From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([209.51.188.92]:36196) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1hEv6l-0002he-Gd for qemu-devel@nongnu.org; Fri, 12 Apr 2019 08:16:40 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1hEv6k-0004WN-JR for qemu-devel@nongnu.org; Fri, 12 Apr 2019 08:16:39 -0400 Received: from mx1.redhat.com ([209.132.183.28]:37740) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1hEv6k-0004W7-Cp for qemu-devel@nongnu.org; Fri, 12 Apr 2019 08:16:38 -0400 From: =?UTF-8?q?Daniel=20P=2E=20Berrang=C3=A9?= Date: Fri, 12 Apr 2019 13:16:23 +0100 Message-Id: <20190412121626.19829-3-berrange@redhat.com> In-Reply-To: <20190412121626.19829-1-berrange@redhat.com> References: <20190412121626.19829-1-berrange@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable Subject: [Qemu-devel] [PATCH v2 2/5] linux-user: avoid string truncation warnings in elf field copying List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: Laurent Vivier , Riku Voipio , Gerd Hoffmann , =?UTF-8?q?Daniel=20P=2E=20Berrang=C3=A9?= In file included from /usr/include/string.h:494, from include/qemu/osdep.h:101, from linux-user/elfload.c:2: In function =E2=80=98strncpy=E2=80=99, inlined from =E2=80=98fill_psinfo=E2=80=99 at linux-user/elfload.c:32= 08:12, inlined from =E2=80=98fill_note_info=E2=80=99 at linux-user/elfload.c= :3390:5, inlined from =E2=80=98elf_core_dump=E2=80=99 at linux-user/elfload.c:= 3539:9: /usr/include/bits/string_fortified.h:106:10: warning: =E2=80=98__builtin_= strncpy=E2=80=99 specified bound 16 equals destination size [-Wstringop-t= runcation] 106 | return __builtin___strncpy_chk (__dest, __src, __len, __bos (__= dest)); | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~= ~~~~~~ We don't require the field to be NUL terminated, so can just copy the lower of the string length and the target field size using memcpy. Signed-off-by: Daniel P. Berrang=C3=A9 --- linux-user/elfload.c | 10 ++++------ 1 file changed, 4 insertions(+), 6 deletions(-) diff --git a/linux-user/elfload.c b/linux-user/elfload.c index c1a26021f8..caa060f7b7 100644 --- a/linux-user/elfload.c +++ b/linux-user/elfload.c @@ -3180,6 +3180,7 @@ static int fill_psinfo(struct target_elf_prpsinfo *= psinfo, const TaskState *ts) { char *base_filename; unsigned int i, len; + size_t pathlen; =20 (void) memset(psinfo, 0, sizeof (*psinfo)); =20 @@ -3201,12 +3202,9 @@ static int fill_psinfo(struct target_elf_prpsinfo = *psinfo, const TaskState *ts) psinfo->pr_gid =3D getgid(); =20 base_filename =3D g_path_get_basename(ts->bprm->filename); - /* - * Using strncpy here is fine: at max-length, - * this field is not NUL-terminated. - */ - (void) strncpy(psinfo->pr_fname, base_filename, - sizeof(psinfo->pr_fname)); + pathlen =3D strlen(base_filename) + 1; + pathlen =3D MIN(pathlen, sizeof(psinfo->pr_fname)); + memcpy(psinfo->pr_fname, base_filename, pathlen); =20 g_free(base_filename); bswap_psinfo(psinfo); --=20 2.20.1 From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.9 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 8E01CC10F0E for ; Fri, 12 Apr 2019 12:18:44 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 617192077C for ; Fri, 12 Apr 2019 12:18:44 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 617192077C Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([127.0.0.1]:35476 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1hEv8l-0003sW-FM for qemu-devel@archiver.kernel.org; Fri, 12 Apr 2019 08:18:43 -0400 Received: from eggs.gnu.org ([209.51.188.92]:36196) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1hEv6l-0002he-Gd for qemu-devel@nongnu.org; Fri, 12 Apr 2019 08:16:40 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1hEv6k-0004WN-JR for qemu-devel@nongnu.org; Fri, 12 Apr 2019 08:16:39 -0400 Received: from mx1.redhat.com ([209.132.183.28]:37740) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1hEv6k-0004W7-Cp for qemu-devel@nongnu.org; Fri, 12 Apr 2019 08:16:38 -0400 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.phx2.redhat.com [10.5.11.14]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id B016930842B5; Fri, 12 Apr 2019 12:16:37 +0000 (UTC) Received: from localhost.localdomain.com (ovpn-112-27.ams2.redhat.com [10.36.112.27]) by smtp.corp.redhat.com (Postfix) with ESMTP id 9E1905D9CC; Fri, 12 Apr 2019 12:16:35 +0000 (UTC) From: =?UTF-8?q?Daniel=20P=2E=20Berrang=C3=A9?= To: qemu-devel@nongnu.org Date: Fri, 12 Apr 2019 13:16:23 +0100 Message-Id: <20190412121626.19829-3-berrange@redhat.com> In-Reply-To: <20190412121626.19829-1-berrange@redhat.com> References: <20190412121626.19829-1-berrange@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset="UTF-8" X-Scanned-By: MIMEDefang 2.79 on 10.5.11.14 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.40]); Fri, 12 Apr 2019 12:16:37 +0000 (UTC) Content-Transfer-Encoding: quoted-printable X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 209.132.183.28 Subject: [Qemu-devel] [PATCH v2 2/5] linux-user: avoid string truncation warnings in elf field copying 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: Riku Voipio , Laurent Vivier , Gerd Hoffmann Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" Message-ID: <20190412121623.1kmN5W3FbqQyxYDNCCJSrFAn4a6-KRbyBFdo7-XVTKE@z> In file included from /usr/include/string.h:494, from include/qemu/osdep.h:101, from linux-user/elfload.c:2: In function =E2=80=98strncpy=E2=80=99, inlined from =E2=80=98fill_psinfo=E2=80=99 at linux-user/elfload.c:32= 08:12, inlined from =E2=80=98fill_note_info=E2=80=99 at linux-user/elfload.c= :3390:5, inlined from =E2=80=98elf_core_dump=E2=80=99 at linux-user/elfload.c:= 3539:9: /usr/include/bits/string_fortified.h:106:10: warning: =E2=80=98__builtin_= strncpy=E2=80=99 specified bound 16 equals destination size [-Wstringop-t= runcation] 106 | return __builtin___strncpy_chk (__dest, __src, __len, __bos (__= dest)); | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~= ~~~~~~ We don't require the field to be NUL terminated, so can just copy the lower of the string length and the target field size using memcpy. Signed-off-by: Daniel P. Berrang=C3=A9 --- linux-user/elfload.c | 10 ++++------ 1 file changed, 4 insertions(+), 6 deletions(-) diff --git a/linux-user/elfload.c b/linux-user/elfload.c index c1a26021f8..caa060f7b7 100644 --- a/linux-user/elfload.c +++ b/linux-user/elfload.c @@ -3180,6 +3180,7 @@ static int fill_psinfo(struct target_elf_prpsinfo *= psinfo, const TaskState *ts) { char *base_filename; unsigned int i, len; + size_t pathlen; =20 (void) memset(psinfo, 0, sizeof (*psinfo)); =20 @@ -3201,12 +3202,9 @@ static int fill_psinfo(struct target_elf_prpsinfo = *psinfo, const TaskState *ts) psinfo->pr_gid =3D getgid(); =20 base_filename =3D g_path_get_basename(ts->bprm->filename); - /* - * Using strncpy here is fine: at max-length, - * this field is not NUL-terminated. - */ - (void) strncpy(psinfo->pr_fname, base_filename, - sizeof(psinfo->pr_fname)); + pathlen =3D strlen(base_filename) + 1; + pathlen =3D MIN(pathlen, sizeof(psinfo->pr_fname)); + memcpy(psinfo->pr_fname, base_filename, pathlen); =20 g_free(base_filename); bswap_psinfo(psinfo); --=20 2.20.1