upstream: change explicit_bzero();free() to freezero()

While freezero() returns early if the pointer is NULL the tests for
NULL in callers are left to avoid warnings about passing an
uninitialised size argument across a function boundry.

ok deraadt@ djm@

OpenBSD-Commit-ID: 2660fa334fcc7cd05ec74dd99cb036f9ade6384a

1 files changed, 7 insertions, 13 deletions

diff --git a/ssh-xmss.c b/ssh-xmss.c
index 4c734fd7..ccd4c760 100644
--- a/ssh-xmss.c
+++ b/ssh-xmss.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: ssh-xmss.c,v 1.1 2018/02/23 15:58:38 markus Exp $*/
+/* $OpenBSD: ssh-xmss.c,v 1.2 2020/02/26 13:40:09 jsg Exp $*/
 /*
  * Copyright (c) 2017 Stefan-Lukas Gazdag.
  * Copyright (c) 2017 Markus Friedl.
@@ -103,10 +103,8 @@ ssh_xmss_sign(const struct sshkey *key, u_char **sigp, size_t *lenp,
 		r = ret;
 	}
 	sshbuf_free(b);
-	if (sig != NULL) {
-		explicit_bzero(sig, slen);
-		free(sig);
-	}
+	if (sig != NULL)
+		freezero(sig, slen);
 
 	return r;
 }
@@ -177,14 +175,10 @@ ssh_xmss_verify(const struct sshkey *key,
 	/* success */
 	r = 0;
  out:
-	if (sm != NULL) {
-		explicit_bzero(sm, smlen);
-		free(sm);
-	}
-	if (m != NULL) {
-		explicit_bzero(m, smlen); /* NB mlen may be invalid if r != 0 */
-		free(m);
-	}
+	if (sm != NULL)
+		freezero(sm, smlen);
+	if (m != NULL)
+		freezero(m, smlen);
 	sshbuf_free(b);
 	free(ktype);
 	return r;