Make BN_num_bits_word constant-time.

[openssl.git] / crypto / ex_data.c

diff --git a/crypto/ex_data.c b/crypto/ex_data.c
index d947f3edac4bd0dafa46075d1e4e2af113625b4a..723b21b3d28181c09b1fe3410beab5e7e1ebfb0b 100644 (file)
--- a/crypto/ex_data.c
+++ b/crypto/ex_data.c
@@ -459,7 +459,7 @@ static int int_dup_ex_data(int class_index, CRYPTO_EX_DATA *to,
                            CRYPTO_EX_DATA *from)
 {
     int mx, j, i;
-    char *ptr;
+    void *ptr;
     CRYPTO_EX_DATA_FUNCS **storage = NULL;
     EX_CLASS_ITEM *item;
     if (!from->sk)
@@ -473,6 +473,15 @@ static int int_dup_ex_data(int class_index, CRYPTO_EX_DATA *to,
     if (j < mx)
         mx = j;
     if (mx > 0) {
+        /*
+         * Make sure the ex_data stack is at least |mx| elements long to avoid
+         * issues in the for loop that follows; so go get the |mx|'th element
+         * (if it does not exist CRYPTO_get_ex_data() returns NULL), and assign
+         * to itself. This is normally a no-op; but ensures the stack is the
+         * proper size
+         */
+        if (!CRYPTO_set_ex_data(to, mx - 1, CRYPTO_get_ex_data(to, mx - 1)))
+            goto skip;
         storage = OPENSSL_malloc(mx * sizeof(CRYPTO_EX_DATA_FUNCS *));
         if (!storage)
             goto skip;