ext4 crypto: replace some BUG_ON()'s with error checks

Buggy (or hostile) userspace should not be able to cause the kernel to
crash.

Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@vger.kernel.org
This commit is contained in:
Theodore Ts'o 2015-10-03 10:49:27 -04:00
parent 3684de8ca2
commit 687c3c36e7
4 changed files with 15 additions and 7 deletions

View File

@ -295,7 +295,6 @@ static int ext4_page_crypto(struct inode *inode,
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;
}

View File

@ -120,7 +120,6 @@ static int ext4_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;
}
@ -182,7 +181,6 @@ static int ext4_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;
}

View File

@ -71,7 +71,6 @@ static int ext4_derive_key_aes(char deriving_key[EXT4_AES_128_ECB_KEY_SIZE],
EXT4_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;
}
@ -208,7 +207,12 @@ retry:
goto out;
}
crypt_info->ci_keyring_key = keyring_key;
BUG_ON(keyring_key->type != &key_type_logon);
if (keyring_key->type != &key_type_logon) {
printk_once(KERN_WARNING
"ext4: key type must be logon\n");
res = -ENOKEY;
goto out;
}
ukp = ((struct user_key_payload *)keyring_key->payload.data);
if (ukp->datalen != sizeof(struct ext4_encryption_key)) {
res = -EINVAL;
@ -217,7 +221,13 @@ retry:
master_key = (struct ext4_encryption_key *)ukp->data;
BUILD_BUG_ON(EXT4_AES_128_ECB_KEY_SIZE !=
EXT4_KEY_DERIVATION_NONCE_SIZE);
BUG_ON(master_key->size != EXT4_AES_256_XTS_KEY_SIZE);
if (master_key->size != EXT4_AES_256_XTS_KEY_SIZE) {
printk_once(KERN_WARNING
"ext4: key size incorrect: %d\n",
master_key->size);
res = -ENOKEY;
goto out;
}
res = ext4_derive_key_aes(ctx.nonce, master_key->raw,
raw_key);
if (res)

View File

@ -150,7 +150,8 @@ int ext4_is_child_context_consistent_with_parent(struct inode *parent,
if ((parent == NULL) || (child == NULL)) {
pr_err("parent %p child %p\n", parent, child);
BUG_ON(1);
WARN_ON(1); /* Should never happen */
return 0;
}
/* no restrictions if the parent directory is not encrypted */
if (!ext4_encrypted_inode(parent))