From patchwork Wed May 24 08:47:24 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: =?utf-8?q?C=C3=A9dric_Le_Goater?= X-Patchwork-Id: 13253533 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id A0C12C7EE23 for ; Wed, 24 May 2023 08:48:09 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1q1k9s-0001i0-6e; Wed, 24 May 2023 04:47:48 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1q1k9q-0001fP-0E for qemu-devel@nongnu.org; Wed, 24 May 2023 04:47:46 -0400 Received: from gandalf.ozlabs.org ([150.107.74.76]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1q1k9o-0002N3-9f for qemu-devel@nongnu.org; Wed, 24 May 2023 04:47:45 -0400 Received: from gandalf.ozlabs.org (gandalf.ozlabs.org [150.107.74.76]) by gandalf.ozlabs.org (Postfix) with ESMTP id 4QR4ZM24xZz4x4S; Wed, 24 May 2023 18:47:39 +1000 (AEST) Received: from authenticated.ozlabs.org (localhost [127.0.0.1]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) by mail.ozlabs.org (Postfix) with ESMTPSA id 4QR4ZK0D88z4x3g; Wed, 24 May 2023 18:47:36 +1000 (AEST) From: =?utf-8?q?C=C3=A9dric_Le_Goater?= To: qemu-devel@nongnu.org Cc: Richard Henderson , Alex Williamson , Akihiko Odaki , =?utf-8?q?Philippe_Mathieu-Daud?= =?utf-8?q?=C3=A9?= , =?utf-8?q?C=C3=A9dric_Le_Goater?= Subject: [PULL 2/2] util/vfio-helpers: Use g_file_read_link() Date: Wed, 24 May 2023 10:47:24 +0200 Message-Id: <20230524084724.2511267-3-clg@redhat.com> X-Mailer: git-send-email 2.40.1 In-Reply-To: <20230524084724.2511267-1-clg@redhat.com> References: <20230524084724.2511267-1-clg@redhat.com> MIME-Version: 1.0 Received-SPF: pass client-ip=150.107.74.76; envelope-from=SRS0=pqJs=BN=redhat.com=clg@ozlabs.org; helo=gandalf.ozlabs.org X-Spam_score_int: -16 X-Spam_score: -1.7 X-Spam_bar: - X-Spam_report: (-1.7 / 5.0 requ) BAYES_00=-1.9, HEADER_FROM_DIFFERENT_DOMAINS=0.249, SPF_HELO_PASS=-0.001, SPF_PASS=-0.001, T_SCC_BODY_TEXT_LINE=-0.01 autolearn=no autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org From: Akihiko Odaki When _FORTIFY_SOURCE=2, glibc version is 2.35, and GCC version is 12.1.0, the compiler complains as follows: In file included from /usr/include/features.h:490, from /usr/include/bits/libc-header-start.h:33, from /usr/include/stdint.h:26, from /usr/lib/gcc/aarch64-unknown-linux-gnu/12.1.0/include/stdint.h:9, from /home/alarm/q/var/qemu/include/qemu/osdep.h:94, from ../util/vfio-helpers.c:13: In function 'readlink', inlined from 'sysfs_find_group_file' at ../util/vfio-helpers.c:116:9, inlined from 'qemu_vfio_init_pci' at ../util/vfio-helpers.c:326:18, inlined from 'qemu_vfio_open_pci' at ../util/vfio-helpers.c:517:9: /usr/include/bits/unistd.h:119:10: error: argument 2 is null but the corresponding size argument 3 value is 4095 [-Werror=nonnull] 119 | return __glibc_fortify (readlink, __len, sizeof (char), | ^~~~~~~~~~~~~~~ This error implies the allocated buffer can be NULL. Use g_file_read_link(), which allocates buffer automatically to avoid the error. Signed-off-by: Akihiko Odaki Reviewed-by: Philippe Mathieu-Daudé Reviewed-by: Cédric Le Goater Signed-off-by: Cédric Le Goater --- util/vfio-helpers.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) diff --git a/util/vfio-helpers.c b/util/vfio-helpers.c index 2d8af38f886a..f8bab46c68fa 100644 --- a/util/vfio-helpers.c +++ b/util/vfio-helpers.c @@ -106,15 +106,17 @@ struct QEMUVFIOState { */ static char *sysfs_find_group_file(const char *device, Error **errp) { + g_autoptr(GError) gerr = NULL; char *sysfs_link; char *sysfs_group; char *p; char *path = NULL; sysfs_link = g_strdup_printf("/sys/bus/pci/devices/%s/iommu_group", device); - sysfs_group = g_malloc0(PATH_MAX); - if (readlink(sysfs_link, sysfs_group, PATH_MAX - 1) == -1) { - error_setg_errno(errp, errno, "Failed to find iommu group sysfs path"); + sysfs_group = g_file_read_link(sysfs_link, &gerr); + if (gerr) { + error_setg(errp, "Failed to find iommu group sysfs path: %s", + gerr->message); goto out; } p = strrchr(sysfs_group, '/');