[PATCH -next] libbpf: Add additional null-pointer checking in make_parent_dir

[Gaosheng Cui]

The make_parent_dir is called without null-pointer checking for path,
such as bpf_link__pin. To ensure there is no null-pointer dereference
in make_parent_dir, so make_parent_dir requires additional null-pointer
checking for path.

Signed-off-by: Gaosheng Cui <cuigaosheng1@xxxxxxxxxx>
---
 tools/lib/bpf/libbpf.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c
index b53e51884f9e..5786e6184bf5 100644
--- a/tools/lib/bpf/libbpf.c
+++ b/tools/lib/bpf/libbpf.c
@@ -7634,6 +7634,9 @@ static int make_parent_dir(const char *path)
 	char *dname, *dir;
 	int err = 0;
 
+	if (path == NULL)
+		return -EINVAL;
+
 	dname = strdup(path);
 	if (dname == NULL)
 		return -ENOMEM;
-- 
2.25.1