Re: [edk2-devel] [PATCH 1/1] MdeModulePkg/EbcDxe: Mitigate memcpy intrinsics

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

> -----Original Message-----
> From: devel@edk2.groups.io <devel@edk2.groups.io> On Behalf Of Marvin
> H?user
> Sent: Monday, August 16, 2021 4:12 AM
> To: devel@edk2.groups.io
> Cc: Wang, Jian J <jian.j.wang@intel.com>; Wu, Hao A <hao.a.wu@intel.com>;
> Vitaly Cheptsov <vit9696@protonmail.com>
> Subject: [edk2-devel] [PATCH 1/1] MdeModulePkg/EbcDxe: Mitigate
> memcpy intrinsics
> 
> Assignments of structure values cause the emission of memcpy()
> intrinsics by the CLANG38 toolchain. Substitute the assignments with
> calls to CopyMem() to mitigate the issue.


Reviewed-by: Hao A Wu <hao.a.wu@intel.com>
Will merge after the upcoming stable tag.

Best Regards,
Hao Wu


> 
> Cc: Jian J Wang <jian.j.wang@intel.com>
> Cc: Hao A Wu <hao.a.wu@intel.com>
> Cc: Vitaly Cheptsov <vit9696@protonmail.com>
> Signed-off-by: Marvin Häuser <mhaeuser@posteo.de>
> ---
>  MdeModulePkg/Universal/EbcDxe/EbcDebugger/Edb.c              | 6 +++++-
>  MdeModulePkg/Universal/EbcDxe/EbcDebugger/EdbCmdBreakpoint.c | 6
> +++++-
>  MdeModulePkg/Universal/EbcDxe/EbcDebugger/EdbHook.c          | 6 +++++-
>  3 files changed, 15 insertions(+), 3 deletions(-)
> 
> diff --git a/MdeModulePkg/Universal/EbcDxe/EbcDebugger/Edb.c
> b/MdeModulePkg/Universal/EbcDxe/EbcDebugger/Edb.c
> index 611b2de5d81f..e417f4870f3d 100644
> --- a/MdeModulePkg/Universal/EbcDxe/EbcDebugger/Edb.c
> +++ b/MdeModulePkg/Universal/EbcDxe/EbcDebugger/Edb.c
> @@ -219,7 +219,11 @@ EdbCheckBreakpoint (
>        //
> 
>        // If hit, record current breakpoint
> 
>        //
> 
> -      DebuggerPrivate-
> >DebuggerBreakpointContext[EFI_DEBUGGER_BREAKPOINT_MAX] =
> DebuggerPrivate->DebuggerBreakpointContext[Index];
> 
> +      CopyMem (
> 
> +        &DebuggerPrivate-
> >DebuggerBreakpointContext[EFI_DEBUGGER_BREAKPOINT_MAX],
> 
> +        &DebuggerPrivate->DebuggerBreakpointContext[Index],
> 
> +        sizeof (DebuggerPrivate-
> >DebuggerBreakpointContext[EFI_DEBUGGER_BREAKPOINT_MAX])
> 
> +        );
> 
>        DebuggerPrivate-
> >DebuggerBreakpointContext[EFI_DEBUGGER_BREAKPOINT_MAX].State =
> TRUE;
> 
>        //
> 
>        // Do not set Breakpoint flag. We record the address here just let it not
> patch breakpoint address when de-init.
> 
> diff --git
> a/MdeModulePkg/Universal/EbcDxe/EbcDebugger/EdbCmdBreakpoint.c
> b/MdeModulePkg/Universal/EbcDxe/EbcDebugger/EdbCmdBreakpoint.c
> index e0c797be247f..5d32c684066e 100644
> --- a/MdeModulePkg/Universal/EbcDxe/EbcDebugger/EdbCmdBreakpoint.c
> +++
> b/MdeModulePkg/Universal/EbcDxe/EbcDebugger/EdbCmdBreakpoint.c
> @@ -158,7 +158,11 @@ DebuggerBreakpointDel (
>    // Delete this breakpoint
> 
>    //
> 
>    for (BpIndex = Index; BpIndex < DebuggerPrivate-
> >DebuggerBreakpointCount - 1; BpIndex++) {
> 
> -    DebuggerPrivate->DebuggerBreakpointContext[BpIndex] =
> DebuggerPrivate->DebuggerBreakpointContext[BpIndex + 1];
> 
> +    CopyMem (
> 
> +      &DebuggerPrivate->DebuggerBreakpointContext[BpIndex],
> 
> +      &DebuggerPrivate->DebuggerBreakpointContext[BpIndex + 1],
> 
> +      sizeof (DebuggerPrivate->DebuggerBreakpointContext[BpIndex])
> 
> +      );
> 
>    }
> 
>    ZeroMem (
> 
>      &DebuggerPrivate->DebuggerBreakpointContext[BpIndex],
> 
> diff --git a/MdeModulePkg/Universal/EbcDxe/EbcDebugger/EdbHook.c
> b/MdeModulePkg/Universal/EbcDxe/EbcDebugger/EdbHook.c
> index 83257a2c25fe..1bfe5240c760 100644
> --- a/MdeModulePkg/Universal/EbcDxe/EbcDebugger/EdbHook.c
> +++ b/MdeModulePkg/Universal/EbcDxe/EbcDebugger/EdbHook.c
> @@ -230,7 +230,11 @@ EbcDebuggerPushTraceDestEntry (
>      //
> 
>      ASSERT
> (mDebuggerPrivate.TraceEntry[EFI_DEBUGGER_TRACE_MAX].Type == Type);
> 
>      for (Index = 0; Index < EFI_DEBUGGER_TRACE_MAX; Index++) {
> 
> -      mDebuggerPrivate.TraceEntry[Index] =
> mDebuggerPrivate.TraceEntry[Index + 1];
> 
> +      CopyMem (
> 
> +        &mDebuggerPrivate.TraceEntry[Index],
> 
> +        &mDebuggerPrivate.TraceEntry[Index + 1],
> 
> +        sizeof (mDebuggerPrivate.TraceEntry[Index])
> 
> +        );
> 
>      }
> 
>      mDebuggerPrivate.TraceEntry[EFI_DEBUGGER_CALLSTACK_MAX -
> 1].DestAddress = DestEntry;
> 
>      mDebuggerPrivate.TraceEntryCount = EFI_DEBUGGER_TRACE_MAX;
> 
> --
> 2.31.1
> 
> 
> 
> 
>