From nobody Fri Dec 19 03:44:07 2025 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 CA076EEB57D for ; Sat, 9 Sep 2023 03:23:57 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232115AbjIIDX7 (ORCPT ); Fri, 8 Sep 2023 23:23:59 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59128 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232915AbjIIDXg (ORCPT ); Fri, 8 Sep 2023 23:23:36 -0400 Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B9D211FE5; Fri, 8 Sep 2023 20:23:32 -0700 (PDT) Received: by smtp.kernel.org (Postfix) with ESMTPSA id E7BA6C43397; Sat, 9 Sep 2023 03:23:30 +0000 (UTC) Received: from rostedt by gandalf with local (Exim 4.96) (envelope-from ) id 1qeoZZ-000Ygb-20; Fri, 08 Sep 2023 23:23:49 -0400 Message-ID: <20230909032349.439567528@goodmis.org> User-Agent: quilt/0.66 Date: Fri, 08 Sep 2023 23:16:22 -0400 From: Steven Rostedt To: linux-kernel@vger.kernel.org Cc: Masami Hiramatsu , Mark Rutland , Andrew Morton , stable@vger.kernel.org, Zheng Yejian , Linux Kernel Functional Testing , Naresh Kamboju Subject: [for-linus][PATCH 07/15] tracing: Have option files inc the trace array ref count References: <20230909031615.047488015@goodmis.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" 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://lkml.kernel.org/r/20230907024804.086679464@goodmis.org Link: https://lore.kernel.org/all/1cb3aee2-19af-c472-e265-05176fe9bd84@huaw= ei.com/ Cc: stable@vger.kernel.org Cc: Masami Hiramatsu Cc: Mark Rutland Cc: Andrew Morton Cc: Zheng Yejian Fixes: 8530dec63e7b4 ("tracing: Add tracing_check_open_get_tr()") Tested-by: Linux Kernel Functional Testing Tested-by: Naresh Kamboju 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; } =20 +static int tracing_open_options(struct inode *inode, struct file *filp) +{ + struct trace_option_dentry *topt =3D inode->i_private; + int ret; + + ret =3D tracing_check_open_get_tr(topt->tr); + if (ret) + return ret; + + filp->private_data =3D inode->i_private; + return 0; +} + +static int tracing_release_options(struct inode *inode, struct file *file) +{ + struct trace_option_dentry *topt =3D file->private_data; + + trace_array_put(topt->tr); + return 0; +} =20 static const struct file_operations trace_options_fops =3D { - .open =3D tracing_open_generic, + .open =3D tracing_open_options, .read =3D trace_options_read, .write =3D trace_options_write, .llseek =3D generic_file_llseek, + .release =3D tracing_release_options, }; =20 /* --=20 2.40.1