[PATCH] MdeModulePkg/DxeCorePerformanceLib: Switch to UnicodeStrnToAsciiStrS

[PATCH] MdeModulePkg/DxeCorePerformanceLib: Switch to UnicodeStrnToAsciiStrS

[Jeff Brasen]

UnicodeStrToAsciiStrS requires that the source string is shorter than
the destination buffer and will ASSERT if this is not true. Switch to
UnicodeStrnToAsciiStrS as there are cases where the source string is
longer than the buffer allocated for the device path.

Signed-off-by: Jeff Brasen <jbrasen@nvidia.com>
---
 .../Library/DxeCorePerformanceLib/DxeCorePerformanceLib.c       | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/MdeModulePkg/Library/DxeCorePerformanceLib/DxeCorePerformanceLib.c b/MdeModulePkg/Library/DxeCorePerformanceLib/DxeCorePerformanceLib.c
index f500e20b32..89ae6fb964 100644
--- a/MdeModulePkg/Library/DxeCorePerformanceLib/DxeCorePerformanceLib.c
+++ b/MdeModulePkg/Library/DxeCorePerformanceLib/DxeCorePerformanceLib.c
@@ -879,7 +879,7 @@ GetDeviceInfoFromHandleAndUpdateLength (
         AsciiStringPtr = ComponentNameString;
       }
 
-      UnicodeStrToAsciiStrS(StringPtr, AsciiStringPtr, DevicePathStringSize);
+      UnicodeStrnToAsciiStrS(StringPtr, DevicePathStringSize - 1, AsciiStringPtr, DevicePathStringSize, &DevicePathStringSize);
       *Length += (UINT8)DevicePathStringSize;
       return EFI_SUCCESS;
     }
-- 
2.17.1

Re: [edk2-devel] [PATCH] MdeModulePkg/DxeCorePerformanceLib: Switch to UnicodeStrnToAsciiStrS

[Dandan Bi]

Thanks for the fix.
Could you also help update the UnicodeStrToAsciiStrS usage at line 840? Which potentially has the similar issue.
UnicodeStrToAsciiStrS(StringPtr, ComponentNameString, ControllerNameStringSize);


Thanks,
Dandan
> -----Original Message-----
> From: devel@edk2.groups.io <devel@edk2.groups.io> On Behalf Of Jeff
> Brasen
> Sent: Tuesday, June 2, 2020 5:13 AM
> To: devel@edk2.groups.io
> Cc: Bi, Dandan <dandan.bi@intel.com>; Gao, Liming <liming.gao@intel.com>;
> Jeff Brasen <jbrasen@nvidia.com>
> Subject: [edk2-devel] [PATCH] MdeModulePkg/DxeCorePerformanceLib:
> Switch to UnicodeStrnToAsciiStrS
> 
> UnicodeStrToAsciiStrS requires that the source string is shorter than the
> destination buffer and will ASSERT if this is not true. Switch to
> UnicodeStrnToAsciiStrS as there are cases where the source string is longer
> than the buffer allocated for the device path.
> 
> Signed-off-by: Jeff Brasen <jbrasen@nvidia.com>
> ---
>  .../Library/DxeCorePerformanceLib/DxeCorePerformanceLib.c       | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git
> a/MdeModulePkg/Library/DxeCorePerformanceLib/DxeCorePerformanceLi
> b.c
> b/MdeModulePkg/Library/DxeCorePerformanceLib/DxeCorePerformanceLi
> b.c
> index f500e20b32..89ae6fb964 100644
> ---
> a/MdeModulePkg/Library/DxeCorePerformanceLib/DxeCorePerformanceLi
> b.c
> +++
> b/MdeModulePkg/Library/DxeCorePerformanceLib/DxeCorePerformanceLi
> b.c
> @@ -879,7 +879,7 @@ GetDeviceInfoFromHandleAndUpdateLength (
>          AsciiStringPtr = ComponentNameString;
>        }
> 
> -      UnicodeStrToAsciiStrS(StringPtr, AsciiStringPtr, DevicePathStringSize);
> +      UnicodeStrnToAsciiStrS(StringPtr, DevicePathStringSize - 1,
> + AsciiStringPtr, DevicePathStringSize, &DevicePathStringSize);
>        *Length += (UINT8)DevicePathStringSize;
>        return EFI_SUCCESS;
>      }
> --
> 2.17.1
> 
> 
>