evp: fix improper use of negative value issues

[openssl.git] / crypto / evp / e_aes.c

diff --git a/crypto/evp/e_aes.c b/crypto/evp/e_aes.c
index 2c2a4ba90c141e299a92f5fe4a64031f28d56767..e43076752f3a5dbbf2d468fe4e022def5dd3cbdf 100644 (file)
--- a/crypto/evp/e_aes.c
+++ b/crypto/evp/e_aes.c
@@ -2516,9 +2516,14 @@ static int aes_cfb1_cipher(EVP_CIPHER_CTX *ctx, unsigned char *out,
 static int aes_ctr_cipher(EVP_CIPHER_CTX *ctx, unsigned char *out,
                           const unsigned char *in, size_t len)
 {
-    unsigned int num = EVP_CIPHER_CTX_get_num(ctx);
+    int n = EVP_CIPHER_CTX_get_num(ctx);
+    unsigned int num;
     EVP_AES_KEY *dat = EVP_C_DATA(EVP_AES_KEY,ctx);
 
+    if (n < 0)
+        return 0;
+    num = (unsigned int)n;
+
     if (dat->stream.ctr)
         CRYPTO_ctr128_encrypt_ctr32(in, out, len, &dat->ks,
                                     ctx->iv,