1 files changed, 13 insertions, 1 deletions
diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c
index 828518bb947b..56b4b0e08b3b 100644
--- a/kernel/bpf/syscall.c
+++ b/kernel/bpf/syscall.c
@@ -166,13 +166,25 @@ void bpf_map_area_free(void *area)
 	kvfree(area);
 }
 
+static u32 bpf_map_flags_retain_permanent(u32 flags)
+{
+	/* Some map creation flags are not tied to the map object but
+	 * rather to the map fd instead, so they have no meaning upon
+	 * map object inspection since multiple file descriptors with
+	 * different (access) properties can exist here. Thus, given
+	 * this has zero meaning for the map itself, lets clear these
+	 * from here.
+	 */
+	return flags & ~(BPF_F_RDONLY | BPF_F_WRONLY);
+}
+
 void bpf_map_init_from_attr(struct bpf_map *map, union bpf_attr *attr)
 {
 	map->map_type = attr->map_type;
 	map->key_size = attr->key_size;
 	map->value_size = attr->value_size;
 	map->max_entries = attr->max_entries;
-	map->map_flags = attr->map_flags;
+	map->map_flags = bpf_map_flags_retain_permanent(attr->map_flags);
 	map->numa_node = bpf_map_attr_numa_node(attr);
 }