From patchwork Sun Apr 24 21:15:36 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Colin Ian King X-Patchwork-Id: 565658 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 AB4CDC433F5 for ; Sun, 24 Apr 2022 21:15:45 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233980AbiDXVSn (ORCPT ); Sun, 24 Apr 2022 17:18:43 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:45452 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233662AbiDXVSl (ORCPT ); Sun, 24 Apr 2022 17:18:41 -0400 Received: from mail-wr1-x42a.google.com (mail-wr1-x42a.google.com [IPv6:2a00:1450:4864:20::42a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id EEF8213CD2; Sun, 24 Apr 2022 14:15:38 -0700 (PDT) Received: by mail-wr1-x42a.google.com with SMTP id w4so18231441wrg.12; Sun, 24 Apr 2022 14:15:38 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=QLCz1aEPZpTPZGtnpY3lHtJPFa6xwSRJK3O6rkL3K5c=; b=aCkTg93Kczt9m6C0yGFdto0l0p1yyEUzTPppKeDoSVWvQRERuAsM6KmuUbXV13pnrF Ftxp6eK8GcyYBiLbl79e3Aao75qo+6/wUyemedovZToO9dx4TnDZvHCJdAn4SsMdj+0w 43Xy7RxetQ3kuPR0H6+b6N6I+BZy+6oAMaEyQaq8LYkSrZSnz/4A0uk40HrtJi1dBoBV uwjC5VmshX7W0tC9pnXXxII6dXgfSb449cYLqRo8yeZRsfnPheAA0fz4bODERkiWLdyt ZfVirEV/P7A+iSmK46RivLw7mjB2mRseKAOkACDdzq71CY2aM0TgbXnJFauYlZPYbYAZ ufxg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=QLCz1aEPZpTPZGtnpY3lHtJPFa6xwSRJK3O6rkL3K5c=; b=B41/ExnDz+bCJgtnJ286vQHoRTE97YWmsSXeA8REh/SdtOelTQnphyzZwmp0CuxNSK 30GJYJ3K8Vw7fBZaUXrioXOe64NxBq6qvFAgfi5vU23OwmPmDHhlCk9skXkG9z9VJfhA 5C9DOXOKLPnfzViNqSOLfVLdS6Qm3AUj9aYqZfczhSHGz/IiJGoH4VYcqC5PoEATi4NL vuvH79VLiRuzMIA3nk5gIMrUM6coSv07qtdbOuVaRGv4MDQ5icnX2KuUCb5MPuRtUuY1 dBKOjVhCGTisGkCba65cKfSzg/UNAYFxvobgiTjaf4yMBFc8shNQFA73ChMdJADgVEs0 N2lg== X-Gm-Message-State: AOAM531orNzzFAJOMQva5OHLJNbivpZ8zSRHUCPBEUJmJiIqjOoyLyxj te1x3RoCE+F/hgjnMXJUFPY= X-Google-Smtp-Source: ABdhPJz/FOFaeagHS5EO2XRc0+fKcdVmCWhnmahvPolqKQRCXrZWtIDoi0pRkc8kI5dw3Gh1Fp25tg== X-Received: by 2002:a5d:6d0d:0:b0:20a:d741:6949 with SMTP id e13-20020a5d6d0d000000b0020ad7416949mr4522984wrq.312.1650834937597; Sun, 24 Apr 2022 14:15:37 -0700 (PDT) Received: from localhost (cpc154979-craw9-2-0-cust193.16-3.cable.virginm.net. [80.193.200.194]) by smtp.gmail.com with ESMTPSA id bi7-20020a05600c3d8700b0038eb78569aasm9571468wmb.20.2022.04.24.14.15.36 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sun, 24 Apr 2022 14:15:37 -0700 (PDT) From: Colin Ian King To: Fenghua Yu , Reinette Chatre , Shuah Khan , Babu Moger , Sai Praneeth Prakhya , linux-kselftest@vger.kernel.org Cc: kernel-janitors@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH] selftests/resctrl: Fix null pointer dereference on open failed Date: Sun, 24 Apr 2022 22:15:36 +0100 Message-Id: <20220424211536.1373878-1-colin.i.king@gmail.com> X-Mailer: git-send-email 2.35.1 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-kselftest@vger.kernel.org Currently if opening /dev/null fails to open then file pointer fp is null and further access to fp via fprintf will cause a null pointer dereference. Fix this by returning a negative error value when a null fp is detected. Fixes: a2561b12fe39 ("selftests/resctrl: Add built in benchmark") Signed-off-by: Colin Ian King --- tools/testing/selftests/resctrl/fill_buf.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/tools/testing/selftests/resctrl/fill_buf.c b/tools/testing/selftests/resctrl/fill_buf.c index 51e5cf22632f..56ccbeae0638 100644 --- a/tools/testing/selftests/resctrl/fill_buf.c +++ b/tools/testing/selftests/resctrl/fill_buf.c @@ -121,8 +121,10 @@ static int fill_cache_read(unsigned char *start_ptr, unsigned char *end_ptr, /* Consume read result so that reading memory is not optimized out. */ fp = fopen("/dev/null", "w"); - if (!fp) + if (!fp) { perror("Unable to write to /dev/null"); + return -1; + } fprintf(fp, "Sum: %d ", ret); fclose(fp);