From patchwork Thu Sep 7 02:47:15 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Steven Rostedt X-Patchwork-Id: 13376113 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 AA77EEE14D3 for ; Thu, 7 Sep 2023 02:47:52 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229507AbjIGCry (ORCPT ); Wed, 6 Sep 2023 22:47:54 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:38992 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239344AbjIGCry (ORCPT ); Wed, 6 Sep 2023 22:47:54 -0400 Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 2940619AF; Wed, 6 Sep 2023 19:47:51 -0700 (PDT) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 22C51C433A9; Thu, 7 Sep 2023 02:47:50 +0000 (UTC) Received: from rostedt by gandalf with local (Exim 4.96) (envelope-from ) id 1qe53s-000BK3-0s; Wed, 06 Sep 2023 22:48:04 -0400 Message-ID: <20230907024804.086679464@goodmis.org> User-Agent: quilt/0.66 Date: Wed, 06 Sep 2023 22:47:15 -0400 From: Steven Rostedt To: linux-kernel@vger.kernel.org, linux-trace-kernel@vger.kernel.org Cc: Masami Hiramatsu , Mark Rutland , Andrew Morton , Zheng Yejian , Naresh Kamboju , stable@vger.kernel.org Subject: [PATCH 5/6] tracing: Have option files inc the trace array ref count References: <20230907024710.866917011@goodmis.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-trace-kernel@vger.kernel.org From: "Steven Rostedt (Google)" The option files update the options for a given trace array. For an instance, if the file is opened and the instance is deleted, reading or writing to the file will cause a use after free. Up the ref count of the trace_array when an option file is opened. Link: https://lore.kernel.org/all/1cb3aee2-19af-c472-e265-05176fe9bd84@huawei.com/ Cc: stable@vger.kernel.org Fixes: 8530dec63e7b4 ("tracing: Add tracing_check_open_get_tr()") Signed-off-by: Steven Rostedt (Google) --- kernel/trace/trace.c | 23 ++++++++++++++++++++++- 1 file changed, 22 insertions(+), 1 deletion(-) diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index b82df33d20ff..0608ad20cf30 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -8988,12 +8988,33 @@ trace_options_write(struct file *filp, const char __user *ubuf, size_t cnt, return cnt; } +static int tracing_open_options(struct inode *inode, struct file *filp) +{ + struct trace_option_dentry *topt = inode->i_private; + int ret; + + ret = tracing_check_open_get_tr(topt->tr); + if (ret) + return ret; + + filp->private_data = inode->i_private; + return 0; +} + +static int tracing_release_options(struct inode *inode, struct file *file) +{ + struct trace_option_dentry *topt = file->private_data; + + trace_array_put(topt->tr); + return 0; +} static const struct file_operations trace_options_fops = { - .open = tracing_open_generic, + .open = tracing_open_options, .read = trace_options_read, .write = trace_options_write, .llseek = generic_file_llseek, + .release = tracing_release_options, }; /*