fscrypt: clean up some BUG_ON()s in block encryption/decryption

Replace some BUG_ON()s with WARN_ON_ONCE() and returning an error code,
and move the check for len divisible by FS_CRYPTO_BLOCK_SIZE into
fscrypt_crypt_block() so that it's done for both encryption and
decryption, not just encryption.

Reviewed-by: Chandan Rajendra <chandan@linux.ibm.com>
Signed-off-by: Eric Biggers <ebiggers@google.com>
This commit is contained in:
Eric Biggers 2019-05-20 09:29:42 -07:00
parent f47fcbb2b5
commit eeacfdc68a

View File

@ -162,7 +162,10 @@ int fscrypt_crypt_block(const struct inode *inode, fscrypt_direction_t rw,
struct crypto_skcipher *tfm = ci->ci_ctfm;
int res = 0;
BUG_ON(len == 0);
if (WARN_ON_ONCE(len <= 0))
return -EINVAL;
if (WARN_ON_ONCE(len % FS_CRYPTO_BLOCK_SIZE != 0))
return -EINVAL;
fscrypt_generate_iv(&iv, lblk_num, ci);
@ -225,8 +228,6 @@ struct page *fscrypt_encrypt_page(const struct inode *inode,
struct page *ciphertext_page = page;
int err;
BUG_ON(len % FS_CRYPTO_BLOCK_SIZE != 0);
if (inode->i_sb->s_cop->flags & FS_CFLG_OWN_PAGES) {
/* with inplace-encryption we just encrypt the page */
err = fscrypt_crypt_block(inode, FS_ENCRYPT, lblk_num, page,
@ -238,7 +239,8 @@ struct page *fscrypt_encrypt_page(const struct inode *inode,
return ciphertext_page;
}
BUG_ON(!PageLocked(page));
if (WARN_ON_ONCE(!PageLocked(page)))
return ERR_PTR(-EINVAL);
/* The encryption operation will require a bounce page. */
ciphertext_page = fscrypt_alloc_bounce_page(gfp_flags);
@ -275,8 +277,9 @@ EXPORT_SYMBOL(fscrypt_encrypt_page);
int fscrypt_decrypt_page(const struct inode *inode, struct page *page,
unsigned int len, unsigned int offs, u64 lblk_num)
{
if (!(inode->i_sb->s_cop->flags & FS_CFLG_OWN_PAGES))
BUG_ON(!PageLocked(page));
if (WARN_ON_ONCE(!PageLocked(page) &&
!(inode->i_sb->s_cop->flags & FS_CFLG_OWN_PAGES)))
return -EINVAL;
return fscrypt_crypt_block(inode, FS_DECRYPT, lblk_num, page, page,
len, offs, GFP_NOFS);