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=-13.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS 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 8097AC433F5 for ; Wed, 8 Sep 2021 19:20:57 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 68A8060F6C for ; Wed, 8 Sep 2021 19:20:57 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1350989AbhIHTV6 (ORCPT ); Wed, 8 Sep 2021 15:21:58 -0400 Received: from mail.kernel.org ([198.145.29.99]:34174 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1350956AbhIHTVf (ORCPT ); Wed, 8 Sep 2021 15:21:35 -0400 Received: from gandalf.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 4E59761175; Wed, 8 Sep 2021 19:20:27 +0000 (UTC) Received: from rostedt by gandalf.local.home with local (Exim 4.94.2) (envelope-from ) id 1mO36v-0014XO-LR; Wed, 08 Sep 2021 15:19:53 -0400 Message-ID: <20210908191953.503827696@goodmis.org> User-Agent: quilt/0.66 Date: Wed, 08 Sep 2021 15:18:53 -0400 From: Steven Rostedt To: linux-kernel@vger.kernel.org Cc: Ingo Molnar , Andrew Morton , Dan Carpenter Subject: [for-next][PATCH 02/12] tracing: Fix some alloc_event_probe() error handling bugs References: <20210908191851.381347939@goodmis.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Dan Carpenter There are two bugs in this code. First, if the kzalloc() fails it leads to a NULL dereference of "ep" on the next line. Second, if the alloc_event_probe() function returns an error then it leads to an error pointer dereference in the caller. Link: https://lkml.kernel.org/r/20210824115150.GI31143@kili Fixes: 7491e2c44278 ("tracing: Add a probe that attaches to trace events") Signed-off-by: Dan Carpenter Signed-off-by: Steven Rostedt (VMware) --- kernel/trace/trace_eprobe.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/kernel/trace/trace_eprobe.c b/kernel/trace/trace_eprobe.c index 56a96e9750cf..3044b762cbd7 100644 --- a/kernel/trace/trace_eprobe.c +++ b/kernel/trace/trace_eprobe.c @@ -151,7 +151,7 @@ static struct trace_eprobe *alloc_event_probe(const char *group, ep = kzalloc(struct_size(ep, tp.args, nargs), GFP_KERNEL); if (!ep) { - trace_event_put_ref(ep->event); + trace_event_put_ref(event); goto error; } ep->event = event; @@ -851,7 +851,8 @@ static int __trace_eprobe_create(int argc, const char *argv[]) ret = PTR_ERR(ep); /* This must return -ENOMEM, else there is a bug */ WARN_ON_ONCE(ret != -ENOMEM); - goto error; /* We know ep is not allocated */ + ep = NULL; + goto error; } argc -= 2; argv += 2; -- 2.32.0