From: Arnaldo Carvalho de Melo <acme@redhat.com>
Date: Wed, 12 Apr 2023 12:50:08 +0000 (-0300)
Subject: perf c2c: Use zfree() to reduce chances of use after free
X-Git-Tag: v6.4-rc1~1^2~99
X-Git-Url: https://git.kernel.dk/?a=commitdiff_plain;h=190de75481439205f3a9362bd0511fd48ad1a718;p=linux-2.6-block.git

perf c2c: Use zfree() to reduce chances of use after free

Do defensive programming by using zfree() to initialize freed pointers
to NULL, so that eventual use after free result in a NULL pointer deref
instead of more subtle behaviour.

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
---

diff --git a/tools/perf/builtin-c2c.c b/tools/perf/builtin-c2c.c
index 6c12f0865860..08455e26b606 100644
--- a/tools/perf/builtin-c2c.c
+++ b/tools/perf/builtin-c2c.c
@@ -165,8 +165,8 @@ static void *c2c_he_zalloc(size_t size)
 	return &c2c_he->he;
 
 out_free:
-	free(c2c_he->nodeset);
-	free(c2c_he->cpuset);
+	zfree(&c2c_he->nodeset);
+	zfree(&c2c_he->cpuset);
 	free(c2c_he);
 	return NULL;
 }
@@ -178,13 +178,13 @@ static void c2c_he_free(void *he)
 	c2c_he = container_of(he, struct c2c_hist_entry, he);
 	if (c2c_he->hists) {
 		hists__delete_entries(&c2c_he->hists->hists);
-		free(c2c_he->hists);
+		zfree(&c2c_he->hists);
 	}
 
-	free(c2c_he->cpuset);
-	free(c2c_he->nodeset);
-	free(c2c_he->nodestr);
-	free(c2c_he->node_stats);
+	zfree(&c2c_he->cpuset);
+	zfree(&c2c_he->nodeset);
+	zfree(&c2c_he->nodestr);
+	zfree(&c2c_he->node_stats);
 	free(c2c_he);
 }