f2fs crypto: check for too-short encrypted file names

This patch adopts:
	ext4 crypto: check for too-short encrypted file names

An encrypted file name should never be shorter than an 16 bytes, the
AES block size.  The 3.10 crypto layer will oops and crash the kernel
if ciphertext shorter than the block size is passed to it.

Fortunately, in modern kernels the crypto layer will not crash the
kernel in this scenario, but nevertheless, it represents a corrupted
directory, and we should detect it and mark the file system as
corrupted so that e2fsck can fix this.

Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
This commit is contained in:
Jaegeuk Kim 2016-02-05 19:37:27 -08:00
parent ce855a3bd0
commit 1dafa51d45
1 changed files with 4 additions and 1 deletions

View File

@ -317,7 +317,10 @@ int f2fs_fname_disk_to_usr(struct inode *inode,
oname->len = iname->len;
return oname->len;
}
if (iname->len < F2FS_CRYPTO_BLOCK_SIZE) {
printk("encrypted inode too small");
return -EUCLEAN;
}
if (F2FS_I(inode)->i_crypt_info)
return f2fs_fname_decrypt(inode, iname, oname);