From nobody Sun Sep 14 10:18:17 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 6F41AC54E94 for ; Wed, 25 Jan 2023 16:20:27 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235909AbjAYQU0 (ORCPT ); Wed, 25 Jan 2023 11:20:26 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:52288 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235649AbjAYQUO (ORCPT ); Wed, 25 Jan 2023 11:20:14 -0500 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D1D3756194; Wed, 25 Jan 2023 08:20:12 -0800 (PST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 6741F61465; Wed, 25 Jan 2023 16:20:12 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id D7460C433AC; Wed, 25 Jan 2023 16:20:11 +0000 (UTC) Received: from rostedt by gandalf.local.home with local (Exim 4.96) (envelope-from ) id 1pKiVP-004Mt2-02; Wed, 25 Jan 2023 11:20:11 -0500 Message-ID: <20230125162010.827695718@goodmis.org> User-Agent: quilt/0.66 Date: Wed, 25 Jan 2023 11:18:30 -0500 From: Steven Rostedt To: linux-kernel@vger.kernel.org Cc: Masami Hiramatsu , Andrew Morton , stable@vger.kernel.org, Natalia Petrova Subject: [for-linus][PATCH 06/11] trace_events_hist: add check for return value of create_hist_field References: <20230125161824.332648375@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: Natalia Petrova Function 'create_hist_field' is called recursively at trace_events_hist.c:1954 and can return NULL-value that's why we have to check it to avoid null pointer dereference. Found by Linux Verification Center (linuxtesting.org) with SVACE. Link: https://lkml.kernel.org/r/20230111120409.4111-1-n.petrova@fintech.ru Cc: stable@vger.kernel.org Fixes: 30350d65ac56 ("tracing: Add variable support to hist triggers") Signed-off-by: Natalia Petrova Signed-off-by: Steven Rostedt (Google) --- kernel/trace/trace_events_hist.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/kernel/trace/trace_events_hist.c b/kernel/trace/trace_events_h= ist.c index fcaf226b7744..5edbf6b1da3f 100644 --- a/kernel/trace/trace_events_hist.c +++ b/kernel/trace/trace_events_hist.c @@ -1988,6 +1988,8 @@ static struct hist_field *create_hist_field(struct hi= st_trigger_data *hist_data, hist_field->fn_num =3D flags & HIST_FIELD_FL_LOG2 ? HIST_FIELD_FN_LOG2 : HIST_FIELD_FN_BUCKET; hist_field->operands[0] =3D create_hist_field(hist_data, field, fl, NULL= ); + if (!hist_field->operands[0]) + goto free; hist_field->size =3D hist_field->operands[0]->size; hist_field->type =3D kstrdup_const(hist_field->operands[0]->type, GFP_KE= RNEL); if (!hist_field->type) --=20 2.39.0