upstream commit

fix three bugs in KRL code related to (unused) signature
 support: verification length was being incorrectly calculated, multiple
 signatures were being incorrectly processed and a NULL dereference that
 occurred when signatures were verified. Reported by Carl Jackson

Upstream-ID: e705e97ad3ccce84291eaa651708dd1b9692576b

1 files changed, 3 insertions, 4 deletions

diff --git a/krl.c b/krl.c
index ec3b82bea..fff1a3f7c 100644
--- a/krl.c
+++ b/krl.c
@@ -14,7 +14,7 @@
  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  */
 
-/* $OpenBSD: krl.c,v 1.36 2015/12/11 04:21:12 mmcc Exp $ */
+/* $OpenBSD: krl.c,v 1.37 2015/12/31 00:33:52 djm Exp $ */
 
 #include "includes.h"
 
@@ -1015,7 +1015,7 @@ ssh_krl_from_blob(struct sshbuf *buf, struct ssh_krl **krlp,
                 }
                 /* Check signature over entire KRL up to this point */
                 if ((r = sshkey_verify(key, blob, blen,
-                    sshbuf_ptr(buf), sshbuf_len(buf) - sig_off, 0)) != 0)
+                    sshbuf_ptr(buf), sig_off, 0)) != 0)
                         goto out;
                 /* Check if this key has already signed this KRL */
                 for (i = 0; i < nca_used; i++) {
@@ -1036,7 +1036,6 @@ ssh_krl_from_blob(struct sshbuf *buf, struct ssh_krl **krlp,
                 ca_used = tmp_ca_used;
                 ca_used[nca_used++] = key;
                 key = NULL;
-                break;
         }
 
         if (sshbuf_len(copy) != 0) {
@@ -1101,7 +1100,7 @@ ssh_krl_from_blob(struct sshbuf *buf, struct ssh_krl **krlp,
                         r = SSH_ERR_INVALID_FORMAT;
                         goto out;
                 }
-                if (sshbuf_len(sect) > 0) {
+                if (sect != NULL && sshbuf_len(sect) > 0) {
                         error("KRL section contains unparsed data");
                         r = SSH_ERR_INVALID_FORMAT;
                         goto out;