selftests/cgroup: Add NULL check after malloc in cgroup_util.c

Add NULL checks after malloc() in three helper functions to prevent
NULL pointer dereference on memory allocation failure.
- cg_name()
- cg_name_indexed()
- cg_control()

These functions allocate memory with malloc() but previously called
snprintf() unconditionally, which would trigger undefined behavior
if allocation fails.

Signed-off-by: Hongfu Li <lihongfu@kylinos.cn>
Signed-off-by: Tejun Heo <tj@kernel.org>

0 files changed, 0 insertions, 0 deletions