[NetLabel]: Verify sensitivity level has a valid CIPSO mapping

The current CIPSO engine has a problem where it does not verify that
the given sensitivity level has a valid CIPSO mapping when the "std"
CIPSO DOI type is used.  The end result is that bad packets are sent
on the wire which should have never been sent in the first place.
This patch corrects this problem by verifying the sensitivity level
mapping similar to what is done with the category mapping.  This patch
also changes the returned error code in this case to -EPERM to better
match what the category mapping verification code returns.

Signed-off-by: Paul Moore <paul.moore@hp.com>
Acked-by: James Morris <jmorris@namei.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/net/ipv4/cipso_ipv4.c b/net/ipv4/cipso_ipv4.c
index 60aafb4a8adff56c8fa3fd54d664fd76e2ee7177..c976dd7e9758f5e4fbf9f0cfe38c0e68002154c1 100644 (file)
--- a/net/ipv4/cipso_ipv4.c
+++ b/net/ipv4/cipso_ipv4.c
@@ -732,11 +732,12 @@ static int cipso_v4_map_lvl_hton(const struct cipso_v4_doi *doi_def,
                *net_lvl = host_lvl;
                return 0;
        case CIPSO_V4_MAP_STD:
-               if (host_lvl < doi_def->map.std->lvl.local_size) {
+               if (host_lvl < doi_def->map.std->lvl.local_size &&
+                   doi_def->map.std->lvl.local[host_lvl] < CIPSO_V4_INV_LVL) {
                        *net_lvl = doi_def->map.std->lvl.local[host_lvl];
                        return 0;
                }
-               break;
+               return -EPERM;
        }
 
        return -EINVAL;
@@ -771,7 +772,7 @@ static int cipso_v4_map_lvl_ntoh(const struct cipso_v4_doi *doi_def,
                        *host_lvl = doi_def->map.std->lvl.cipso[net_lvl];
                        return 0;
                }
-               break;
+               return -EPERM;
        }
 
        return -EINVAL;