From patchwork Tue Nov 1 14:23:07 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Rong Tao X-Patchwork-Id: 620985 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 05627C433FE for ; Tue, 1 Nov 2022 14:23:23 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230241AbiKAOXW (ORCPT ); Tue, 1 Nov 2022 10:23:22 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:41074 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229766AbiKAOXV (ORCPT ); Tue, 1 Nov 2022 10:23:21 -0400 Received: from out162-62-57-210.mail.qq.com (out162-62-57-210.mail.qq.com [162.62.57.210]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id ACA121B1FB; Tue, 1 Nov 2022 07:23:17 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=foxmail.com; s=s201512; t=1667312593; bh=l57fPtvVIgXTiYLMlFVCC6EXs6IDtJKDnxNvjdOUkcM=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=dG4TA+4Bll7492rMsS8WJaix0eoOwd7HqJaAylQ9majA9lMWH3lAdDOHRgomRnAkx p7gkd8+tclRIsPHJiVIpcZWie70dvu8i3VBT42+H8c6GYIR1/No4zU6Zrp2E/t+vGO dLTymhQKQvxhQ7X4h5iBGnzbLRC7wWi94CMGk8x8= Received: from localhost.localdomain ([111.199.189.86]) by newxmesmtplogicsvrszb6-0.qq.com (NewEsmtp) with SMTP id 5C8A8617; Tue, 01 Nov 2022 22:23:08 +0800 X-QQ-mid: xmsmtpt1667312588tydmkk56a Message-ID: X-QQ-XMAILINFO: NkHKfw09D6j8nya1MpOLbHO6M3R7kUmTeJKqU8bBsXqWRReOWDSDVWI6V8tWhN YGrHWs/ZqniKBScePxRhbqgGs190QduRHvk0+3ORugItPyo+KjTrVkAwfZFRPoHaE8g6aTEOsKu/ DtH3P2KV1Rvi4Zr3KSKl6Crl6xCDX/qiUJ62/aimuZao6phXPLed2obw86eoOAMtKZZmVRVHBl9s GUsWE0XQH2eFlp3KCVkymh5ZzPdiB6BsmwCY3x3g6XDmdhEtSkKrdzGeholKfA5WJx58BE/lSMFz h0G5vEkQ2E7ICILcIqvMxk6K8+9cgRp8bGr5JETqN7v7rpa2sphVrCpS6m5u1Lxjl18KeTaRBK9y Syt6VMCfnctkcFAOLumCvwKbXj6FbJYkzEFOWzvktbWNbskSG7JSc256E+tGIQVlsmjKjTubmN/Z hic6em+Wmub3kqm8Oo0NutB2do6AcJ0PjYDd0Rh3cqc2tqx/Y3BiAs6ISjGvBHPte/ev43eU7CEc AKQR56nHD0HgCvOnWgBlYKKNxM3qC2DdB6a/oOloZI8i6WVqfayjLJ/hO8wfdM6UCNOdvNkhhtSc WBOMPqRpICZQd/WWJmhzNLRCe9MQsHZSg0/C8UFogHQ2zZNjISA++DtrwGhB8RTLvvRZepfka+GK 45NQm2uC8syIUepLvCMzZ0jf3DpHEX7U+5uyhzO/dH8Fv7MQKs7k8YlZigI/QJe8BIb2fA0T+al/ m0WJdbe5m6LEaRZcQgaQlYrnlTkzGZmogl367ToL5MAILCJu4itC7GBh1voxTYzlua4GUrQYDsqI Niv4X/6Hys/q5uEXXqgjN6eLTo6qrPisOvdQkVp0zTXN2rd52Yhf48rXuqjdCFaRWbJb0sywfEda vuqFjBZDGMdk1E6CyXCz9K+R8GJSyHjRi93e1WoOvUtDyPMxBKfzClOfC90AIl3dlYNG0K1bb6WO 9hRHCW4gftV8RBiHNIv6KcqXI7XA74KNDpGFaOXhhIiP9a6kgiYio++dncugKNo81BVCFy5pTbqM o7M0PjNEQczUTFfkRI From: Rong Tao To: daniel@iogearbox.net Cc: andrii.nakryiko@gmail.com, andrii@kernel.org, ast@kernel.org, bpf@vger.kernel.org, david.laight@aculab.com, haoluo@google.com, john.fastabend@gmail.com, jolsa@kernel.org, kpsingh@kernel.org, linux-kernel@vger.kernel.org, linux-kselftest@vger.kernel.org, martin.lau@linux.dev, mykolal@fb.com, rongtao@cestc.cn, rtoax@foxmail.com, sdf@google.com, shuah@kernel.org, song@kernel.org, yhs@fb.com Subject: [PATCH bpf-next] selftests/bpf: Fix strncpy() fortify warning Date: Tue, 1 Nov 2022 22:23:07 +0800 X-OQ-MSGID: <20221101142307.19414-1-rtoax@foxmail.com> X-Mailer: git-send-email 2.31.1 In-Reply-To: References: MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-kselftest@vger.kernel.org From: Rong Tao move libbpf_strlcpy() to bpf_util.h, and replace strncpy() with libbpf_strlcpy(), fix compile warning. Compile samples/bpf, warning: $ cd samples/bpf $ make ... cgroup_helpers.c: In function ‘__enable_controllers’: cgroup_helpers.c:80:17: warning: ‘strncpy’ specified bound 4097 equals destination size [-Wstringop-truncation] 80 | strncpy(enable, controllers, sizeof(enable)); | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Signed-off-by: Rong Tao --- tools/testing/selftests/bpf/bpf_util.h | 19 +++++++++++++++++++ tools/testing/selftests/bpf/cgroup_helpers.c | 3 ++- tools/testing/selftests/bpf/xsk.c | 20 +------------------- 3 files changed, 22 insertions(+), 20 deletions(-) diff --git a/tools/testing/selftests/bpf/bpf_util.h b/tools/testing/selftests/bpf/bpf_util.h index a3352a64c067..bf78212ff6e9 100644 --- a/tools/testing/selftests/bpf/bpf_util.h +++ b/tools/testing/selftests/bpf/bpf_util.h @@ -20,6 +20,25 @@ static inline unsigned int bpf_num_possible_cpus(void) return possible_cpus; } +/* Copy up to sz - 1 bytes from zero-terminated src string and ensure that dst + * is zero-terminated string no matter what (unless sz == 0, in which case + * it's a no-op). It's conceptually close to FreeBSD's strlcpy(), but differs + * in what is returned. Given this is internal helper, it's trivial to extend + * this, when necessary. Use this instead of strncpy inside libbpf source code. + */ +static inline void libbpf_strlcpy(char *dst, const char *src, size_t sz) +{ + size_t i; + + if (sz == 0) + return; + + sz--; + for (i = 0; i < sz && src[i]; i++) + dst[i] = src[i]; + dst[i] = '\0'; +} + #define __bpf_percpu_val_align __attribute__((__aligned__(8))) #define BPF_DECLARE_PERCPU(type, name) \ diff --git a/tools/testing/selftests/bpf/cgroup_helpers.c b/tools/testing/selftests/bpf/cgroup_helpers.c index e914cc45b766..e33b70e509da 100644 --- a/tools/testing/selftests/bpf/cgroup_helpers.c +++ b/tools/testing/selftests/bpf/cgroup_helpers.c @@ -13,6 +13,7 @@ #include #include "cgroup_helpers.h" +#include "bpf_util.h" /* * To avoid relying on the system setup, when setup_cgroup_env is called @@ -77,7 +78,7 @@ static int __enable_controllers(const char *cgroup_path, const char *controllers enable[len] = 0; close(fd); } else { - strncpy(enable, controllers, sizeof(enable)); + libbpf_strlcpy(enable, controllers, sizeof(enable)); } snprintf(path, sizeof(path), "%s/cgroup.subtree_control", cgroup_path); diff --git a/tools/testing/selftests/bpf/xsk.c b/tools/testing/selftests/bpf/xsk.c index 0b3ff49c740d..cf6e9ab37b1b 100644 --- a/tools/testing/selftests/bpf/xsk.c +++ b/tools/testing/selftests/bpf/xsk.c @@ -33,6 +33,7 @@ #include #include #include "xsk.h" +#include "bpf_util.h" #ifndef SOL_XDP #define SOL_XDP 283 @@ -521,25 +522,6 @@ static int xsk_create_bpf_link(struct xsk_socket *xsk) return 0; } -/* Copy up to sz - 1 bytes from zero-terminated src string and ensure that dst - * is zero-terminated string no matter what (unless sz == 0, in which case - * it's a no-op). It's conceptually close to FreeBSD's strlcpy(), but differs - * in what is returned. Given this is internal helper, it's trivial to extend - * this, when necessary. Use this instead of strncpy inside libbpf source code. - */ -static inline void libbpf_strlcpy(char *dst, const char *src, size_t sz) -{ - size_t i; - - if (sz == 0) - return; - - sz--; - for (i = 0; i < sz && src[i]; i++) - dst[i] = src[i]; - dst[i] = '\0'; -} - static int xsk_get_max_queues(struct xsk_socket *xsk) { struct ethtool_channels channels = { .cmd = ETHTOOL_GCHANNELS };