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=-3.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT 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 5CD5CC4321D for ; Thu, 23 Aug 2018 08:58:29 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 1B0BF2084A for ; Thu, 23 Aug 2018 08:58:29 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 1B0BF2084A Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=linuxfoundation.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729740AbeHWM1I (ORCPT ); Thu, 23 Aug 2018 08:27:08 -0400 Received: from mail.linuxfoundation.org ([140.211.169.12]:52924 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726081AbeHWM1H (ORCPT ); Thu, 23 Aug 2018 08:27:07 -0400 Received: from localhost (5355525A.cm-6-6b.dynamic.ziggo.nl [83.85.82.90]) by mail.linuxfoundation.org (Postfix) with ESMTPSA id 1B7A4C83; Thu, 23 Aug 2018 08:58:24 +0000 (UTC) From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, David Laight , Taeung Song , "David S. Miller" , Daniel Borkmann , Sasha Levin Subject: [PATCH 4.17 189/324] samples/bpf: Check the error of write() and read() Date: Thu, 23 Aug 2018 09:54:15 +0200 Message-Id: <20180823075005.620304410@linuxfoundation.org> X-Mailer: git-send-email 2.18.0 In-Reply-To: <20180823074955.885811006@linuxfoundation.org> References: <20180823074955.885811006@linuxfoundation.org> User-Agent: quilt/0.65 X-stable: review MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 4.17-stable review patch. If anyone has any objections, please let me know. ------------------ From: Taeung Song [ Upstream commit 02a2f000a3629274bfad60bfc4de9edec49e63e7 ] test_task_rename() and test_urandom_read() can be failed during write() and read(), So check the result of them. Reviewed-by: David Laight Signed-off-by: Taeung Song Acked-by: David S. Miller Signed-off-by: Daniel Borkmann Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman --- samples/bpf/test_overhead_user.c | 19 +++++++++++++++---- 1 file changed, 15 insertions(+), 4 deletions(-) --- a/samples/bpf/test_overhead_user.c +++ b/samples/bpf/test_overhead_user.c @@ -6,6 +6,7 @@ */ #define _GNU_SOURCE #include +#include #include #include #include @@ -44,8 +45,13 @@ static void test_task_rename(int cpu) exit(1); } start_time = time_get_ns(); - for (i = 0; i < MAX_CNT; i++) - write(fd, buf, sizeof(buf)); + for (i = 0; i < MAX_CNT; i++) { + if (write(fd, buf, sizeof(buf)) < 0) { + printf("task rename failed: %s\n", strerror(errno)); + close(fd); + return; + } + } printf("task_rename:%d: %lld events per sec\n", cpu, MAX_CNT * 1000000000ll / (time_get_ns() - start_time)); close(fd); @@ -63,8 +69,13 @@ static void test_urandom_read(int cpu) exit(1); } start_time = time_get_ns(); - for (i = 0; i < MAX_CNT; i++) - read(fd, buf, sizeof(buf)); + for (i = 0; i < MAX_CNT; i++) { + if (read(fd, buf, sizeof(buf)) < 0) { + printf("failed to read from /dev/urandom: %s\n", strerror(errno)); + close(fd); + return; + } + } printf("urandom_read:%d: %lld events per sec\n", cpu, MAX_CNT * 1000000000ll / (time_get_ns() - start_time)); close(fd);