f2fs crypto: replace some BUG_ON()'s with error checks

BugLink: http://bugs.launchpad.net/bugs/1729107

commit 66aa3e12 upstream.

This patch adopts:
	ext4 crypto: replace some BUG_ON()'s with error checks
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

fs/f2fs/crypto.c

@@ -362,7 +362,6 @@ static int f2fs_page_crypto(struct f2fs_crypto_ctx *ctx,
 	else
 		res = crypto_ablkcipher_encrypt(req);
 	if (res == -EINPROGRESS || res == -EBUSY) {
-		BUG_ON(req->base.data != &ecr);
 		wait_for_completion(&ecr.completion);
 		res = ecr.res;
 	}

fs/f2fs/crypto_fname.c

@@ -124,7 +124,6 @@ static int f2fs_fname_encrypt(struct inode *inode,
 	ablkcipher_request_set_crypt(req, &src_sg, &dst_sg, ciphertext_len, iv);
 	res = crypto_ablkcipher_encrypt(req);
 	if (res == -EINPROGRESS || res == -EBUSY) {
-		BUG_ON(req->base.data != &ecr);
 		wait_for_completion(&ecr.completion);
 		res = ecr.res;
 	}
@@ -180,7 +179,6 @@ static int f2fs_fname_decrypt(struct inode *inode,
 	ablkcipher_request_set_crypt(req, &src_sg, &dst_sg, iname->len, iv);
 	res = crypto_ablkcipher_decrypt(req);
 	if (res == -EINPROGRESS || res == -EBUSY) {
-		BUG_ON(req->base.data != &ecr);
 		wait_for_completion(&ecr.completion);
 		res = ecr.res;
 	}

fs/f2fs/crypto_key.c

@@ -75,7 +75,6 @@ static int f2fs_derive_key_aes(char deriving_key[F2FS_AES_128_ECB_KEY_SIZE],
 					F2FS_AES_256_XTS_KEY_SIZE, NULL);
 	res = crypto_ablkcipher_encrypt(req);
 	if (res == -EINPROGRESS || res == -EBUSY) {
-		BUG_ON(req->base.data != &ecr);
 		wait_for_completion(&ecr.completion);
 		res = ecr.res;
 	}
@@ -189,7 +188,11 @@ int f2fs_get_encryption_info(struct inode *inode)
 		keyring_key = NULL;
 		goto out;
 	}
-	BUG_ON(keyring_key->type != &key_type_logon);
+	if (keyring_key->type != &key_type_logon) {
+		printk_once(KERN_WARNING "f2fs: key type must be logon\n");
+		res = -ENOKEY;
+		goto out;
+	}
 	ukp = user_key_payload(keyring_key);
 	if (ukp->datalen != sizeof(struct f2fs_encryption_key)) {
 		res = -EINVAL;
@@ -198,7 +201,13 @@ int f2fs_get_encryption_info(struct inode *inode)
 	master_key = (struct f2fs_encryption_key *)ukp->data;
 	BUILD_BUG_ON(F2FS_AES_128_ECB_KEY_SIZE !=
 				F2FS_KEY_DERIVATION_NONCE_SIZE);
-	BUG_ON(master_key->size != F2FS_AES_256_XTS_KEY_SIZE);
+	if (master_key->size != F2FS_AES_256_XTS_KEY_SIZE) {
+		printk_once(KERN_WARNING
+				"f2fs: key size incorrect: %d\n",
+				master_key->size);
+		res = -ENOKEY;
+		goto out;
+	}
 	res = f2fs_derive_key_aes(ctx.nonce, master_key->raw,
 				  raw_key);
 	if (res)