From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: mx.groups.io; dkim=missing; spf=pass (domain: redhat.com, ip: 209.132.183.28, mailfrom: lersek@redhat.com) Received: from mx1.redhat.com (mx1.redhat.com [209.132.183.28]) by groups.io with SMTP; Thu, 05 Sep 2019 11:50:59 -0700 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.phx2.redhat.com [10.5.11.15]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 51A513175293; Thu, 5 Sep 2019 18:50:59 +0000 (UTC) Received: from lacos-laptop-7.usersys.redhat.com (ovpn-116-133.ams2.redhat.com [10.36.116.133]) by smtp.corp.redhat.com (Postfix) with ESMTP id 16C385D6A3; Thu, 5 Sep 2019 18:50:57 +0000 (UTC) Subject: Re: [edk2-devel] [patch 1/3] EmbeddedPkg: Unload image on EFI_SECURITY_VIOLATION To: devel@edk2.groups.io, dandan.bi@intel.com Cc: Leif Lindholm , Ard Biesheuvel References: <20190904082555.35424-1-dandan.bi@intel.com> <20190904082555.35424-2-dandan.bi@intel.com> From: "Laszlo Ersek" Message-ID: <84006098-6d8f-6529-544f-8b8c5fe2db8c@redhat.com> Date: Thu, 5 Sep 2019 20:50:57 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.9.1 MIME-Version: 1.0 In-Reply-To: <20190904082555.35424-2-dandan.bi@intel.com> X-Scanned-By: MIMEDefang 2.79 on 10.5.11.15 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.49]); Thu, 05 Sep 2019 18:50:59 +0000 (UTC) Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit On 09/04/19 10:25, Dandan Bi wrote: > For the LoadImage() boot service, with EFI_SECURITY_VIOLATION retval, > the Image was loaded and an ImageHandle was created with a valid > EFI_LOADED_IMAGE_PROTOCOL, but the image can not be started right now. > This follows UEFI Spec. > > But if the caller of LoadImage() doesn't have the option to defer > the execution of an image, we can not treat EFI_SECURITY_VIOLATION > like any other LoadImage() error, we should unload image for the > EFI_SECURITY_VIOLATION to avoid resource leak. > > This patch is to do error handling for EFI_SECURITY_VIOLATION explicitly > for the callers in EmbeddedPkg which don't have the policy to defer the > execution of the image. > > Cc: Leif Lindholm > Cc: Ard Biesheuvel > Cc: Laszlo Ersek > REF: https://bugzilla.tianocore.org/show_bug.cgi?id=1992 > Signed-off-by: Dandan Bi > --- > .../AndroidFastboot/Arm/BootAndroidBootImg.c | 9 +++++++++ > .../Library/AndroidBootImgLib/AndroidBootImgLib.c | 12 ++++++++++++ > 2 files changed, 21 insertions(+) > > diff --git a/EmbeddedPkg/Application/AndroidFastboot/Arm/BootAndroidBootImg.c b/EmbeddedPkg/Application/AndroidFastboot/Arm/BootAndroidBootImg.c > index 591afbe7cc..9fa28e3390 100644 > --- a/EmbeddedPkg/Application/AndroidFastboot/Arm/BootAndroidBootImg.c > +++ b/EmbeddedPkg/Application/AndroidFastboot/Arm/BootAndroidBootImg.c > @@ -71,10 +71,19 @@ StartEfiApplication ( > > // Load the image from the device path with Boot Services function > Status = gBS->LoadImage (TRUE, ParentImageHandle, DevicePath, NULL, 0, > &ImageHandle); > if (EFI_ERROR (Status)) { > + // > + // With EFI_SECURITY_VIOLATION retval, the Image was loaded and an ImageHandle was created > + // with a valid EFI_LOADED_IMAGE_PROTOCOL, but the image can not be started right now. > + // If the caller doesn't have the option to defer the execution of an image, we should > + // unload image for the EFI_SECURITY_VIOLATION to avoid resource leak. > + // > + if (Status == EFI_SECURITY_VIOLATION) { > + gBS->UnloadImage (ImageHandle); > + } > return Status; > } > > // Passed LoadOptions to the EFI Application > if (LoadOptionsSize != 0) { The return status exists here originally, so this change is strictly an improvement. But: > diff --git a/EmbeddedPkg/Library/AndroidBootImgLib/AndroidBootImgLib.c b/EmbeddedPkg/Library/AndroidBootImgLib/AndroidBootImgLib.c > index d9e7aa7d2b..2e9e74db1d 100644 > --- a/EmbeddedPkg/Library/AndroidBootImgLib/AndroidBootImgLib.c > +++ b/EmbeddedPkg/Library/AndroidBootImgLib/AndroidBootImgLib.c > @@ -439,10 +439,22 @@ AndroidBootImgBoot ( > + KernelSize; > > Status = gBS->LoadImage (TRUE, gImageHandle, > (EFI_DEVICE_PATH *)&KernelDevicePath, > (VOID*)(UINTN)Kernel, KernelSize, &ImageHandle); > + if (EFI_ERROR (Status)) { > + // > + // With EFI_SECURITY_VIOLATION retval, the Image was loaded and an ImageHandle was created > + // with a valid EFI_LOADED_IMAGE_PROTOCOL, but the image can not be started right now. > + // If the caller doesn't have the option to defer the execution of an image, we should > + // unload image for the EFI_SECURITY_VIOLATION to avoid resource leak. > + // > + if (Status == EFI_SECURITY_VIOLATION) { > + gBS->UnloadImage (ImageHandle); > + } > + return Status; > + } > > // Set kernel arguments > Status = gBS->HandleProtocol (ImageHandle, &gEfiLoadedImageProtocolGuid, > (VOID **) &ImageInfo); > ImageInfo->LoadOptions = NewKernelArg; > The return status is introduced afresh here. And, at this point in the function, we have allocated at least "NewKernelArg". (And probably more resources.) If we take an early return here, then we're going to leak NewKernelArg. Hm... Hmm. Well, even without this patch, if the loaded and started image returns, then the AndroidBootImgBoot() function leaks "NewKernelArg" anyway. Sigh. I guess the error handling in this function should be cleaned up first, to solve the present issue cleanly. On the other hand, I'm not sure how much this function is used at all. And I guess the patch doesn't make things worse than they are. Acked-by: Laszlo Ersek