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=-15.3 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_2 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 5D47FC11F68 for ; Tue, 29 Jun 2021 20:40:49 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 32D8161D70 for ; Tue, 29 Jun 2021 20:40:49 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235235AbhF2UnQ (ORCPT ); Tue, 29 Jun 2021 16:43:16 -0400 Received: from mail.kernel.org ([198.145.29.99]:48180 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234054AbhF2UnP (ORCPT ); Tue, 29 Jun 2021 16:43:15 -0400 Received: from oasis.local.home (cpe-66-24-58-225.stny.res.rr.com [66.24.58.225]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 18526613B4 for ; Tue, 29 Jun 2021 20:40:48 +0000 (UTC) Date: Tue, 29 Jun 2021 16:40:46 -0400 From: Steven Rostedt To: "linux-trace-devel@vger.kernel.org" Subject: [PATCH] libtracefs: Fix tracefs_event_enable/disable() to not have open regex Message-ID: <20210629164046.48f8b323@oasis.local.home> X-Mailer: Claws Mail 3.17.3 (GTK+ 2.24.33; x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-trace-devel@vger.kernel.org From: "Steven Rostedt (VMware)" Found that calling tracefs_event_enable/disable() will match all content of the passed in strings and not just what is passed in. That is, if you have two events, "open" and "open2", and call tracefs_event_enable(NULL, NULL, "open"); it will match both the "open" event as well as the "open2" event. This is because the regex is open ended. To fix this, add a '^' to the beginning of the match and a '$' to the end (if they do not already exist). Fixes: fc94d1a8 ("libtracefs: Add tracefs_event_enable/disable() API") Signed-off-by: Steven Rostedt (VMware) --- src/tracefs-events.c | 23 ++++++++++++++++++++++- 1 file changed, 22 insertions(+), 1 deletion(-) diff --git a/src/tracefs-events.c b/src/tracefs-events.c index 0fef64f..b6d3136 100644 --- a/src/tracefs-events.c +++ b/src/tracefs-events.c @@ -828,6 +828,26 @@ static int enable_disable_all(struct tracefs_instance *instance, return ret < 0 ? ret : 0; } +static int make_regex(regex_t *re, const char *match) +{ + int len = strlen(match); + char str[len + 3]; + char *p = &str[0]; + + if (!len || match[0] != '^') + *(p++) = '^'; + + strcpy(p, match); + p += len; + + if (!len || match[len-1] != '$') + *(p++) = '$'; + + *p = '\0'; + + return regcomp(re, str, REG_ICASE|REG_NOSUB); +} + static int event_enable_disable(struct tracefs_instance *instance, const char *system, const char *event, bool enable) @@ -847,12 +867,13 @@ static int event_enable_disable(struct tracefs_instance *instance, goto out_free; if (system) { + ret = make_regex(&system_re, system); ret = regcomp(&system_re, system, REG_ICASE|REG_NOSUB); if (ret < 0) goto out_free; } if (event) { - ret = regcomp(&event_re, event, REG_ICASE|REG_NOSUB); + ret = make_regex(&event_re, event); if (ret < 0) { if (system) regfree(&system_re); -- 2.29.2