From patchwork Tue Dec 18 11:03:31 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: =?utf-8?q?Philippe_Mathieu-Daud=C3=A9?= X-Patchwork-Id: 10735419 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id A7ABF13BF for ; Tue, 18 Dec 2018 11:15:52 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 95BAA2A475 for ; Tue, 18 Dec 2018 11:15:52 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 890772A4ED; Tue, 18 Dec 2018 11:15:52 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.9 required=2.0 tests=BAYES_00,MAILING_LIST_MULTI, RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from lists.gnu.org (lists.gnu.org [208.118.235.17]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id 07E582A475 for ; Tue, 18 Dec 2018 11:15:52 +0000 (UTC) Received: from localhost ([::1]:53153 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1gZDLr-0007ED-AI for patchwork-qemu-devel@patchwork.kernel.org; Tue, 18 Dec 2018 06:15:51 -0500 Received: from eggs.gnu.org ([2001:4830:134:3::10]:41248) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1gZDEj-00015C-P0 for qemu-devel@nongnu.org; Tue, 18 Dec 2018 06:08:32 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1gZDB6-0000FI-4z for qemu-devel@nongnu.org; Tue, 18 Dec 2018 06:04:45 -0500 Received: from mx1.redhat.com ([209.132.183.28]:57066) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1gZDB0-0000Ai-5o; Tue, 18 Dec 2018 06:04:38 -0500 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.phx2.redhat.com [10.5.11.13]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 4DFCB8E3D6; Tue, 18 Dec 2018 11:04:37 +0000 (UTC) Received: from x1w.redhat.com (unknown [10.40.205.65]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 67943608C2; Tue, 18 Dec 2018 11:04:04 +0000 (UTC) From: =?utf-8?q?Philippe_Mathieu-Daud=C3=A9?= To: qemu-devel@nongnu.org Date: Tue, 18 Dec 2018 12:03:31 +0100 Message-Id: <20181218110333.22558-2-philmd@redhat.com> In-Reply-To: <20181218110333.22558-1-philmd@redhat.com> References: <20181218110333.22558-1-philmd@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.13 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.25]); Tue, 18 Dec 2018 11:04:37 +0000 (UTC) X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] [fuzzy] X-Received-From: 209.132.183.28 Subject: [Qemu-devel] [PATCH v2 1/3] hw/acpi: Replace strncpy() by strpadcpy(pad='\0') X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: "Michael S. Tsirkin" , Jeff Cody , Paolo Bonzini , Ben Pye , qemu-block@nongnu.org, Juan Quintela , David Hildenbrand , Markus Armbruster , =?utf-8?q?Marc-Andr=C3=A9_Lureau?= , =?utf-8?q?Philippe_Mathieu-Daud=C3=A9?= , Thomas Huth , Stefan Weil , 1803872@bugs.launchpad.net, "Dr. David Alan Gilbert" , =?utf-8?q?C=C3=A9dric_Le_Goater?= , Liu Yuan , David Gibson , Kevin Wolf , Max Reitz , Howard Spoelstra , Igor Mammedov Errors-To: qemu-devel-bounces+patchwork-qemu-devel=patchwork.kernel.org@nongnu.org Sender: "Qemu-devel" X-Virus-Scanned: ClamAV using ClamSMTP From: Marc-André Lureau GCC 8 added a -Wstringop-truncation warning: The -Wstringop-truncation warning added in GCC 8.0 via r254630 for bug 81117 is specifically intended to highlight likely unintended uses of the strncpy function that truncate the terminating NUL character from the source string. This new warning leads to compilation failures: CC hw/acpi/core.o In function 'acpi_table_install', inlined from 'acpi_table_add' at qemu/hw/acpi/core.c:296:5: qemu/hw/acpi/core.c:184:9: error: 'strncpy' specified bound 4 equals destination size [-Werror=stringop-truncation] strncpy(ext_hdr->sig, hdrs->sig, sizeof ext_hdr->sig); ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ make: *** [qemu/rules.mak:69: hw/acpi/core.o] Error 1 The ACPI tables don't require the strings to be NUL-terminated, therefore strncpy is the right function to use here. We could add a #pragma GCC diagnostic ignored "-Wstringop-truncation" around, disable the warning globally using -Wno-stringop-truncation, but since QEMU provides the strpadcpy() which does the same purpose, simply use it to avoid the annoying warning. Signed-off-by: Marc-André Lureau Reviewed-by: Eric Blake Reviewed-by: Philippe Mathieu-Daudé [PMD: reword commit subject and description] Signed-off-by: Philippe Mathieu-Daudé Reviewed-by: Igor Mammedov --- hw/acpi/aml-build.c | 6 ++++-- hw/acpi/core.c | 13 +++++++------ 2 files changed, 11 insertions(+), 8 deletions(-) diff --git a/hw/acpi/aml-build.c b/hw/acpi/aml-build.c index 1e43cd736d..397833462a 100644 --- a/hw/acpi/aml-build.c +++ b/hw/acpi/aml-build.c @@ -24,6 +24,7 @@ #include "hw/acpi/aml-build.h" #include "qemu/bswap.h" #include "qemu/bitops.h" +#include "qemu/cutils.h" #include "sysemu/numa.h" static GArray *build_alloc_array(void) @@ -1532,13 +1533,14 @@ build_header(BIOSLinker *linker, GArray *table_data, h->revision = rev; if (oem_id) { - strncpy((char *)h->oem_id, oem_id, sizeof h->oem_id); + strpadcpy((char *)h->oem_id, sizeof h->oem_id, oem_id, '\0'); } else { memcpy(h->oem_id, ACPI_BUILD_APPNAME6, 6); } if (oem_table_id) { - strncpy((char *)h->oem_table_id, oem_table_id, sizeof(h->oem_table_id)); + strpadcpy((char *)h->oem_table_id, sizeof(h->oem_table_id), + oem_table_id, '\0'); } else { memcpy(h->oem_table_id, ACPI_BUILD_APPNAME4, 4); memcpy(h->oem_table_id + 4, sig, 4); diff --git a/hw/acpi/core.c b/hw/acpi/core.c index aafdc61648..6e8f4e5713 100644 --- a/hw/acpi/core.c +++ b/hw/acpi/core.c @@ -31,6 +31,7 @@ #include "qapi/qapi-visit-misc.h" #include "qemu/error-report.h" #include "qemu/option.h" +#include "qemu/cutils.h" struct acpi_table_header { uint16_t _length; /* our length, not actual part of the hdr */ @@ -181,7 +182,7 @@ static void acpi_table_install(const char unsigned *blob, size_t bloblen, ext_hdr->_length = cpu_to_le16(acpi_payload_size); if (hdrs->has_sig) { - strncpy(ext_hdr->sig, hdrs->sig, sizeof ext_hdr->sig); + strpadcpy(ext_hdr->sig, sizeof ext_hdr->sig, hdrs->sig, '\0'); ++changed_fields; } @@ -200,12 +201,12 @@ static void acpi_table_install(const char unsigned *blob, size_t bloblen, ext_hdr->checksum = 0; if (hdrs->has_oem_id) { - strncpy(ext_hdr->oem_id, hdrs->oem_id, sizeof ext_hdr->oem_id); + strpadcpy(ext_hdr->oem_id, sizeof ext_hdr->oem_id, hdrs->oem_id, '\0'); ++changed_fields; } if (hdrs->has_oem_table_id) { - strncpy(ext_hdr->oem_table_id, hdrs->oem_table_id, - sizeof ext_hdr->oem_table_id); + strpadcpy(ext_hdr->oem_table_id, sizeof ext_hdr->oem_table_id, + hdrs->oem_table_id, '\0'); ++changed_fields; } if (hdrs->has_oem_rev) { @@ -213,8 +214,8 @@ static void acpi_table_install(const char unsigned *blob, size_t bloblen, ++changed_fields; } if (hdrs->has_asl_compiler_id) { - strncpy(ext_hdr->asl_compiler_id, hdrs->asl_compiler_id, - sizeof ext_hdr->asl_compiler_id); + strpadcpy(ext_hdr->asl_compiler_id, sizeof ext_hdr->asl_compiler_id, + hdrs->asl_compiler_id, '\0'); ++changed_fields; } if (hdrs->has_asl_compiler_rev) {