4.18-stable review patch. If anyone has any objections, please let me know.
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From: Jay Kamat jgkamat@fb.com
[ Upstream commit 48c2bb0b9cf863e0ed78e269f188ce65b73e0fd1 ]
Fix a couple issues with cg_read_strcmp(), to improve correctness of cgroup tests - Fix cg_read_strcmp() always returning 0 for empty "needle" strings. Previously, this function read to a size = 1 buffer when comparing against empty strings, which would lead to cg_read_strcmp() comparing two empty strings. - Fix a memory leak in cg_read_strcmp()
Fixes: 84092dbcf901 ("selftests: cgroup: add memory controller self-tests")
Signed-off-by: Jay Kamat jgkamat@fb.com Acked-by: Roman Gushchin guro@fb.com Signed-off-by: Shuah Khan (Samsung OSG) shuah@kernel.org Signed-off-by: Sasha Levin alexander.levin@microsoft.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- tools/testing/selftests/cgroup/cgroup_util.c | 17 ++++++++++++++--- 1 file changed, 14 insertions(+), 3 deletions(-)
--- a/tools/testing/selftests/cgroup/cgroup_util.c +++ b/tools/testing/selftests/cgroup/cgroup_util.c @@ -89,17 +89,28 @@ int cg_read(const char *cgroup, const ch int cg_read_strcmp(const char *cgroup, const char *control, const char *expected) { - size_t size = strlen(expected) + 1; + size_t size; char *buf; + int ret; + + /* Handle the case of comparing against empty string */ + if (!expected) + size = 32; + else + size = strlen(expected) + 1;
buf = malloc(size); if (!buf) return -1;
- if (cg_read(cgroup, control, buf, size)) + if (cg_read(cgroup, control, buf, size)) { + free(buf); return -1; + }
- return strcmp(expected, buf); + ret = strcmp(expected, buf); + free(buf); + return ret; }
int cg_read_strstr(const char *cgroup, const char *control, const char *needle)