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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 2DF53C3527D for ; Mon, 21 Feb 2022 09:58:46 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1353509AbiBUJ5a (ORCPT ); Mon, 21 Feb 2022 04:57:30 -0500 Received: from mxb-00190b01.gslb.pphosted.com ([23.128.96.19]:42232 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1351314AbiBUJss (ORCPT ); Mon, 21 Feb 2022 04:48:48 -0500 Received: from sin.source.kernel.org (sin.source.kernel.org [145.40.73.55]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C013732046; Mon, 21 Feb 2022 01:22:32 -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 sin.source.kernel.org (Postfix) with ESMTPS id AB6C4CE0E8B; Mon, 21 Feb 2022 09:22:30 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 90422C340E9; Mon, 21 Feb 2022 09:22:28 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1645435349; bh=08eY0msXADLduerMwecp2drQdDRqyeIrBiLp/rfWPzA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=kGwe1pok6DOzsV7cSuKJKg6RAPkPk3IfMjXydpYlwZxNSbBp2H39b3xaNSFogokGD Xq3NL2vLP9ECl72Nrb5WIcEzhrO81ycnpnMC8MroQCXUZMPVxIGt3EIlcyiabdDzAe DKv+wQut285bQJRSwPxKjCC3Hr6BQql0lK2abRdw= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Adrian Hunter , Ian Rogers , Jiri Olsa , Namhyung Kim , Wang ShaoBo , Arnaldo Carvalho de Melo Subject: [PATCH 5.16 132/227] perf bpf: Defer freeing string after possible strlen() on it Date: Mon, 21 Feb 2022 09:49:11 +0100 Message-Id: <20220221084939.247694791@linuxfoundation.org> X-Mailer: git-send-email 2.35.1 In-Reply-To: <20220221084934.836145070@linuxfoundation.org> References: <20220221084934.836145070@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Arnaldo Carvalho de Melo commit 31ded1535e3182778a1d0e5c32711f55da3bc512 upstream. This was detected by the gcc in Fedora Rawhide's gcc: 50 11.01 fedora:rawhide : FAIL gcc version 12.0.1 20220205 (Red Hat 12.0.1-0) (GCC) inlined from 'bpf__config_obj' at util/bpf-loader.c:1242:9: util/bpf-loader.c:1225:34: error: pointer 'map_opt' may be used after 'free' [-Werror=use-after-free] 1225 | *key_scan_pos += strlen(map_opt); | ^~~~~~~~~~~~~~~ util/bpf-loader.c:1223:9: note: call to 'free' here 1223 | free(map_name); | ^~~~~~~~~~~~~~ cc1: all warnings being treated as errors So do the calculations on the pointer before freeing it. Fixes: 04f9bf2bac72480c ("perf bpf-loader: Add missing '*' for key_scan_pos") Cc: Adrian Hunter Cc: Ian Rogers Cc: Jiri Olsa Cc: Namhyung Kim Cc: Wang ShaoBo Link: https://lore.kernel.org/lkml/Yg1VtQxKrPpS3uNA@kernel.org Signed-off-by: Arnaldo Carvalho de Melo Signed-off-by: Greg Kroah-Hartman --- tools/perf/util/bpf-loader.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) --- a/tools/perf/util/bpf-loader.c +++ b/tools/perf/util/bpf-loader.c @@ -1214,9 +1214,10 @@ bpf__obj_config_map(struct bpf_object *o pr_debug("ERROR: Invalid map config option '%s'\n", map_opt); err = -BPF_LOADER_ERRNO__OBJCONF_MAP_OPT; out: - free(map_name); if (!err) *key_scan_pos += strlen(map_opt); + + free(map_name); return err; }