From patchwork Tue Aug 10 17:30:11 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg Kroah-Hartman X-Patchwork-Id: 495010 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=-19.5 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER, INCLUDES_PATCH, MAILING_LIST_MULTI, SPF_HELO_NONE, SPF_PASS, URIBL_BLOCKED, USER_AGENT_GIT 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 E94AAC432BE for ; Tue, 10 Aug 2021 17:48:36 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D284161250 for ; Tue, 10 Aug 2021 17:48:36 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233567AbhHJRsz (ORCPT ); Tue, 10 Aug 2021 13:48:55 -0400 Received: from mail.kernel.org ([198.145.29.99]:60930 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236222AbhHJRq6 (ORCPT ); Tue, 10 Aug 2021 13:46:58 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 11CFE61205; Tue, 10 Aug 2021 17:40:46 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1628617247; bh=TJODZfoAYA3RjHfN0cW75/6oU4OUeKSGaJcJUgPBnSI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=E9OhdmvZrc9otTBtNi7X1Hsy3PC0QbVweISg7NTX5KeRjZ777lLfoHLrk4bP7h5TD 8YT/ZNZhOeUtgFVZHdFhy0ck791EDGxFadhlH11RAWvUtHLHVPrOWE4r/LAkjKbXIB 4OYyDJYD/Vw+rXeN164E2ksLjdsD1xGrgk8iqArs= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Kamal Agrawal , "Steven Rostedt (VMware)" Subject: [PATCH 5.10 077/135] tracing: Fix NULL pointer dereference in start_creating Date: Tue, 10 Aug 2021 19:30:11 +0200 Message-Id: <20210810172958.348192105@linuxfoundation.org> X-Mailer: git-send-email 2.32.0 In-Reply-To: <20210810172955.660225700@linuxfoundation.org> References: <20210810172955.660225700@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Kamal Agrawal commit ff41c28c4b54052942180d8b3f49e75f1445135a upstream. The event_trace_add_tracer() can fail. In this case, it leads to a crash in start_creating with below call stack. Handle the error scenario properly in trace_array_create_dir. Call trace: down_write+0x7c/0x204 start_creating.25017+0x6c/0x194 tracefs_create_file+0xc4/0x2b4 init_tracer_tracefs+0x5c/0x940 trace_array_create_dir+0x58/0xb4 trace_array_create+0x1bc/0x2b8 trace_array_get_by_name+0xdc/0x18c Link: https://lkml.kernel.org/r/1627651386-21315-1-git-send-email-kamaagra@codeaurora.org Cc: stable@vger.kernel.org Fixes: 4114fbfd02f1 ("tracing: Enable creating new instance early boot") Signed-off-by: Kamal Agrawal Signed-off-by: Steven Rostedt (VMware) Signed-off-by: Greg Kroah-Hartman --- kernel/trace/trace.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -8683,8 +8683,10 @@ static int trace_array_create_dir(struct return -EINVAL; ret = event_trace_add_tracer(tr->dir, tr); - if (ret) + if (ret) { tracefs_remove(tr->dir); + return ret; + } init_tracer_tracefs(tr, tr->dir); __update_tracer_options(tr);