xmlsecurity: check for errors in OCipherContext::Create()

If this function returns null, storing a document will proceed without
reporting an error to the user, and lose all the data.

Change-Id: I0f9fd53702321e7997b28e12eb5bed3349bbcc13
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/160435
Tested-by: Jenkins
Reviewed-by: Michael Stahl <michael.stahl@allotropia.de>

1 files changed, 1 insertions, 0 deletions

diff --git a/xmlsecurity/source/xmlsec/nss/nssinitializer.cxx b/xmlsecurity/source/xmlsec/nss/nssinitializer.cxx
index 69e165c550fc..83a83a9ea551 100644
--- a/xmlsecurity/source/xmlsec/nss/nssinitializer.cxx
+++ b/xmlsecurity/source/xmlsec/nss/nssinitializer.cxx
@@ -606,6 +606,7 @@ css::uno::Reference< css::xml::crypto::XCipherContext > SAL_CALL ONSSInitializer
             throw css::lang::IllegalArgumentException("Unexpected length of initialization vector.", css::uno::Reference< css::uno::XInterface >(), 3 );
 
         xResult = OCipherContext::Create( nNSSCipherID, aKey, aInitializationVector, bEncryption, bW3CPadding );
+        assert(xResult.is());
     }
 
     return xResult;