From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received-SPF: Pass (sender SPF authorized) identity=mailfrom; client-ip=66.187.233.73; helo=mx1.redhat.com; envelope-from=lersek@redhat.com; receiver=edk2-devel@lists.01.org Received: from mx1.redhat.com (mx3-rdu2.redhat.com [66.187.233.73]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ml01.01.org (Postfix) with ESMTPS id 9FC04210D97AE for ; Tue, 7 Aug 2018 04:50:28 -0700 (PDT) Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.rdu2.redhat.com [10.11.54.5]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id E9B0A40216E4; Tue, 7 Aug 2018 11:50:26 +0000 (UTC) Received: from lacos-laptop-7.usersys.redhat.com (ovpn-120-247.rdu2.redhat.com [10.10.120.247]) by smtp.corp.redhat.com (Postfix) with ESMTP id 16BCA1C59C; Tue, 7 Aug 2018 11:50:25 +0000 (UTC) To: Ruiyu Ni , edk2-devel@lists.01.org Cc: Star Zeng , "Wang, Jian J" References: <20180807055830.321912-1-ruiyu.ni@intel.com> From: Laszlo Ersek Message-ID: <8d034dc3-8a3e-237e-594c-2cc3f419bb4b@redhat.com> Date: Tue, 7 Aug 2018 13:50:25 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.7.0 MIME-Version: 1.0 In-Reply-To: <20180807055830.321912-1-ruiyu.ni@intel.com> X-Scanned-By: MIMEDefang 2.79 on 10.11.54.5 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.11.55.5]); Tue, 07 Aug 2018 11:50:26 +0000 (UTC) X-Greylist: inspected by milter-greylist-4.5.16 (mx1.redhat.com [10.11.55.5]); Tue, 07 Aug 2018 11:50:26 +0000 (UTC) for IP:'10.11.54.5' DOMAIN:'int-mx05.intmail.prod.int.rdu2.redhat.com' HELO:'smtp.corp.redhat.com' FROM:'lersek@redhat.com' RCPT:'' Subject: Re: [PATCH v2] IntelFrameworkModulePkg/Csm: Set CSM memory executable X-BeenThere: edk2-devel@lists.01.org X-Mailman-Version: 2.1.27 Precedence: list List-Id: EDK II Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 07 Aug 2018 11:50:28 -0000 Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Hi Ray, On 08/07/18 07:58, Ruiyu Ni wrote: > Commit b22a62be5cdc8fd19d87ec1ecfa5b28fb9be50ad > * IntelFrameworkModule/LegacyBios:Use reserved memory for legacy data > allocates reserved memory for holding legacy code/data. > > But with PcdDxeNxMemoryProtectionPolicy set to certain value to > forbid execution when code is in certain type of memory, it's > possible that a platform forbids execution when code is in reserved > memory. The patch calls GCD service to allow such case otherwise > CPU exception may occur. > > Code execution in BSCode area should be enabled by platform by > default. > > Contributed-under: TianoCore Contribution Agreement 1.1 > Signed-off-by: Ruiyu Ni > Cc: Star Zeng > Cc: Laszlo Ersek > --- > .../Csm/LegacyBiosDxe/LegacyBios.c | 22 +++++++++++++++++----- > 1 file changed, 17 insertions(+), 5 deletions(-) > > diff --git a/IntelFrameworkModulePkg/Csm/LegacyBiosDxe/LegacyBios.c b/IntelFrameworkModulePkg/Csm/LegacyBiosDxe/LegacyBios.c > index 8f14687b28..f86d00b53f 100644 > --- a/IntelFrameworkModulePkg/Csm/LegacyBiosDxe/LegacyBios.c > +++ b/IntelFrameworkModulePkg/Csm/LegacyBiosDxe/LegacyBios.c > @@ -64,8 +64,9 @@ AllocateLegacyMemory ( > OUT EFI_PHYSICAL_ADDRESS *Result > ) > { > - EFI_STATUS Status; > - EFI_PHYSICAL_ADDRESS MemPage; > + EFI_STATUS Status; > + EFI_PHYSICAL_ADDRESS MemPage; > + EFI_GCD_MEMORY_SPACE_DESCRIPTOR MemDesc; > > // > // Allocate Pages of memory less <= StartPageAddress > @@ -83,10 +84,21 @@ AllocateLegacyMemory ( > // > if (!EFI_ERROR (Status)) { > *Result = (EFI_PHYSICAL_ADDRESS) (UINTN) MemPage; > + if (MemoryType != EfiBootServicesCode) { > + // > + // Make sure that the buffer can be used to store code. > + // > + Status = gDS->GetMemorySpaceDescriptor (MemPage, &MemDesc); > + if (!EFI_ERROR (Status) && (MemDesc.Attributes & EFI_MEMORY_XP) != 0) { > + Status = gDS->SetMemorySpaceAttributes ( > + MemPage, > + EFI_PAGES_TO_SIZE (Pages), > + MemDesc.Attributes & (~EFI_MEMORY_XP) > + ); > + } > + } > } > - // > - // If reach here the status = EFI_SUCCESS > - // > + > return Status; > } > > thanks for the update. I think the commit message is now *great*. I'm adding Jian (like Star did for v1) so he can comment on the general idea. I have another remark regarding the logic -- and I apologize for missing it in v1 --: if the SetMemorySpaceAttributes() calls fails, we correctly propagate the status to the caller; however, we leak the allocated memory. If SetMemorySpaceAttributes() fails, we should release the memory before we return the error. Can you please CC Jian on v3 at once? Thank you! Laszlo