Merge branch 'apw' (xfrm_user fixes)

Merge xfrm_user validation fixes from Andy Whitcroft:
 "Two patches we are applying to Ubuntu for XFRM_MSG_NEWAE validation
  issue reported by ZDI.

  The first of these is the primary fix, and the second is for a more
  theoretical issue that Kees pointed out when reviewing the first"

* emailed patches from Andy Whitcroft <apw@canonical.com>:
  xfrm_user: validate XFRM_MSG_NEWAE incoming ESN size harder
  xfrm_user: validate XFRM_MSG_NEWAE XFRMA_REPLAY_ESN_VAL replay_window

1 files changed, 8 insertions, 1 deletions

diff --git a/net/xfrm/xfrm_user.c b/net/xfrm/xfrm_user.c
index 9705c279494b..40a8aa39220d 100644
--- a/net/xfrm/xfrm_user.c
+++ b/net/xfrm/xfrm_user.c
@@ -412,7 +412,14 @@ static inline int xfrm_replay_verify_len(struct xfrm_replay_state_esn *replay_es
         up = nla_data(rp);
         ulen = xfrm_replay_state_esn_len(up);
 
-        if (nla_len(rp) < ulen || xfrm_replay_state_esn_len(replay_esn) != ulen)
+        /* Check the overall length and the internal bitmap length to avoid
+         * potential overflow. */
+        if (nla_len(rp) < ulen ||
+            xfrm_replay_state_esn_len(replay_esn) != ulen ||
+            replay_esn->bmp_len != up->bmp_len)
+                return -EINVAL;
+
+        if (up->replay_window > up->bmp_len * sizeof(__u32) * 8)
                 return -EINVAL;
 
         return 0;