openssl: avoid NULL pointer dereference in three places

There are three potential NULL pointer dereference in
EVP_DigestInit_ex(), dh_pub_encode() and dsa_pub_encode()
functions.
Fix them by adding proper null pointer check.

[YOCTO #4600]
[ CQID: WIND00373257 ]

(From OE-Core rev: 4779d3c89cf0129763a4f5b7306c1247a0d6d021)

Signed-off-by: Xufeng Zhang <xufeng.zhang@windriver.com>
Signed-off-by: Saul Wold <sgw@linux.intel.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

1 files changed, 21 insertions, 0 deletions

diff --git a/meta/recipes-connectivity/openssl/openssl-1.0.1e/openssl-avoid-NULL-pointer-dereference-in-EVP_DigestInit_ex.patch b/meta/recipes-connectivity/openssl/openssl-1.0.1e/openssl-avoid-NULL-pointer-dereference-in-EVP_DigestInit_ex.patch
new file mode 100644
index 0000000000..c161e62f62
--- /dev/null
+++ b/meta/recipes-connectivity/openssl/openssl-1.0.1e/openssl-avoid-NULL-pointer-dereference-in-EVP_DigestInit_ex.patch
@@ -0,0 +1,21 @@
+openssl: avoid NULL pointer dereference in EVP_DigestInit_ex()
+
+We should avoid accessing the type pointer if it's NULL,
+this could happen if ctx->digest is not NULL.
+
+Upstream-Status: Submitted
+http://www.mail-archive.com/openssl-dev@openssl.org/msg32860.html
+
+Signed-off-by: Xufeng Zhang <xufeng.zhang@windriver.com>
+---
+--- a/crypto/evp/digest.c
++++ b/crypto/evp/digest.c
+@@ -199,7 +199,7 @@
+                return 0;
+                }
+ #endif
+-       if (ctx->digest != type)
++       if (type && (ctx->digest != type))
+                {
+                if (ctx->digest && ctx->digest->ctx_size)
+                        OPENSSL_free(ctx->md_data);