upstream: memleak in error path; spotted by oss-fuzz, ok markus@

OpenBSD-Commit-ID: d6ed260cbbc297ab157ad63931802fb1ef7a4266

1 files changed, 17 insertions, 9 deletions

diff --git a/sshkey-xmss.c b/sshkey-xmss.c
index 9e5f5e475..e8e2e3816 100644
--- a/sshkey-xmss.c
+++ b/sshkey-xmss.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: sshkey-xmss.c,v 1.6 2019/10/09 00:02:57 djm Exp $ */
+/* $OpenBSD: sshkey-xmss.c,v 1.7 2019/10/14 06:00:02 djm Exp $ */
 /*
  * Copyright (c) 2017 Markus Friedl.  All rights reserved.
  *
@@ -748,7 +748,7 @@ sshkey_xmss_deserialize_state(struct sshkey *k, struct sshbuf *b)
         u_int32_t i, lh, node;
         size_t ls, lsl, la, lk, ln, lr;
         char *magic;
-        int r;
+        int r = SSH_ERR_INTERNAL_ERROR;
 
         if (state == NULL)
                 return SSH_ERR_INVALID_ARGUMENT;
@@ -767,9 +767,11 @@ sshkey_xmss_deserialize_state(struct sshkey *k, struct sshbuf *b)
             (r = sshbuf_get_string(b, &state->th_nodes, &ln)) != 0 ||
             (r = sshbuf_get_string(b, &state->retain, &lr)) != 0 ||
             (r = sshbuf_get_u32(b, &lh)) != 0)
-                return r;
-        if (strcmp(magic, SSH_XMSS_K2_MAGIC) != 0)
-                return SSH_ERR_INVALID_ARGUMENT;
+                goto out;
+        if (strcmp(magic, SSH_XMSS_K2_MAGIC) != 0) {
+                r = SSH_ERR_INVALID_ARGUMENT;
+                goto out;
+        }
         /* XXX check stackoffset */
         if (ls != num_stack(state) ||
             lsl != num_stacklevels(state) ||
@@ -777,8 +779,10 @@ sshkey_xmss_deserialize_state(struct sshkey *k, struct sshbuf *b)
             lk != num_keep(state) ||
             ln != num_th_nodes(state) ||
             lr != num_retain(state) ||
-            lh != num_treehash(state))
-                return SSH_ERR_INVALID_ARGUMENT;
+            lh != num_treehash(state)) {
+                r = SSH_ERR_INVALID_ARGUMENT;
+                goto out;
+        }
         for (i = 0; i < num_treehash(state); i++) {
                 th = &state->treehash[i];
                 if ((r = sshbuf_get_u32(b, &th->h)) != 0 ||
@@ -786,7 +790,7 @@ sshkey_xmss_deserialize_state(struct sshkey *k, struct sshbuf *b)
                     (r = sshbuf_get_u32(b, &th->stackusage)) != 0 ||
                     (r = sshbuf_get_u8(b, &th->completed)) != 0 ||
                     (r = sshbuf_get_u32(b, &node)) != 0)
-                        return r;
+                        goto out;
                 if (node < num_th_nodes(state))
                         th->node = &state->th_nodes[node];
         }
@@ -794,7 +798,11 @@ sshkey_xmss_deserialize_state(struct sshkey *k, struct sshbuf *b)
         xmss_set_bds_state(&state->bds, state->stack, state->stackoffset,
             state->stacklevels, state->auth, state->keep, state->treehash,
             state->retain, 0);
-        return 0;
+        /* success */
+        r = 0;
+ out:
+        free(magic);
+        return r;
 }
 
 int