Re: [PATCH] EmbeddedPkg/NonCoherentDmaLib: avoid dereferencing bogus buffer address

["Ard Biesheuvel" <ard.biesheuvel@arm.com>]

On 6/17/20 6:14 PM, Leif Lindholm wrote:
> On Wed, Jun 17, 2020 at 17:38:24 +0200, Ard Biesheuvel wrote:
>> The bounce buffering code in NonCoherentDmaLib copies data into the
>> bounce buffer using CopyMem(), but passes Map->HostAddress as the
>> source of the copy before it has been assigned its correct value.
> 
> Whoops.
> 
>> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@arm.com>
> 
> Reviewed-by: Leif Lindholm <leif@nuviainc.com>
> 

Thanks

Merged as 8f22a331b955bd3f8077c7fa83bafeec566d6718


>> ---
>>   EmbeddedPkg/Library/NonCoherentDmaLib/NonCoherentDmaLib.c | 3 +--
>>   1 file changed, 1 insertion(+), 2 deletions(-)
>>
>> diff --git a/EmbeddedPkg/Library/NonCoherentDmaLib/NonCoherentDmaLib.c b/EmbeddedPkg/Library/NonCoherentDmaLib/NonCoherentDmaLib.c
>> index 115345765435..9c8ef5bfb533 100644
>> --- a/EmbeddedPkg/Library/NonCoherentDmaLib/NonCoherentDmaLib.c
>> +++ b/EmbeddedPkg/Library/NonCoherentDmaLib/NonCoherentDmaLib.c
>> @@ -225,8 +225,7 @@ DmaMap (
>>       }
>>   
>>       if (Map->Operation == MapOperationBusMasterRead) {
>> -      CopyMem (Map->BufferAddress, (VOID *)(UINTN)Map->HostAddress,
>> -        *NumberOfBytes);
>> +      CopyMem (Map->BufferAddress, (VOID *)(UINTN)HostAddress, *NumberOfBytes);
>>       }
>>       mCpu->FlushDataCache (mCpu, (UINTN)Map->BufferAddress, AllocSize,
>>               EfiCpuFlushTypeWriteBack);
>> -- 
>> 2.27.0
>>