selftests/cgroup: check malloc return value in alloc_anon functions

The alloc_anon() function calls malloc() without checking for a NULL
return. If memory allocation fails, a NULL pointer dereference will
occur when accessing the buffer.

Add proper error handling to return -1 when malloc() fails in all
four alloc_anon variants:
- alloc_anon()
- alloc_anon_50M_check()
- alloc_anon_noexit()
- alloc_anon_50M_check_swap()

Signed-off-by: Hongfu Li <lihongfu@kylinos.cn>
Reviewed-by: Vishal Moola <vishal.moola@gmail.com>
Reviewed-by: Muchun Song <muchun.song@linux.dev>
Signed-off-by: Tejun Heo <tj@kernel.org>

0 files changed, 0 insertions, 0 deletions