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dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:MIME-Version:Cc:List-Subscribe: List-Help:List-Post:List-Archive:List-Unsubscribe:List-Id:References: In-Reply-To:Message-Id:Date:Subject:To:From:Reply-To:Content-ID: Content-Description:Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc :Resent-Message-ID:List-Owner; bh=WcGaEl87K042/MtrdICWqUpP1FLYrfym7DVuAA7QYHA=; b=i2AGMpBJEYBFvHPWylhdc+wFSR WbylygaxVSvWNRb/YhZ7RYYqzwfH0Na3t37SjgYWtfecJ8IOX25ZUme4ig/FtMhLsYWP+WKjQbOPj /WFb/KB2pSSZhvjWGQLFJWHmp3JEJdTDxXl+k2Mne8SH/g1pIa13J9l39jDZ5gQWfkdAHWsge010l IHDY8ksc9qBWvD6bL/HC0UgjGWRdKG9y/YCmVHJDvHEzVep8EoTBeZM9tamPf4BP8ltEkzGkqXYP5 8vd8uiWfSWlvbiuh+lvAq6xBowpCrBgdaj4FUqXt6bxWSL/KCMq6r35gTVpQWKX91b/Qa4IVB6yLI 08YsndGw==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1jISxQ-0002UE-0I; Sun, 29 Mar 2020 08:06:12 +0000 Received: from mail.kernel.org ([198.145.29.99]) by bombadil.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1jISxF-0002O4-7d for linux-arm-kernel@lists.infradead.org; Sun, 29 Mar 2020 08:06:02 +0000 Received: from e123331-lin.home (amontpellier-657-1-18-247.w109-210.abo.wanadoo.fr [109.210.65.247]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 96A2120732; Sun, 29 Mar 2020 08:05:59 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1585469161; bh=GbZAaOXgR3jz+8nkwefkR612DbLVdMAnKZhYHRnkl8s=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=zk/uI30qXFimglH5Ti+VIiM5pUoCKU5NADoPlxz396SSOsDLncaK3L1SSgO/yGKMN G38KT4Fr3VvufkJb8o5kNls+WlZSHVkPn5kPqrUOIpQrM/iUaiiC7VXMIzGkN1GMvJ YVZaBGhQgRdISXjwx2V6SlgFyJcp9mna5T1F0Wj4= From: Ard Biesheuvel To: linux-efi@vger.kernel.org, Ingo Molnar , Thomas Gleixner Subject: [PATCH 1/2] efi/libstub/arm64: avoid image_base value from efi_loaded_image Date: Sun, 29 Mar 2020 10:05:43 +0200 Message-Id: <20200329080544.25715-2-ardb@kernel.org> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20200329080544.25715-1-ardb@kernel.org> References: <20200329080544.25715-1-ardb@kernel.org> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20200329_010601_291462_0AA73D2D X-CRM114-Status: GOOD ( 12.62 ) X-Spam-Score: -5.4 (-----) X-Spam-Report: SpamAssassin version 3.4.4 on bombadil.infradead.org summary: Content analysis details: (-5.4 points) pts rule name description ---- ---------------------- -------------------------------------------------- -5.0 RCVD_IN_DNSWL_HI RBL: Sender listed at https://www.dnswl.org/, high trust [198.145.29.99 listed in list.dnswl.org] 0.0 SPF_HELO_NONE SPF: HELO does not publish an SPF Record -0.0 SPF_PASS SPF: sender matches SPF record -0.1 DKIM_VALID Message has at least one valid DKIM or DK signature -0.1 DKIM_VALID_EF Message has a valid DKIM or DK signature from envelope-from domain 0.1 DKIM_SIGNED Message has a DKIM or DK signature, not necessarily valid -0.1 DKIM_VALID_AU Message has a valid DKIM or DK signature from author's domain -0.2 DKIMWL_WL_HIGH DKIMwl.org - Whitelisted High sender X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Ard Biesheuvel , linux-arm-kernel@lists.infradead.org MIME-Version: 1.0 Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org Commit 9f9223778ef3 ("efi/libstub/arm: Make efi_entry() an ordinary PE/COFF entrypoint") did some code refactoring to get rid of the EFI entry point assembler code, and in the process, it got rid of the assignment of image_addr to the value of _text. Instead, it switched to using the image_base field of the efi_loaded_image struct provided by UEFI, which should contain the same value. However, Michael reports that this is not the case: older GRUB builds corrupt this value in some way, and since we can easily switch back to referring to _text to discover this value, let's simply do that. While at it, fix another issue in commit 9f9223778ef3, which may result in the unassigned image_addr to be misidentified as the preferred load offset of the kernel, which is unlikely but will cause a boot crash if it does occur. Finally, let's add a warning if the _text vs. image_base discrepancy is detected, so we can tell more easily how widespread this issue actually is. Reported-by: Michael Kelley Tested-by: Michael Kelley Signed-off-by: Ard Biesheuvel --- drivers/firmware/efi/libstub/arm64-stub.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/drivers/firmware/efi/libstub/arm64-stub.c b/drivers/firmware/efi/libstub/arm64-stub.c index 9254cd8ab2d3..db0c1a9c1699 100644 --- a/drivers/firmware/efi/libstub/arm64-stub.c +++ b/drivers/firmware/efi/libstub/arm64-stub.c @@ -116,6 +116,7 @@ efi_status_t handle_kernel_image(unsigned long *image_addr, * Mustang), we can still place the kernel at the address * 'dram_base + TEXT_OFFSET'. */ + *image_addr = (unsigned long)_text; if (*image_addr == preferred_offset) return EFI_SUCCESS; @@ -140,7 +141,11 @@ efi_status_t handle_kernel_image(unsigned long *image_addr, } *image_addr = *reserve_addr + TEXT_OFFSET; } - memcpy((void *)*image_addr, image->image_base, kernel_size); + + if (image->image_base != _text) + pr_efi_err("FIRMWARE BUG: efi_loaded_image_t::image_base has bogus value\n"); + + memcpy((void *)*image_addr, _text, kernel_size); return EFI_SUCCESS; }