Re: [PATCH 3/4] Fix CodeQL warnings

[Paul Durrant <xadimgnik@xxxxxxxxx>]

On 12/08/2021 13:41, Owen Smith wrote:
> - ExAllocatePoolWithTag is deprecated in Win10 2004, use
>      ExAllocatePoolUninitialized instead
>
> Signed-off-by: Owen Smith <owen.smith@xxxxxxxxxx>
> ---
>   src/common/util.h    |  4 ++++
>   src/xenvbd/adapter.c | 12 ++++--------
>   src/xenvbd/base64.c  | 15 ++++-----------
>   3 files changed, 12 insertions(+), 19 deletions(-)
>
> diff --git a/src/common/util.h b/src/common/util.h
> index eddad4a..36a36dd 100644
> --- a/src/common/util.h
> +++ b/src/common/util.h
> @@ -151,8 +151,12 @@ __AllocatePoolWithTag(
>       __analysis_assume(PoolType == NonPagedPool ||
>                         PoolType == PagedPool);
>   
> +#if (_MSC_VER >= 1928) // VS 16.9 (EWDK 20344 or later)
> +    Buffer = ExAllocatePoolUninitialized(PoolType, NumberOfBytes, Tag);
> +#else
>   #pragma warning(suppress:28160) // annotation error
>       Buffer = ExAllocatePoolWithTag(PoolType, NumberOfBytes, Tag);
> +#endif
>       if (Buffer == NULL)
>           return NULL;
>   
> diff --git a/src/xenvbd/adapter.c b/src/xenvbd/adapter.c
> index 9fd2abc..5b17a6b 100644
> --- a/src/xenvbd/adapter.c
> +++ b/src/xenvbd/adapter.c
> @@ -102,13 +102,9 @@ __AdapterAllocate(
>       IN  ULONG   Size
>       )
>   {
> -    PVOID       Buffer;
> -    Buffer = ExAllocatePoolWithTag(NonPagedPool,
> -                                   Size,
> -                                   ADAPTER_POOL_TAG);
> -    if (Buffer)
> -        RtlZeroMemory(Buffer, Size);
We'll still need to zero the memory to maintain the semantics, right?

I'll amend the patch accordingly.

  Paul

> -    return Buffer;
> +    return __AllocatePoolWithTag(NonPagedPool,
> +                                 Size,
> +                                 ADAPTER_POOL_TAG);
>   }
>   
>   static FORCEINLINE VOID
> @@ -116,7 +112,7 @@ __AdapterFree(
>       IN  PVOID   Buffer
>       )
>   {
> -    ExFreePoolWithTag(Buffer, ADAPTER_POOL_TAG);
> +    __FreePoolWithTag(Buffer, ADAPTER_POOL_TAG);
>   }
>   
>   static FORCEINLINE PANSI_STRING
> diff --git a/src/xenvbd/base64.c b/src/xenvbd/base64.c
> index 0e62784..223579a 100644
> --- a/src/xenvbd/base64.c
> +++ b/src/xenvbd/base64.c
> @@ -44,15 +44,9 @@ Base64Allocate(
>       IN  ULONG   Size
>       )
>   {
> -    PVOID       Buffer;
> -
> -    Buffer = ExAllocatePoolWithTag(NonPagedPool,
> -                                   Size,
> -                                   BASE64_POOL_TAG);
> -    if (Buffer)
> -        RtlZeroMemory(Buffer, Size);
> -
> -    return Buffer;
> +    return __AllocatePoolWithTag(NonPagedPool,
> +                                 Size,
> +                                 BASE64_POOL_TAG);
>   }
>   
>   VOID
> @@ -60,8 +54,7 @@ Base64Free(
>       IN  PVOID   Buffer
>       )
>   {
> -    if (Buffer)
> -        ExFreePoolWithTag(Buffer, BASE64_POOL_TAG);
> +    __FreePoolWithTag(Buffer, BASE64_POOL_TAG);
>   }
>   
>   static FORCEINLINE UCHAR