Add static check in BN_hex2bn

Fixes #17298

Reviewed-by: Tomas Mraz <tomas@openssl.org>
Reviewed-by: Paul Dale <pauli@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/17299)

diff --git a/crypto/bn/bn_conv.c b/crypto/bn/bn_conv.c
index 6757f3d0aae98c4c5f82a70a7b8963beae85ad6e..75054f5d6a6c7432773276b077dc498e65b9ed64 100644 (file)
--- a/crypto/bn/bn_conv.c
+++ b/crypto/bn/bn_conv.c
@@ -154,6 +154,10 @@ int BN_hex2bn(BIGNUM **bn, const char *a)
             return 0;
     } else {
         ret = *bn;
+        if (BN_get_flags(ret, BN_FLG_STATIC_DATA)) {
+            ERR_raise(ERR_LIB_BN, ERR_R_PASSED_INVALID_ARGUMENT);
+            return 0;
+        }
         BN_zero(ret);
     }