From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id DFD6226AC2; Tue, 16 Jan 2024 00:15:22 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="mJz+XqLG" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 60417C433A6; Tue, 16 Jan 2024 00:15:21 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1705364122; bh=dpJBmRkvN5a1m3Hw4ezVRUa5yHqdrRbbSVIB+kwRQAE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=mJz+XqLGkDQSU3+UlymI1xq7jsn5yY1elaA/hzVVLGQBUjLwhrOWHKAvJ8gUu07if I8piK/Za5riseiRHb2R19XVDI0vhVzKH6pY2Dr5gooMeC6P6dIdKhXIKZMzZ9+G3Rr SC22Y1+i81tWUCVhJtCT+SgehCrusXCMz78VV3te/JDAhziQZQ9iCB8pK1xbsveGXh OT9yl9Fs+ueQdyIWQ9jRof52X5Mxc1ml7sYRyiWIplUBWdeLauPIrw2PPpJYlv587X 0S2i0mkmYO7LF27jJwGN5waLJ6ahQvtHl5tIN477AwHrWC7G8A14ibfH9GMkNv0Kct zKZVvmALJEIlQ== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Dmitry Antipov , Kees Cook , "Rafael J . Wysocki" , Sasha Levin , rafael@kernel.org, linux-acpi@vger.kernel.org, linux-hardening@vger.kernel.org Subject: [PATCH AUTOSEL 5.4 5/7] PNP: ACPI: fix fortify warning Date: Mon, 15 Jan 2024 19:15:10 -0500 Message-ID: <20240116001514.214199-5-sashal@kernel.org> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20240116001514.214199-1-sashal@kernel.org> References: <20240116001514.214199-1-sashal@kernel.org> Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore X-stable-base: Linux 5.4.267 Content-Transfer-Encoding: 8bit From: Dmitry Antipov [ Upstream commit ba3f5058db437d919f8468db50483dd9028ff688 ] When compiling with gcc version 14.0.0 20231126 (experimental) and CONFIG_FORTIFY_SOURCE=y, I've noticed the following: In file included from ./include/linux/string.h:295, from ./include/linux/bitmap.h:12, from ./include/linux/cpumask.h:12, from ./arch/x86/include/asm/paravirt.h:17, from ./arch/x86/include/asm/cpuid.h:62, from ./arch/x86/include/asm/processor.h:19, from ./arch/x86/include/asm/cpufeature.h:5, from ./arch/x86/include/asm/thread_info.h:53, from ./include/linux/thread_info.h:60, from ./arch/x86/include/asm/preempt.h:9, from ./include/linux/preempt.h:79, from ./include/linux/spinlock.h:56, from ./include/linux/mmzone.h:8, from ./include/linux/gfp.h:7, from ./include/linux/slab.h:16, from ./include/linux/resource_ext.h:11, from ./include/linux/acpi.h:13, from drivers/pnp/pnpacpi/rsparser.c:11: In function 'fortify_memcpy_chk', inlined from 'pnpacpi_parse_allocated_vendor' at drivers/pnp/pnpacpi/rsparser.c:158:3, inlined from 'pnpacpi_allocated_resource' at drivers/pnp/pnpacpi/rsparser.c:249:3: ./include/linux/fortify-string.h:588:25: warning: call to '__read_overflow2_field' declared with attribute warning: detected read beyond size of field (2nd parameter); maybe use struct_group()? [-Wattribute-warning] 588 | __read_overflow2_field(q_size_field, size); | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ According to the comments in include/linux/fortify-string.h, 'memcpy()', 'memmove()' and 'memset()' must not be used beyond individual struct members to ensure that the compiler can enforce protection against buffer overflows, and, IIUC, this also applies to partial copies from the particular member ('vendor->byte_data' in this case). So it should be better (and safer) to do both copies at once (and 'byte_data' of 'struct acpi_resource_vendor_typed' seems to be a good candidate for '__counted_by(byte_length)' as well). Signed-off-by: Dmitry Antipov Reviewed-by: Kees Cook Signed-off-by: Rafael J. Wysocki Signed-off-by: Sasha Levin --- drivers/pnp/pnpacpi/rsparser.c | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-) diff --git a/drivers/pnp/pnpacpi/rsparser.c b/drivers/pnp/pnpacpi/rsparser.c index da78dc77aed3..9879deb4dc0b 100644 --- a/drivers/pnp/pnpacpi/rsparser.c +++ b/drivers/pnp/pnpacpi/rsparser.c @@ -151,13 +151,13 @@ static int vendor_resource_matches(struct pnp_dev *dev, static void pnpacpi_parse_allocated_vendor(struct pnp_dev *dev, struct acpi_resource_vendor_typed *vendor) { - if (vendor_resource_matches(dev, vendor, &hp_ccsr_uuid, 16)) { - u64 start, length; + struct { u64 start, length; } range; - memcpy(&start, vendor->byte_data, sizeof(start)); - memcpy(&length, vendor->byte_data + 8, sizeof(length)); - - pnp_add_mem_resource(dev, start, start + length - 1, 0); + if (vendor_resource_matches(dev, vendor, &hp_ccsr_uuid, + sizeof(range))) { + memcpy(&range, vendor->byte_data, sizeof(range)); + pnp_add_mem_resource(dev, range.start, range.start + + range.length - 1, 0); } } -- 2.43.0