[PATCH v2 net-next 04/12] bpf: check for reserved flag bits in array and stack maps

[Alexei Starovoitov <ast@fb.com>]

Suggested-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
---
 kernel/bpf/arraymap.c | 2 +-
 kernel/bpf/stackmap.c | 3 +++
 2 files changed, 4 insertions(+), 1 deletion(-)

diff --git a/kernel/bpf/arraymap.c b/kernel/bpf/arraymap.c
index bd3bdf2486a7..76d5a794e426 100644
--- a/kernel/bpf/arraymap.c
+++ b/kernel/bpf/arraymap.c
@@ -53,7 +53,7 @@ static struct bpf_map *array_map_alloc(union bpf_attr *attr)
 
 	/* check sanity of attributes */
 	if (attr->max_entries == 0 || attr->key_size != 4 ||
-	    attr->value_size == 0)
+	    attr->value_size == 0 || attr->map_flags)
 		return ERR_PTR(-EINVAL);
 
 	if (attr->value_size >= 1 << (KMALLOC_SHIFT_MAX - 1))
diff --git a/kernel/bpf/stackmap.c b/kernel/bpf/stackmap.c
index 8a60ee14a977..f0a02c344358 100644
--- a/kernel/bpf/stackmap.c
+++ b/kernel/bpf/stackmap.c
@@ -35,6 +35,9 @@ static struct bpf_map *stack_map_alloc(union bpf_attr *attr)
 	if (!capable(CAP_SYS_ADMIN))
 		return ERR_PTR(-EPERM);
 
+	if (attr->map_flags)
+		return ERR_PTR(-EINVAL);
+
 	/* check sanity of attributes */
 	if (attr->max_entries == 0 || attr->key_size != 4 ||
 	    value_size < 8 || value_size % 8 ||
-- 
2.8.0.rc1