[PATCH] selftests: cgroup: Add 'malloc' failures checks in test_memcontrol

[Ivan Orlov <ivan.orlov0322@gmail.com>]

There are several 'malloc' calls in test_memcontrol, which can be
unsuccessful. This patch will add 'malloc' failures checking to
give more details about test's fail reasons and avoid possible
undefined behavior during the future null dereference (like the
one in alloc_anon_50M_check_swap function).

Signed-off-by: Ivan Orlov <ivan.orlov0322@gmail.com>
---
 tools/testing/selftests/cgroup/test_memcontrol.c | 15 +++++++++++++++
 1 file changed, 15 insertions(+)

diff --git a/tools/testing/selftests/cgroup/test_memcontrol.c b/tools/testing/selftests/cgroup/test_memcontrol.c
index 1e616a8c6a9c..f4f7c0aef702 100644
--- a/tools/testing/selftests/cgroup/test_memcontrol.c
+++ b/tools/testing/selftests/cgroup/test_memcontrol.c
@@ -98,6 +98,11 @@ static int alloc_anon_50M_check(const char *cgroup, void *arg)
 	int ret = -1;
 
 	buf = malloc(size);
+	if (buf == NULL) {
+		fprintf(stderr, "malloc() failed\n");
+		return -1;
+	}
+
 	for (ptr = buf; ptr < buf + size; ptr += PAGE_SIZE)
 		*ptr = 0;
 
@@ -211,6 +216,11 @@ static int alloc_anon_noexit(const char *cgroup, void *arg)
 	char *buf, *ptr;
 
 	buf = malloc(size);
+	if (buf == NULL) {
+		fprintf(stderr, "malloc() failed\n");
+		return -1;
+	}
+
 	for (ptr = buf; ptr < buf + size; ptr += PAGE_SIZE)
 		*ptr = 0;
 
@@ -778,6 +788,11 @@ static int alloc_anon_50M_check_swap(const char *cgroup, void *arg)
 	int ret = -1;
 
 	buf = malloc(size);
+	if (buf == NULL) {
+		fprintf(stderr, "malloc() failed\n");
+		return -1;
+	}
+
 	for (ptr = buf; ptr < buf + size; ptr += PAGE_SIZE)
 		*ptr = 0;
 
-- 
2.34.1