Use explicit_bzero() instead of memset() on buffers going out of scope.

Also, zero the SHA256 context.

suggested by "eric" in a comment on an opensslrampage.org post
ok miod@ deraadt@

1 files changed, 3 insertions, 2 deletions

diff --git a/src/lib/libcrypto/crypto/getentropy_linux.c b/src/lib/libcrypto/crypto/getentropy_linux.c
index 6947102136..eeaf9a4ef9 100644
--- a/src/lib/libcrypto/crypto/getentropy_linux.c
+++ b/src/lib/libcrypto/crypto/getentropy_linux.c
@@ -1,4 +1,4 @@
-/*      $OpenBSD: getentropy_linux.c,v 1.29 2014/07/21 19:15:56 deraadt Exp $   */
+/*      $OpenBSD: getentropy_linux.c,v 1.30 2014/07/21 20:19:47 guenther Exp $  */
 
 /*
  * Copyright (c) 2014 Theo de Raadt <deraadt@openbsd.org>
@@ -539,7 +539,8 @@ getentropy_fallback(void *buf, size_t len)
                 memcpy((char *)buf + i, results, min(sizeof(results), len - i));
                 i += min(sizeof(results), len - i);
         }
-        memset(results, 0, sizeof results);
+        explicit_bzero(&ctx, sizeof ctx);
+        explicit_bzero(results, sizeof results);
         if (gotdata(buf, len) == 0) {
                 errno = save_errno;
                 return 0;               /* satisfied */