[PATCH] ecryptfs: fix crypto_alloc_blkcipher() error check

The return value of crypto_alloc_blkcipher() should be checked by IS_ERR().

Cc: Mike Halcrow <mhalcrow@us.ibm.com>
Cc: Phillip Hellewell <phillip@hellewell.homeip.net>
Signed-off-by: NAkinobu Mita <akinobu.mita@gmail.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

fs/ecryptfs/crypto.c

@@ -820,7 +820,8 @@ int ecryptfs_init_crypt_ctx(struct ecryptfs_crypt_stat *crypt_stat)
 	crypt_stat->tfm = crypto_alloc_blkcipher(full_alg_name, 0,
 						 CRYPTO_ALG_ASYNC);
 	kfree(full_alg_name);
-	if (!crypt_stat->tfm) {
+	if (IS_ERR(crypt_stat->tfm)) {
+		rc = PTR_ERR(crypt_stat->tfm);
 		ecryptfs_printk(KERN_ERR, "cryptfs: init_crypt_ctx(): "
 				"Error initializing cipher [%s]\n",
 				crypt_stat->cipher);