+        L"bcfg",
+        VariableName
+        );
+      ++Errors;
+      goto Cleanup;
+    }
+
     if ((*(UINT16*)(Buffer+4)) != 0) {
       DevPath = AllocateZeroPool(*(UINT16*)(Buffer+4));
       if (DevPath != NULL) {

Modified: 
trunk/edk2/ShellPkg/Library/UefiShellBcfgCommandLib/UefiShellBcfgCommandLib.uni
===================================================================
--- 
trunk/edk2/ShellPkg/Library/UefiShellBcfgCommandLib/UefiShellBcfgCommandLib.uni 
    2016-01-21 18:40:05 UTC (rev 19709)
+++ 
trunk/edk2/ShellPkg/Library/UefiShellBcfgCommandLib/UefiShellBcfgCommandLib.uni 
    2016-01-21 18:40:09 UTC (rev 19710)
@@ -37,6 +37,7 @@
 #string STR_GEN_OUT_MEM           #language en-US "%H%s%N: Memory allocation 
was not successful.\r\n"
 #string STR_BCFG_WRITE_FAIL       #language en-US "%H%s%N: Unable to write to 
'%H%s%N'\r\n"
 #string STR_BCFG_READ_FAIL        #language en-US "%H%s%N: Unable to read from 
'%H%s%N'\r\n"
+#string STR_BCFG_VAR_CORRUPT      #language en-US "%H%s%N: Variable '%H%s%N' 
corrupt.\r\n"
 #string STR_BCFG_HANDLE           #language en-US "%H%s%N: The handle 
[%H%02x%N] does not have DevicePath.\r\n"
 #string STR_BCFG_FILE             #language en-US "%H%s%N: The file '%H%s%N' 
matches multiple files.\r\n"
 #string STR_BCFG_FILE_OPEN        #language en-US "%H%s%N: The file '%H%s%N' 
did not open.\r\n"


------------------------------------------------------------------------------
Site24x7 APM Insight: Get Deep Visibility into Application Performance
APM + Mobile APM + RUM: Monitor 3 App instances at just $35/Month
Monitor end-to-end web transactions and take corrective actions now
Troubleshoot faster and improve end-user experience. Signup Now!
http://pubads.g.doubleclick.net/gampad/clk?id=267308311&iu=/4140
_______________________________________________
edk2-commits mailing list
[email protected]
https://lists.sourceforge.net/lists/listinfo/edk2-commits

Reply via email to