Re: [edk2-devel] [PATCH] IntelFrameworkModulePkg/DebugLib: Fix string copy issue

["Wu, Hao A" <hao.a.wu@intel.com>]

> -----Original Message-----
> From: devel@edk2.groups.io [mailto:devel@edk2.groups.io] On Behalf Of
> Gao, Zhichao
> Sent: Tuesday, May 21, 2019 3:50 PM
> To: devel@edk2.groups.io
> Cc: Gao, Liming; Wu, Hao A
> Subject: [edk2-devel] [PATCH] IntelFrameworkModulePkg/DebugLib: Fix
> string copy issue
> 
> REF: https://bugzilla.tianocore.org/show_bug.cgi?id=1826
> 
> There is a bug to use AsciiStrCpyS to copy a truncated
> string. If would cause an assert because the truncated
> length is always less than the source string length. It
> should use the AsciiStrnCpyS instead.
> 
> Cc: Liming Gao <liming.gao@intel.com>
> Cc: Hao A Wu <hao.a.wu@intel.com>
> Signed-off-by: Zhichao Gao <zhichao.gao@intel.com>
> ---
>  .../Library/PeiDxeDebugLibReportStatusCode/DebugLib.c         | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git
> a/IntelFrameworkModulePkg/Library/PeiDxeDebugLibReportStatusCode/De
> bugLib.c
> b/IntelFrameworkModulePkg/Library/PeiDxeDebugLibReportStatusCode/De
> bugLib.c
> index e92601f89e..1840b6d683 100644
> ---
> a/IntelFrameworkModulePkg/Library/PeiDxeDebugLibReportStatusCode/De
> bugLib.c
> +++
> b/IntelFrameworkModulePkg/Library/PeiDxeDebugLibReportStatusCode/De
> bugLib.c
> @@ -150,7 +150,7 @@ DebugPrintMarker (
>    FormatString          = (CHAR8 *)((UINT64 *)(DebugInfo + 1) + 12);
> 
>    //
> -  // Copy the Format string into the record
> +  // Copy the Format string into the record. It will be truncated if it's too long.
>    //
>    // According to the content structure of Buffer shown above, the size of
>    // the FormatString buffer is the size of Buffer minus the Padding
> @@ -158,7 +158,7 @@ DebugPrintMarker (
>    // variable arguments (12 * sizeof (UINT64)).
>    //
>    DestBufferSize = sizeof (Buffer) - 4 - sizeof (EFI_DEBUG_INFO) - 12 * sizeof
> (UINT64);
> -  AsciiStrCpyS (FormatString, DestBufferSize / sizeof (CHAR8), Format);
> +  AsciiStrnCpyS (FormatString, DestBufferSize / sizeof (CHAR8), Format,
> DestBufferSize / sizeof (CHAR8) - 1);

Reviewed-by: Hao A Wu <hao.a.wu@intel.com>

Best Regards,
Hao Wu

> 
>    //
>    // The first 12 * sizeof (UINT64) bytes following EFI_DEBUG_INFO are for
> variable arguments
> --
> 2.21.0.windows.1
> 
> 
>