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=-6.8 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_PASS,URIBL_BLOCKED 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 CC3C6C4360F for ; Fri, 5 Apr 2019 14:33:50 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 9707C206DD for ; Fri, 5 Apr 2019 14:33:50 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="XawXQLC6" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731102AbfDEOdu (ORCPT ); Fri, 5 Apr 2019 10:33:50 -0400 Received: from mail-wr1-f65.google.com ([209.85.221.65]:42600 "EHLO mail-wr1-f65.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726594AbfDEOdu (ORCPT ); Fri, 5 Apr 2019 10:33:50 -0400 Received: by mail-wr1-f65.google.com with SMTP id g3so8274380wrx.9 for ; Fri, 05 Apr 2019 07:33:49 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=sender:date:from:to:cc:subject:in-reply-to:message-id:references :user-agent:mime-version; bh=tay2HgwzrulyG4rw5zVXJVBK5f04A1peT50eDrQWCc8=; b=XawXQLC6Ha2FOBplNUG0kDpxs+iWk4y9YHATdAFtp0e4AxJz25rgRkhvIQb06wBlDK NBpB5ozd6ThTD8828cbJeZHIo/tGjTJX8usWg26121a3GrAvJh9kVsB/OvgwVP632MNw clo1DP2MOMuGR+Oz2Z1Z4W8eBRgk2awnoRw9CNgsbr+zZ6QQio7OrTPaP8yvMKsK1usz dQ9JDpO8AJppjfLOYf+h7yKggmzO6E5m4S8PjEY2S5vEy/JulbKgbiLD9QsBancAHlol hUd2QXWXIx2DoSbh6woy2WkV+6ErmIBAnOLsReFqNGDVa3dQQPDjcqI4cESVc+LaN9E2 jcWw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:date:from:to:cc:subject:in-reply-to :message-id:references:user-agent:mime-version; bh=tay2HgwzrulyG4rw5zVXJVBK5f04A1peT50eDrQWCc8=; b=lMO5JPjA3hwe7Z2kIY0WTSNoOGT4TP6ch/GClgFT64u4QpcETdHrlXSYCrC6GgG3g+ 9p1Wbi23n5SIMADXxVvO8ZOr4KUeED0py00navx1NghBLlAuuE/OUjSd+CcoZGs85R9M rTnnMEIdqmF8u1epROMnou9FUKKmKFyvaLt6sTk//4t6d0RUarRC3bHFLxX2aT/Eys52 gttDw6h1oDzxQa1JXLaAq5W9XxQqD5XCrjRNHWSmqpxULrMBIkEaG1hdu9gzvYNkKbQq qeIA+V9mvNBMdjIpbzm0HK24lktuRW2EY6clgKjFv2oyDs+tWhKnLr/SS1Y6CsHbkD/b JYQg== X-Gm-Message-State: APjAAAVuAnEObiQAwKgr4L1EYb/WN08QAjficJbELOfIiCxFoenGKZbA 5DbRSvTPxrPCj7KkES/mK8k= X-Google-Smtp-Source: APXvYqy29P8Bhon2Vid32WQkr3mvr80RGKvzJJTnNkjK31KidOj9c0ZCv56Gr4w40bj2DM+biCtzfw== X-Received: by 2002:adf:fecb:: with SMTP id q11mr9348500wrs.252.1554474828371; Fri, 05 Apr 2019 07:33:48 -0700 (PDT) Received: from planxty ([2a02:8108:1700:1960:91dd:e2f9:ed05:ee2b]) by smtp.gmail.com with ESMTPSA id j3sm47255965wre.51.2019.04.05.07.33.45 (version=TLS1_3 cipher=AEAD-AES256-GCM-SHA384 bits=256/256); Fri, 05 Apr 2019 07:33:47 -0700 (PDT) Date: Fri, 5 Apr 2019 16:33:33 +0200 (CEST) From: John Kacur X-X-Sender: jkacur@planxty To: Kurt Kanzenbach cc: Clark Williams , rt-users Subject: Re: [PATCH 1/4] rt-tests: cyclicdeadline: fix segmentation fault on close In-Reply-To: <20190404134814.13376-2-kurt@linutronix.de> Message-ID: References: <20190404134814.13376-1-kurt@linutronix.de> <20190404134814.13376-2-kurt@linutronix.de> User-Agent: Alpine 2.21 (LFD 202 2017-01-01) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Sender: linux-rt-users-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-rt-users@vger.kernel.org On Thu, 4 Apr 2019, Kurt Kanzenbach wrote: > The current code generates a segmentation fault in the last free() call. > > $ sudo ./cyclicdeadline > Using all CPUS > /sys/kernel/debug/sched_features: Success > interval: 600:1000 > Tested at 5us of 600us > deadline thread 2963 > thread[2963] runtime=600us deadline=1000us > main thread 2962 > fail 2 0 > T: 0 ( 2963) I:1000 C: 1268 Min: 7 Act: 55 Avg: 56 Max: 256 > [1] 2961 segmentation fault sudo ./cyclicdeadline > > This is caused by a buffer overflow in setup_ftrace_marker(). The appended > string is 21 not 14 characters wide. Fix it by using strlen() like the other > function do. > > Signed-off-by: Kurt Kanzenbach > --- > src/sched_deadline/cyclicdeadline.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/src/sched_deadline/cyclicdeadline.c b/src/sched_deadline/cyclicdeadline.c > index 08460107c464..303b5e96647a 100644 > --- a/src/sched_deadline/cyclicdeadline.c > +++ b/src/sched_deadline/cyclicdeadline.c > @@ -283,7 +283,7 @@ static void setup_ftrace_marker(void) > { > struct stat st; > const char *debugfs = find_debugfs(); > - char files[strlen(debugfs) + 14]; > + char files[strlen(debugfs) + strlen("/tracing/trace_marker") + 1]; > int ret; > > if (strlen(debugfs) == 0) > -- > 2.11.0 > > Signed-off-by: John Kacur