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From: arnaldo.melo@gmail.com
Date: Tue, 7 May 2024 00:15:48 -0300
To: Yang Jihong <yangjihong1@huawei.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>,
	Ian Rogers <irogers@google.com>, Jiri Olsa <jolsa@kernel.org>,
	Kan Liang <kan.liang@linux.intel.com>,
	Namhyung Kim <namhyung@kernel.org>,
	Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
	linux-perf-users@vger.kernel.org
Subject: [PATCH 1/1] perf kwork: Use zfree() to avoid possibly accessing
 dangling pointers
Message-ID: <Zjmc5EiN6zmWZj4r@x1>
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When freeing a->b it is good practice to set a->b to NULL using
zfree(&a->b) so that when we have a bug where a reference to a freed 'a'
pointer is kept somewhere, we can more quickly cause a segfault if some
code tries to use a->b.

Convert one such case in the 'perf kwork' codebase.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Yang Jihong <yangjihong1@huawei.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
---
 tools/perf/builtin-kwork.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/tools/perf/builtin-kwork.c b/tools/perf/builtin-kwork.c
index 0092b9b39611d7e9..56e3f3a5e03a2d66 100644
--- a/tools/perf/builtin-kwork.c
+++ b/tools/perf/builtin-kwork.c
@@ -2230,7 +2230,7 @@ static int perf_kwork__top(struct perf_kwork *kwork)
 	perf_kwork__top_report(kwork);
 
 out:
-	free(kwork->top_stat.cpus_runtime);
+	zfree(&kwork->top_stat.cpus_runtime);
 	return ret;
 }
 
-- 
2.44.0