Fix a possible crash in dsa_builtin_paramgen2.

Reviewed-by: Rich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/3675)
(cherry picked from commit fb0a64126b8c11a6961dfa1323c3602b591af7df)

diff --git a/crypto/dsa/dsa_gen.c b/crypto/dsa/dsa_gen.c
index 1fce0f81c24242476c2b6a41d5e0a4a66f37a82f..21af2e159fb26ad5818102ecdfe1ababcd2636fd 100644 (file)
--- a/crypto/dsa/dsa_gen.c
+++ b/crypto/dsa/dsa_gen.c
@@ -482,6 +482,8 @@ int dsa_builtin_paramgen2(DSA *ret, size_t L, size_t N,
     } else {
         p = BN_CTX_get(ctx);
         q = BN_CTX_get(ctx);
+        if (q == NULL)
+            goto err;
     }
 
     if (!BN_lshift(test, BN_value_one(), L - 1))