Re: [Patch] MdeModulePkg/PiSmmCore: Check valid memory range.

["Dong, Eric" <eric.dong@intel.com>]

Hi Star,

Good catch. I tried to boot an test platform and it passed. I assume it has cases to free the smm memory. Seems like actually it doesn't.

I will add test code to verify the patch and send v2 change.

Thanks,
Eric
> -----Original Message-----
> From: Zeng, Star
> Sent: Tuesday, August 21, 2018 5:35 PM
> To: Dong, Eric <eric.dong@intel.com>; edk2-devel@lists.01.org
> Cc: Zeng, Star <star.zeng@intel.com>
> Subject: RE: [Patch] MdeModulePkg/PiSmmCore: Check valid memory range.
> 
> Hi Eric,
> 
> About
> +  EFI_PHYSICAL_ADDRESS     Last;
> +  Last = Memory + EFI_PAGES_TO_SIZE (NumberOfPages);
> 
> Shouldn't "-1" be also added like the code below in
> ConvertSmmMemoryMapEntry()?
>   EFI_PHYSICAL_ADDRESS     End;
>   End = Memory + EFI_PAGES_TO_SIZE(NumberOfPages) - 1;
> 
> Could you double check the normal functionality (SMM AllocatePages +
> FreePages) with the patch?
> 
> 
> Thanks,
> Star
> -----Original Message-----
> From: Dong, Eric
> Sent: Tuesday, August 21, 2018 2:46 PM
> To: edk2-devel@lists.01.org
> Cc: Zeng, Star <star.zeng@intel.com>
> Subject: [Patch] MdeModulePkg/PiSmmCore: Check valid memory range.
> 
> Call BS.AllocatePages in DXE driver and call SMM FreePages with the address
> of the buffer allocated in the DXE driver. SMM FreePages success and add a
> non-SMRAM range into SMM heap list. This is not an expected behavior.
> SMM FreePages should return error for this case and not free the pages.
> 
> BZ: https://bugzilla.tianocore.org/show_bug.cgi?id=1098
> 
> Cc: Star Zeng <star.zeng@intel.com>
> Contributed-under: TianoCore Contribution Agreement 1.1
> Signed-off-by: Eric Dong <eric.dong@intel.com>
> ---
>  MdeModulePkg/Core/PiSmmCore/Page.c | 39
> ++++++++++++++++++++++++++++++++++++++
>  1 file changed, 39 insertions(+)
> 
> diff --git a/MdeModulePkg/Core/PiSmmCore/Page.c
> b/MdeModulePkg/Core/PiSmmCore/Page.c
> index 3699af7424..630678ccc3 100644
> --- a/MdeModulePkg/Core/PiSmmCore/Page.c
> +++ b/MdeModulePkg/Core/PiSmmCore/Page.c
> @@ -983,6 +983,41 @@ SmmInternalFreePages (
>    return SmmInternalFreePagesEx (Memory, NumberOfPages, FALSE);  }
> 
> +/**
> +  Check whether the input range is in smram.
> +
> +  @param  Memory                 Base address of memory being inputed.
> +  @param  NumberOfPages          The number of pages.
> +
> +  @retval TRUE   In the smram.
> +  @retval FALSE  Not in the smram.
> +
> +**/
> +BOOLEAN
> +InSmmRange (
> +  IN EFI_PHYSICAL_ADDRESS  Memory,
> +  IN UINTN                 NumberOfPages
> +  )
> +{
> +  LIST_ENTRY               *Link;
> +  MEMORY_MAP               *Entry;
> +  EFI_PHYSICAL_ADDRESS     Last;
> +
> +  Last = Memory + EFI_PAGES_TO_SIZE (NumberOfPages);
> +
> +  Link = gMemoryMap.ForwardLink;
> +  while (Link != &gMemoryMap) {
> +    Entry = CR (Link, MEMORY_MAP, Link, MEMORY_MAP_SIGNATURE);
> +    Link  = Link->ForwardLink;
> +
> +    if ((Entry->Start <= Memory) && (Entry->End >= Last)) {
> +      return TRUE;
> +    }
> +  }
> +
> +  return FALSE;
> +}
> +
>  /**
>    Frees previous allocated pages.
> 
> @@ -1004,6 +1039,10 @@ SmmFreePages (
>    EFI_STATUS  Status;
>    BOOLEAN     IsGuarded;
> 
> +  if (!InSmmRange(Memory, NumberOfPages)) {
> +    return EFI_NOT_FOUND;
> +  }
> +
>    IsGuarded = IsHeapGuardEnabled () && IsMemoryGuarded (Memory);
>    Status = SmmInternalFreePages (Memory, NumberOfPages, IsGuarded);
>    if (!EFI_ERROR (Status)) {
> --
> 2.15.0.windows.1