From patchwork Mon Nov 27 14:58:50 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Dmitry Antipov X-Patchwork-Id: 13469765 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=yandex.ru header.i=@yandex.ru header.b="wb5OPor9" X-Greylist: delayed 320 seconds by postgrey-1.37 at lindbergh.monkeyblade.net; Mon, 27 Nov 2023 07:05:23 PST Received: from forward200a.mail.yandex.net (forward200a.mail.yandex.net [IPv6:2a02:6b8:c0e:500:1:45:d181:d200]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 85FF6BB for ; Mon, 27 Nov 2023 07:05:23 -0800 (PST) Received: from forward102a.mail.yandex.net (forward102a.mail.yandex.net [IPv6:2a02:6b8:c0e:500:1:45:d181:d102]) by forward200a.mail.yandex.net (Yandex) with ESMTP id C9C4667DF5 for ; Mon, 27 Nov 2023 18:00:05 +0300 (MSK) Received: from mail-nwsmtp-smtp-production-main-64.vla.yp-c.yandex.net (mail-nwsmtp-smtp-production-main-64.vla.yp-c.yandex.net [IPv6:2a02:6b8:c1f:1492:0:640:cd24:0]) by forward102a.mail.yandex.net (Yandex) with ESMTP id 628F1608F6; Mon, 27 Nov 2023 18:00:00 +0300 (MSK) Received: by mail-nwsmtp-smtp-production-main-64.vla.yp-c.yandex.net (smtp/Yandex) with ESMTPSA id xxUYkABcsa60-j97w3XwR; Mon, 27 Nov 2023 18:00:00 +0300 X-Yandex-Fwd: 1 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=yandex.ru; s=mail; t=1701097200; bh=vJObKaWIE7oscY8SvaCxBGhWiswWq6kWoCCmp134KWU=; h=Message-ID:Date:Cc:Subject:To:From; b=wb5OPor979+hNvRwVMjpkkkxBIjL5VbaAfkhCffq0TwECanOQS71KNEO3+vlbWr3o kQOiIStdVRqYeM6dBJAHgyjKJQGHjC1j0LnTvMstzCwGbIAgjGXaiqijQrY76t0dmV amQkjLsgqR3wdkwwcd3ewhq0+QzXeJhaP38rO/rk= Authentication-Results: mail-nwsmtp-smtp-production-main-64.vla.yp-c.yandex.net; dkim=pass header.i=@yandex.ru From: Dmitry Antipov To: "Rafael J . Wysocki" Cc: Len Brown , Kees Cook , linux-acpi@vger.kernel.org, Dmitry Antipov Subject: [PATCH] pnp: acpi: fix fortify warning Date: Mon, 27 Nov 2023 17:58:50 +0300 Message-ID: <20231127145907.131160-1-dmantipov@yandex.ru> X-Mailer: git-send-email 2.43.0 Precedence: bulk X-Mailing-List: linux-acpi@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 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 --- drivers/pnp/pnpacpi/rsparser.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/drivers/pnp/pnpacpi/rsparser.c b/drivers/pnp/pnpacpi/rsparser.c index 4f05f610391b..af51f893525e 100644 --- a/drivers/pnp/pnpacpi/rsparser.c +++ b/drivers/pnp/pnpacpi/rsparser.c @@ -152,12 +152,12 @@ 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)); + memcpy(&range, vendor->byte_data, 16); - pnp_add_mem_resource(dev, start, start + length - 1, 0); + pnp_add_mem_resource(dev, range.start, range.start + + range.length - 1, 0); } }