Fix another possible crash in rsa_ossl_mod_exp.

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

diff --git a/crypto/rsa/rsa_ossl.c b/crypto/rsa/rsa_ossl.c
index 5e0ad92cb1c3c4257f1fd21da0bfad4107d399e5..92c4be1868a5b1608c1ab7841281014c1a51a692 100644 (file)
--- a/crypto/rsa/rsa_ossl.c
+++ b/crypto/rsa/rsa_ossl.c
@@ -608,6 +608,8 @@ static int rsa_ossl_mod_exp(BIGNUM *r0, const BIGNUM *I, RSA *rsa, BN_CTX *ctx)
     r1 = BN_CTX_get(ctx);
     m1 = BN_CTX_get(ctx);
     vrfy = BN_CTX_get(ctx);
+    if (vrfy == NULL)
+        goto err;
 
     {
         BIGNUM *p = BN_new(), *q = BN_new();