From: "Chiu, Chasel" <chasel.chiu@intel.com>
To: "devel@edk2.groups.io" <devel@edk2.groups.io>,
"Zhang, Shenglei" <shenglei.zhang@intel.com>
Cc: "Kubacki, Michael A" <michael.a.kubacki@intel.com>,
"Desimone, Nathaniel L" <nathaniel.l.desimone@intel.com>,
"Gao, Liming" <liming.gao@intel.com>
Subject: Re: [edk2-devel] [PATCH] MinPlatformPkg/SecFspWrapperPlatformSecLib: Change TopOfTemporaryRam type
Date: Wed, 4 Sep 2019 12:13:27 +0000 [thread overview]
Message-ID: <3C3EFB470A303B4AB093197B6777CCEC5048145B@PGSMSX111.gar.corp.intel.com> (raw)
In-Reply-To: <20190902123452.27716-1-shenglei.zhang@intel.com>
Hi Shenglei,
Would you please elaborate a little on how casting to UINTN can resolve the overflow scenario and why 64bits OS will affect this code?
Thanks!
Chasel
> -----Original Message-----
> From: devel@edk2.groups.io <devel@edk2.groups.io> On Behalf Of Zhang,
> Shenglei
> Sent: Monday, September 2, 2019 8:35 PM
> To: devel@edk2.groups.io
> Cc: Kubacki, Michael A <michael.a.kubacki@intel.com>; Chiu, Chasel
> <chasel.chiu@intel.com>; Desimone, Nathaniel L
> <nathaniel.l.desimone@intel.com>; Gao, Liming <liming.gao@intel.com>
> Subject: [edk2-devel] [PATCH] MinPlatformPkg/SecFspWrapperPlatformSecLib:
> Change TopOfTemporaryRam type
>
> Cast TopOfTemporaryRam's from UINT32 to UINTN in the expression.
> The original code (TopOfTemporaryRam - sizeof (UINT32)) may cause
> overflow. As a result the operation under 64-bit OS environment, (UINT)(...),
> may cast a overflowed 4-byte result to 8-byte one.
>
> Cc: Michael Kubacki <michael.a.kubacki@intel.com>
> Cc: Chasel Chiu <chasel.chiu@intel.com>
> Cc: Nate DeSimone <nathaniel.l.desimone@intel.com>
> Cc: Liming Gao <liming.gao@intel.com>
> Signed-off-by: Shenglei Zhang <shenglei.zhang@intel.com>
> ---
> .../Library/SecFspWrapperPlatformSecLib/SecGetPerformance.c | 2 +-
> .../SecFspWrapperPlatformSecLib/SecPlatformInformation.c | 2 +-
> 2 files changed, 2 insertions(+), 2 deletions(-)
>
> diff --git
> a/Platform/Intel/MinPlatformPkg/FspWrapper/Library/SecFspWrapperPlatfor
> mSecLib/SecGetPerformance.c
> b/Platform/Intel/MinPlatformPkg/FspWrapper/Library/SecFspWrapperPlatfor
> mSecLib/SecGetPerformance.c
> index c4eeb2b1..0cc42f96 100644
> ---
> a/Platform/Intel/MinPlatformPkg/FspWrapper/Library/SecFspWrapperPlatfor
> mSecLib/SecGetPerformance.c
> +++
> b/Platform/Intel/MinPlatformPkg/FspWrapper/Library/SecFspWrapperPlat
> +++ formSecLib/SecGetPerformance.c
> @@ -79,7 +79,7 @@ SecGetPerformance (
> //
> TopOfTemporaryRam = (UINT32)(UINTN)TopOfTemporaryRamPpi -
> sizeof(UINT32);
> TopOfTemporaryRam -= sizeof(UINT32) * 2;
> - Count = *(UINT32 *) (UINTN) (TopOfTemporaryRam - sizeof
> (UINT32));
> + Count = *(UINT32 *)((UINTN)TopOfTemporaryRam - sizeof
> (UINT32));
> Size = Count * sizeof (UINT32);
>
> Ticker = *(UINT64 *) (UINTN) (TopOfTemporaryRam - sizeof (UINT32) - Size
> - sizeof (UINT32) * 2); diff --git
> a/Platform/Intel/MinPlatformPkg/FspWrapper/Library/SecFspWrapperPlatfor
> mSecLib/SecPlatformInformation.c
> b/Platform/Intel/MinPlatformPkg/FspWrapper/Library/SecFspWrapperPlatfor
> mSecLib/SecPlatformInformation.c
> index 5b94ed2b..1bcee5f4 100644
> ---
> a/Platform/Intel/MinPlatformPkg/FspWrapper/Library/SecFspWrapperPlatfor
> mSecLib/SecPlatformInformation.c
> +++
> b/Platform/Intel/MinPlatformPkg/FspWrapper/Library/SecFspWrapperPlat
> +++ formSecLib/SecPlatformInformation.c
> @@ -61,7 +61,7 @@ SecPlatformInformation (
> //
> TopOfTemporaryRam = (UINT32)(UINTN)TopOfTemporaryRamPpi - sizeof
> (UINT32);
> TopOfTemporaryRam -= sizeof(UINT32) * 2;
> - Count = *((UINT32 *)(UINTN) (TopOfTemporaryRam - sizeof
> (UINT32)));
> + Count = *((UINT32 *)((UINTN)TopOfTemporaryRam - sizeof
> (UINT32)));
> Size = Count * sizeof (IA32_HANDOFF_STATUS);
>
> if ((*StructureSize) < (UINT64) Size) {
> --
> 2.18.0.windows.1
>
>
>
next prev parent reply other threads:[~2019-09-04 12:13 UTC|newest]
Thread overview: 12+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-09-02 12:34 [PATCH] MinPlatformPkg/SecFspWrapperPlatformSecLib: Change TopOfTemporaryRam type Zhang, Shenglei
2019-09-02 12:34 ` [PATCH] MinPlatformPkg/TestPointCheckLib: Add return value when OutTable is NULL Zhang, Shenglei
2019-09-02 14:04 ` Chiu, Chasel
2019-09-02 12:34 ` [PATCH] MinPlatformPkg/TestPointCheckLib: Add check for pointers Zhang, Shenglei
2019-09-02 14:01 ` Chiu, Chasel
2019-09-10 22:28 ` Nate DeSimone
2019-09-02 12:34 ` [PATCH] MinPlatformPkg/TestPointCheckLib: Add check for pointer Variable Zhang, Shenglei
2019-09-02 14:06 ` Chiu, Chasel
2019-09-04 12:13 ` Chiu, Chasel [this message]
2019-09-05 2:11 ` [edk2-devel] [PATCH] MinPlatformPkg/SecFspWrapperPlatformSecLib: Change TopOfTemporaryRam type Zhang, Shenglei
2019-09-05 2:53 ` Chiu, Chasel
2019-09-05 5:51 ` Zhang, Shenglei
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-list from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=3C3EFB470A303B4AB093197B6777CCEC5048145B@PGSMSX111.gar.corp.intel.com \
--to=devel@edk2.groups.io \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox