From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752412AbeCWNXQ (ORCPT ); Fri, 23 Mar 2018 09:23:16 -0400 Received: from mga11.intel.com ([192.55.52.93]:3235 "EHLO mga11.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752289AbeCWNXP (ORCPT ); Fri, 23 Mar 2018 09:23:15 -0400 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.48,350,1517904000"; d="scan'208";a="26937403" Message-ID: <1521811393.27781.2.camel@tzanussi-mobl.amr.corp.intel.com> Subject: Re: [PATCH] tracing: Fix a potential NULL dereference From: Tom Zanussi To: Dan Carpenter Cc: Steven Rostedt , Ingo Molnar , linux-kernel@vger.kernel.org, kernel-janitors@vger.kernel.org Date: Fri, 23 Mar 2018 08:23:13 -0500 In-Reply-To: <20180323113735.GC28518@mwanda> References: <20180323113735.GC28518@mwanda> Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.10.4 (3.10.4-4.fc20) Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Dan, On Fri, 2018-03-23 at 14:37 +0300, Dan Carpenter wrote: > We forgot to set the error code on this path so we return ERR_PTR(0) > which is NULL. It results in a NULL dereference in the caller. > > Fixes: 100719dcef44 ("tracing: Add simple expression support to hist triggers") > Signed-off-by: Dan Carpenter > > diff --git a/kernel/trace/trace_events_hist.c b/kernel/trace/trace_events_hist.c > index 4f027642ceef..a02bc09d765a 100644 > --- a/kernel/trace/trace_events_hist.c > +++ b/kernel/trace/trace_events_hist.c > @@ -2776,6 +2776,7 @@ static struct hist_field *parse_expr(struct hist_trigger_data *hist_data, > expr->fn = hist_field_plus; > break; > default: > + ret = -EINVAL; > goto free; > } > Acked-by: Tom Zanussi Thanks for catching this! Tom