If BN_rand() or BN_pseudo_rand() are called with a NULL rnd argument,

BN_bin2bn() will helpfully allocate a BN which is then leaked. Avoid this
by explicitly checking for NULL at the start of the bnrand() function.

Fixes Coverity ID 78831.

ok miod@

2 files changed, 16 insertions, 6 deletions

diff --git a/src/lib/libcrypto/bn/bn_rand.c b/src/lib/libcrypto/bn/bn_rand.c
index 334c65dd57..ac5c5eb308 100644
--- a/src/lib/libcrypto/bn/bn_rand.c
+++ b/src/lib/libcrypto/bn/bn_rand.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: bn_rand.c,v 1.16 2014/10/22 13:02:04 jsing Exp $ */
+/* $OpenBSD: bn_rand.c,v 1.17 2015/02/19 06:10:29 jsing Exp $ */
 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
  * All rights reserved.
  *
@@ -123,9 +123,14 @@ bnrand(int pseudorand, BIGNUM *rnd, int bits, int top, int bottom)
         unsigned char *buf = NULL;
         int ret = 0, bit, bytes, mask;
 
+        if (rnd == NULL) {
+                BNerr(BN_F_BNRAND, ERR_R_PASSED_NULL_PARAMETER);
+                return (0);
+        }
+
         if (bits == 0) {
                 BN_zero(rnd);
-                return 1;
+                return (1);
         }
 
         bytes = (bits + 7) / 8;
@@ -175,7 +180,7 @@ bnrand(int pseudorand, BIGNUM *rnd, int bits, int top, int bottom)
         buf[0] &= ~mask;
         if (bottom) /* set bottom bit if requested */
                 buf[bytes - 1] |= 1;
-        if (!BN_bin2bn(buf, bytes, rnd))
+        if (BN_bin2bn(buf, bytes, rnd) == NULL)
                 goto err;
         ret = 1;
 
diff --git a/src/lib/libssl/src/crypto/bn/bn_rand.c b/src/lib/libssl/src/crypto/bn/bn_rand.c
index 334c65dd57..ac5c5eb308 100644
--- a/src/lib/libssl/src/crypto/bn/bn_rand.c
+++ b/src/lib/libssl/src/crypto/bn/bn_rand.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: bn_rand.c,v 1.16 2014/10/22 13:02:04 jsing Exp $ */
+/* $OpenBSD: bn_rand.c,v 1.17 2015/02/19 06:10:29 jsing Exp $ */
 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
  * All rights reserved.
  *
@@ -123,9 +123,14 @@ bnrand(int pseudorand, BIGNUM *rnd, int bits, int top, int bottom)
         unsigned char *buf = NULL;
         int ret = 0, bit, bytes, mask;
 
+        if (rnd == NULL) {
+                BNerr(BN_F_BNRAND, ERR_R_PASSED_NULL_PARAMETER);
+                return (0);
+        }
+
         if (bits == 0) {
                 BN_zero(rnd);
-                return 1;
+                return (1);
         }
 
         bytes = (bits + 7) / 8;
@@ -175,7 +180,7 @@ bnrand(int pseudorand, BIGNUM *rnd, int bits, int top, int bottom)
         buf[0] &= ~mask;
         if (bottom) /* set bottom bit if requested */
                 buf[bytes - 1] |= 1;
-        if (!BN_bin2bn(buf, bytes, rnd))
+        if (BN_bin2bn(buf, bytes, rnd) == NULL)
                 goto err;
         ret = 1;