From: Eric Biggers <ebiggers@xxxxxxxxxx>
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@xxxxxxxxxxxxx>
Signed-off-by: Eric Biggers <ebiggers@xxxxxxxxxx>
---
fs/crypto/crypto.c | 15 +++++++++------
1 file changed, 9 insertions(+), 6 deletions(-)
diff --git a/fs/crypto/crypto.c b/fs/crypto/crypto.c
index e6802d7aca3c7..9cda0147fca95 100644
--- a/fs/crypto/crypto.c
+++ b/fs/crypto/crypto.c
@@ -161,7 +161,10 @@ 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);
@@ -224,8 +227,6 @@ 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,
@@ -237,7 +238,8 @@ 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);
@@ -274,8 +276,9 @@ 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);
--
2.21.0.1020.gf2820cf01a-goog
