From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 8DBA83F6619; Wed, 20 May 2026 18:16:12 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1779300973; cv=none; b=MgzP8cQst6pA2kHMCGUdeHELjlWYvaHrOmGS71EG9nUVZ3LUTc8d+t+16xzgDZ+zU+3W9vcH1c8+s/7Ly3pdDI5LN8f13DGe3a4P1jQvcqHuUzzHXpfnvKNS6jUbXqSaN7lM58WOnGs2eLSXNQtYmo4uO6hOKPoNHEC0tyM7Xo0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1779300973; c=relaxed/simple; bh=4tufP1NMZrY1F5wmecGBBlAGcTvrN91QCHu+OaabPE8=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=bOJhMOuWcdcnXUTVnbl3pVSBo6OvfLd2Fm6npifwqQwvjJ7Ep8aCYKoXDiYBz0vIge7U36cXSjiBFy2//3bXapSDWckUpetFFQqp8iAYQKBwujMMsUau6BtCxDcvUTFgSCPrg840ORE3QxBQmFgmd1uHXn64R52+CrQu7MdFuW8= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=lsF3INvS; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="lsF3INvS" Received: by smtp.kernel.org (Postfix) with ESMTPSA id F281B1F000E9; Wed, 20 May 2026 18:16:11 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1779300972; bh=3OYDoDZFyv05nHG+VDtx1Y5NHyVwKoc9492QKkLMiYA=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=lsF3INvSa6rtWWHxvqeeH14z6SUpOZ7GNTJjpogr/ex2LHRd5jCeF4aCZtxGmJ12f JVa4Oda0l8WTlDXIX5CP5W7XGBgvpzbEI1E4lfoae5MKIZBbe0od0Ia8GZaVt3iUBE Yr1/Z+GNLrQMigCsBSsNd7vDIZ5LqsbLbguDmGnY= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Ian Rogers , Sun Jian , Namhyung Kim , Sasha Levin Subject: [PATCH 6.12 377/666] perf cgroup: Update metric leader in evlist__expand_cgroup Date: Wed, 20 May 2026 18:19:48 +0200 Message-ID: <20260520162119.421988645@linuxfoundation.org> X-Mailer: git-send-email 2.54.0 In-Reply-To: <20260520162111.222830634@linuxfoundation.org> References: <20260520162111.222830634@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.12-stable review patch. If anyone has any objections, please let me know. ------------------ From: Ian Rogers [ Upstream commit c9ef786c0970991578397043f1c819229e2b7197 ] When the evlist is expanded the metric leader wasn't being updated. As the original evsel is deleted this creates a use-after-free in stat-shadow's prepare_metric. This was detected running the "perf stat --bpf-counters --for-each-cgroup test" with sanitizers. The change itself puts the copied evsel into the priv field (known unused because of evsel__clone use) and then in a second pass over the list updates the copied values using the priv pointer. Fixes: d1c5a0e86a4e ("perf stat: Add --for-each-cgroup option") Signed-off-by: Ian Rogers Acked-by: Sun Jian Signed-off-by: Namhyung Kim Signed-off-by: Sasha Levin --- tools/perf/util/cgroup.c | 30 +++++++++++++++++++++++------- 1 file changed, 23 insertions(+), 7 deletions(-) diff --git a/tools/perf/util/cgroup.c b/tools/perf/util/cgroup.c index fbcc0626f9ce2..e172bcdf7fcb1 100644 --- a/tools/perf/util/cgroup.c +++ b/tools/perf/util/cgroup.c @@ -417,7 +417,6 @@ int evlist__expand_cgroup(struct evlist *evlist, const char *str, struct rblist *metric_events, bool open_cgroup) { struct evlist *orig_list, *tmp_list; - struct evsel *pos, *evsel, *leader; struct rblist orig_metric_events; struct cgroup *cgrp = NULL; struct cgroup_name *cn; @@ -456,6 +455,7 @@ int evlist__expand_cgroup(struct evlist *evlist, const char *str, goto out_err; list_for_each_entry(cn, &cgroup_list, list) { + struct evsel *pos; char *name; if (!cn->used) @@ -471,21 +471,37 @@ int evlist__expand_cgroup(struct evlist *evlist, const char *str, if (cgrp == NULL) continue; - leader = NULL; + /* copy the list and set to the new cgroup. */ evlist__for_each_entry(orig_list, pos) { - evsel = evsel__clone(/*dest=*/NULL, pos); + struct evsel *evsel = evsel__clone(/*dest=*/NULL, pos); + if (evsel == NULL) goto out_err; + /* stash the copy during the copying. */ + pos->priv = evsel; cgroup__put(evsel->cgrp); evsel->cgrp = cgroup__get(cgrp); - if (evsel__is_group_leader(pos)) - leader = evsel; - evsel__set_leader(evsel, leader); - evlist__add(tmp_list, evsel); } + /* update leader information using stashed pointer to copy. */ + evlist__for_each_entry(orig_list, pos) { + struct evsel *evsel = pos->priv; + + if (evsel__leader(pos)) + evsel__set_leader(evsel, evsel__leader(pos)->priv); + + if (pos->metric_leader) + evsel->metric_leader = pos->metric_leader->priv; + + if (pos->first_wildcard_match) + evsel->first_wildcard_match = pos->first_wildcard_match->priv; + } + /* the stashed copy is no longer used. */ + evlist__for_each_entry(orig_list, pos) + pos->priv = NULL; + /* cgroup__new() has a refcount, release it here */ cgroup__put(cgrp); nr_cgroups++; -- 2.53.0