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-rw-r--r--fs/ext4/crypto.c9
-rw-r--r--fs/ext4/crypto_fname.c284
-rw-r--r--fs/ext4/crypto_key.c74
-rw-r--r--fs/ext4/crypto_policy.c76
-rw-r--r--fs/ext4/dir.c21
-rw-r--r--fs/ext4/ext4.h44
-rw-r--r--fs/ext4/ext4_crypto.h16
-rw-r--r--fs/ext4/file.c4
-rw-r--r--fs/ext4/namei.c42
-rw-r--r--fs/ext4/super.c7
-rw-r--r--fs/ext4/symlink.c15
11 files changed, 246 insertions, 346 deletions
diff --git a/fs/ext4/crypto.c b/fs/ext4/crypto.c
index 918200ed9bf8..3a25aa4f3d94 100644
--- a/fs/ext4/crypto.c
+++ b/fs/ext4/crypto.c
@@ -118,8 +118,9 @@ struct ext4_crypto_ctx *ext4_get_crypto_ctx(struct inode *inode)
struct ext4_crypto_ctx *ctx = NULL;
int res = 0;
unsigned long flags;
- struct ext4_crypt_info *ci = &EXT4_I(inode)->i_crypt_info;
+ struct ext4_crypt_info *ci = EXT4_I(inode)->i_crypt_info;
+ BUG_ON(ci == NULL);
if (!ext4_read_workqueue)
ext4_init_crypto();
@@ -322,7 +323,7 @@ static int ext4_page_crypto(struct ext4_crypto_ctx *ctx,
int res = 0;
BUG_ON(!ctx->tfm);
- BUG_ON(ctx->mode != ei->i_crypt_info.ci_mode);
+ BUG_ON(ctx->mode != ei->i_crypt_info->ci_mode);
if (ctx->mode != EXT4_ENCRYPTION_MODE_AES_256_XTS) {
printk_ratelimited(KERN_ERR
@@ -334,8 +335,8 @@ static int ext4_page_crypto(struct ext4_crypto_ctx *ctx,
crypto_ablkcipher_clear_flags(atfm, ~0);
crypto_tfm_set_flags(ctx->tfm, CRYPTO_TFM_REQ_WEAK_KEY);
- res = crypto_ablkcipher_setkey(atfm, ei->i_crypt_info.ci_raw,
- ei->i_crypt_info.ci_size);
+ res = crypto_ablkcipher_setkey(atfm, ei->i_crypt_info->ci_raw,
+ ei->i_crypt_info->ci_size);
if (res) {
printk_ratelimited(KERN_ERR
"%s: crypto_ablkcipher_setkey() failed\n",
diff --git a/fs/ext4/crypto_fname.c b/fs/ext4/crypto_fname.c
index d9f08ddbfda2..374d0e790315 100644
--- a/fs/ext4/crypto_fname.c
+++ b/fs/ext4/crypto_fname.c
@@ -48,6 +48,12 @@ bool ext4_valid_filenames_enc_mode(uint32_t mode)
return (mode == EXT4_ENCRYPTION_MODE_AES_256_CTS);
}
+static unsigned max_name_len(struct inode *inode)
+{
+ return S_ISLNK(inode->i_mode) ? inode->i_sb->s_blocksize :
+ EXT4_NAME_LEN;
+}
+
/**
* ext4_fname_encrypt() -
*
@@ -55,28 +61,30 @@ bool ext4_valid_filenames_enc_mode(uint32_t mode)
* ciphertext. Errors are returned as negative numbers. We trust the caller to
* allocate sufficient memory to oname string.
*/
-static int ext4_fname_encrypt(struct ext4_fname_crypto_ctx *ctx,
+static int ext4_fname_encrypt(struct inode *inode,
const struct qstr *iname,
struct ext4_str *oname)
{
u32 ciphertext_len;
struct ablkcipher_request *req = NULL;
DECLARE_EXT4_COMPLETION_RESULT(ecr);
- struct crypto_ablkcipher *tfm = ctx->ctfm;
+ struct ext4_crypt_info *ci = EXT4_I(inode)->i_crypt_info;
+ struct crypto_ablkcipher *tfm = ci->ci_ctfm;
int res = 0;
char iv[EXT4_CRYPTO_BLOCK_SIZE];
struct scatterlist src_sg, dst_sg;
- int padding = 4 << (ctx->flags & EXT4_POLICY_FLAGS_PAD_MASK);
+ int padding = 4 << (ci->ci_flags & EXT4_POLICY_FLAGS_PAD_MASK);
char *workbuf, buf[32], *alloc_buf = NULL;
+ unsigned lim = max_name_len(inode);
- if (iname->len <= 0 || iname->len > ctx->lim)
+ if (iname->len <= 0 || iname->len > lim)
return -EIO;
ciphertext_len = (iname->len < EXT4_CRYPTO_BLOCK_SIZE) ?
EXT4_CRYPTO_BLOCK_SIZE : iname->len;
ciphertext_len = ext4_fname_crypto_round_up(ciphertext_len, padding);
- ciphertext_len = (ciphertext_len > ctx->lim)
- ? ctx->lim : ciphertext_len;
+ ciphertext_len = (ciphertext_len > lim)
+ ? lim : ciphertext_len;
if (ciphertext_len <= sizeof(buf)) {
workbuf = buf;
@@ -134,7 +142,7 @@ static int ext4_fname_encrypt(struct ext4_fname_crypto_ctx *ctx,
* Errors are returned as negative numbers.
* We trust the caller to allocate sufficient memory to oname string.
*/
-static int ext4_fname_decrypt(struct ext4_fname_crypto_ctx *ctx,
+static int ext4_fname_decrypt(struct inode *inode,
const struct ext4_str *iname,
struct ext4_str *oname)
{
@@ -142,11 +150,13 @@ static int ext4_fname_decrypt(struct ext4_fname_crypto_ctx *ctx,
struct ablkcipher_request *req = NULL;
DECLARE_EXT4_COMPLETION_RESULT(ecr);
struct scatterlist src_sg, dst_sg;
- struct crypto_ablkcipher *tfm = ctx->ctfm;
+ struct ext4_crypt_info *ci = EXT4_I(inode)->i_crypt_info;
+ struct crypto_ablkcipher *tfm = ci->ci_ctfm;
int res = 0;
char iv[EXT4_CRYPTO_BLOCK_SIZE];
+ unsigned lim = max_name_len(inode);
- if (iname->len <= 0 || iname->len > ctx->lim)
+ if (iname->len <= 0 || iname->len > lim)
return -EIO;
tmp_in[0].name = iname->name;
@@ -242,171 +252,50 @@ static int digest_decode(const char *src, int len, char *dst)
return cp - dst;
}
-/**
- * ext4_free_fname_crypto_ctx() -
- *
- * Frees up a crypto context.
- */
-void ext4_free_fname_crypto_ctx(struct ext4_fname_crypto_ctx *ctx)
-{
- if (ctx == NULL || IS_ERR(ctx))
- return;
-
- if (ctx->ctfm && !IS_ERR(ctx->ctfm))
- crypto_free_ablkcipher(ctx->ctfm);
- if (ctx->htfm && !IS_ERR(ctx->htfm))
- crypto_free_hash(ctx->htfm);
- kfree(ctx);
-}
-
-/**
- * ext4_put_fname_crypto_ctx() -
- *
- * Return: The crypto context onto free list. If the free list is above a
- * threshold, completely frees up the context, and returns the memory.
- *
- * TODO: Currently we directly free the crypto context. Eventually we should
- * add code it to return to free list. Such an approach will increase
- * efficiency of directory lookup.
- */
-void ext4_put_fname_crypto_ctx(struct ext4_fname_crypto_ctx **ctx)
+int ext4_setup_fname_crypto(struct inode *inode)
{
- if (*ctx == NULL || IS_ERR(*ctx))
- return;
- ext4_free_fname_crypto_ctx(*ctx);
- *ctx = NULL;
-}
-
-/**
- * ext4_alloc_fname_crypto_ctx() -
- */
-struct ext4_fname_crypto_ctx *ext4_alloc_fname_crypto_ctx(
- const struct ext4_crypt_info *ci)
-{
- struct ext4_fname_crypto_ctx *ctx;
-
- ctx = kmalloc(sizeof(struct ext4_fname_crypto_ctx), GFP_NOFS);
- if (ctx == NULL)
- return ERR_PTR(-ENOMEM);
- if (ci->ci_mode == EXT4_ENCRYPTION_MODE_INVALID) {
- /* This will automatically set key mode to invalid
- * As enum for ENCRYPTION_MODE_INVALID is zero */
- memset(&ctx->ci, 0, sizeof(ctx->ci));
- } else {
- memcpy(&ctx->ci, ci, sizeof(struct ext4_crypt_info));
- }
- ctx->has_valid_key = (EXT4_ENCRYPTION_MODE_INVALID == ci->ci_mode)
- ? 0 : 1;
- ctx->ctfm_key_is_ready = 0;
- ctx->ctfm = NULL;
- ctx->htfm = NULL;
- return ctx;
-}
-
-/**
- * ext4_get_fname_crypto_ctx() -
- *
- * Allocates a free crypto context and initializes it to hold
- * the crypto material for the inode.
- *
- * Return: NULL if not encrypted. Error value on error. Valid pointer otherwise.
- */
-struct ext4_fname_crypto_ctx *ext4_get_fname_crypto_ctx(
- struct inode *inode, u32 max_ciphertext_len)
-{
- struct ext4_fname_crypto_ctx *ctx;
struct ext4_inode_info *ei = EXT4_I(inode);
+ struct ext4_crypt_info *ci = ei->i_crypt_info;
+ struct crypto_ablkcipher *ctfm;
int res;
/* Check if the crypto policy is set on the inode */
res = ext4_encrypted_inode(inode);
if (res == 0)
- return NULL;
-
- if (!ext4_has_encryption_key(inode))
- ext4_generate_encryption_key(inode);
-
- /* Get a crypto context based on the key. */
- ctx = ext4_alloc_fname_crypto_ctx(&(ei->i_crypt_info));
- if (IS_ERR(ctx))
- return ctx;
-
- ctx->flags = ei->i_crypt_policy_flags;
- if (ctx->has_valid_key) {
- if (ctx->ci.ci_mode != EXT4_ENCRYPTION_MODE_AES_256_CTS) {
- printk_once(KERN_WARNING
- "ext4: unsupported key mode %d\n",
- ctx->ci.ci_mode);
- return ERR_PTR(-ENOKEY);
- }
+ return 0;
- /* As a first cut, we will allocate new tfm in every call.
- * later, we will keep the tfm around, in case the key gets
- * re-used */
- if (ctx->ctfm == NULL) {
- ctx->ctfm = crypto_alloc_ablkcipher("cts(cbc(aes))",
- 0, 0);
- }
- if (IS_ERR(ctx->ctfm)) {
- res = PTR_ERR(ctx->ctfm);
- printk(
- KERN_DEBUG "%s: error (%d) allocating crypto tfm\n",
- __func__, res);
- ctx->ctfm = NULL;
- ext4_put_fname_crypto_ctx(&ctx);
- return ERR_PTR(res);
- }
- if (ctx->ctfm == NULL) {
- printk(
- KERN_DEBUG "%s: could not allocate crypto tfm\n",
- __func__);
- ext4_put_fname_crypto_ctx(&ctx);
- return ERR_PTR(-ENOMEM);
- }
- ctx->lim = max_ciphertext_len;
- crypto_ablkcipher_clear_flags(ctx->ctfm, ~0);
- crypto_tfm_set_flags(crypto_ablkcipher_tfm(ctx->ctfm),
- CRYPTO_TFM_REQ_WEAK_KEY);
-
- /* If we are lucky, we will get a context that is already
- * set up with the right key. Else, we will have to
- * set the key */
- if (!ctx->ctfm_key_is_ready) {
- /* Since our crypto objectives for filename encryption
- * are pretty weak,
- * we directly use the inode master key */
- res = crypto_ablkcipher_setkey(ctx->ctfm,
- ctx->ci.ci_raw, ctx->ci.ci_size);
- if (res) {
- ext4_put_fname_crypto_ctx(&ctx);
- return ERR_PTR(-EIO);
- }
- ctx->ctfm_key_is_ready = 1;
- } else {
- /* In the current implementation, key should never be
- * marked "ready" for a context that has just been
- * allocated. So we should never reach here */
- BUG();
- }
- }
- if (ctx->htfm == NULL)
- ctx->htfm = crypto_alloc_hash("sha256", 0, CRYPTO_ALG_ASYNC);
- if (IS_ERR(ctx->htfm)) {
- res = PTR_ERR(ctx->htfm);
- printk(KERN_DEBUG "%s: error (%d) allocating hash tfm\n",
- __func__, res);
- ctx->htfm = NULL;
- ext4_put_fname_crypto_ctx(&ctx);
- return ERR_PTR(res);
+ res = ext4_get_encryption_info(inode);
+ if (res < 0)
+ return res;
+ ci = ei->i_crypt_info;
+
+ if (!ci || ci->ci_ctfm)
+ return 0;
+
+ if (ci->ci_mode != EXT4_ENCRYPTION_MODE_AES_256_CTS) {
+ printk_once(KERN_WARNING "ext4: unsupported key mode %d\n",
+ ci->ci_mode);
+ return -ENOKEY;
}
- if (ctx->htfm == NULL) {
- printk(KERN_DEBUG "%s: could not allocate hash tfm\n",
- __func__);
- ext4_put_fname_crypto_ctx(&ctx);
- return ERR_PTR(-ENOMEM);
+
+ ctfm = crypto_alloc_ablkcipher("cts(cbc(aes))", 0, 0);
+ if (!ctfm || IS_ERR(ctfm)) {
+ res = ctfm ? PTR_ERR(ctfm) : -ENOMEM;
+ printk(KERN_DEBUG "%s: error (%d) allocating crypto tfm\n",
+ __func__, res);
+ return res;
}
+ crypto_ablkcipher_clear_flags(ctfm, ~0);
+ crypto_tfm_set_flags(crypto_ablkcipher_tfm(ctfm),
+ CRYPTO_TFM_REQ_WEAK_KEY);
- return ctx;
+ res = crypto_ablkcipher_setkey(ctfm, ci->ci_raw, ci->ci_size);
+ if (res) {
+ crypto_free_ablkcipher(ctfm);
+ return -EIO;
+ }
+ ci->ci_ctfm = ctfm;
+ return 0;
}
/**
@@ -420,40 +309,20 @@ u32 ext4_fname_crypto_round_up(u32 size, u32 blksize)
}
/**
- * ext4_fname_crypto_namelen_on_disk() -
- */
-int ext4_fname_crypto_namelen_on_disk(struct ext4_fname_crypto_ctx *ctx,
- u32 namelen)
-{
- u32 ciphertext_len;
- int padding = 4 << (ctx->flags & EXT4_POLICY_FLAGS_PAD_MASK);
-
- if (ctx == NULL)
- return -EIO;
- if (!(ctx->has_valid_key))
- return -EACCES;
- ciphertext_len = (namelen < EXT4_CRYPTO_BLOCK_SIZE) ?
- EXT4_CRYPTO_BLOCK_SIZE : namelen;
- ciphertext_len = ext4_fname_crypto_round_up(ciphertext_len, padding);
- ciphertext_len = (ciphertext_len > ctx->lim)
- ? ctx->lim : ciphertext_len;
- return (int) ciphertext_len;
-}
-
-/**
* ext4_fname_crypto_alloc_obuff() -
*
* Allocates an output buffer that is sufficient for the crypto operation
* specified by the context and the direction.
*/
-int ext4_fname_crypto_alloc_buffer(struct ext4_fname_crypto_ctx *ctx,
+int ext4_fname_crypto_alloc_buffer(struct inode *inode,
u32 ilen, struct ext4_str *crypto_str)
{
unsigned int olen;
- int padding = 4 << (ctx->flags & EXT4_POLICY_FLAGS_PAD_MASK);
+ int padding = 16;
+ struct ext4_crypt_info *ci = EXT4_I(inode)->i_crypt_info;
- if (!ctx)
- return -EIO;
+ if (ci)
+ padding = 4 << (ci->ci_flags & EXT4_POLICY_FLAGS_PAD_MASK);
if (padding < EXT4_CRYPTO_BLOCK_SIZE)
padding = EXT4_CRYPTO_BLOCK_SIZE;
olen = ext4_fname_crypto_round_up(ilen, padding);
@@ -484,7 +353,7 @@ void ext4_fname_crypto_free_buffer(struct ext4_str *crypto_str)
/**
* ext4_fname_disk_to_usr() - converts a filename from disk space to user space
*/
-int _ext4_fname_disk_to_usr(struct ext4_fname_crypto_ctx *ctx,
+int _ext4_fname_disk_to_usr(struct inode *inode,
struct dx_hash_info *hinfo,
const struct ext4_str *iname,
struct ext4_str *oname)
@@ -492,8 +361,6 @@ int _ext4_fname_disk_to_usr(struct ext4_fname_crypto_ctx *ctx,
char buf[24];
int ret;
- if (ctx == NULL)
- return -EIO;
if (iname->len < 3) {
/*Check for . and .. */
if (iname->name[0] == '.' && iname->name[iname->len-1] == '.') {
@@ -503,8 +370,8 @@ int _ext4_fname_disk_to_usr(struct ext4_fname_crypto_ctx *ctx,
return oname->len;
}
}
- if (ctx->has_valid_key)
- return ext4_fname_decrypt(ctx, iname, oname);
+ if (EXT4_I(inode)->i_crypt_info)
+ return ext4_fname_decrypt(inode, iname, oname);
if (iname->len <= EXT4_FNAME_CRYPTO_DIGEST_SIZE) {
ret = digest_encode(iname->name, iname->len, oname->name);
@@ -523,7 +390,7 @@ int _ext4_fname_disk_to_usr(struct ext4_fname_crypto_ctx *ctx,
return ret + 1;
}
-int ext4_fname_disk_to_usr(struct ext4_fname_crypto_ctx *ctx,
+int ext4_fname_disk_to_usr(struct inode *inode,
struct dx_hash_info *hinfo,
const struct ext4_dir_entry_2 *de,
struct ext4_str *oname)
@@ -531,21 +398,20 @@ int ext4_fname_disk_to_usr(struct ext4_fname_crypto_ctx *ctx,
struct ext4_str iname = {.name = (unsigned char *) de->name,
.len = de->name_len };
- return _ext4_fname_disk_to_usr(ctx, hinfo, &iname, oname);
+ return _ext4_fname_disk_to_usr(inode, hinfo, &iname, oname);
}
/**
* ext4_fname_usr_to_disk() - converts a filename from user space to disk space
*/
-int ext4_fname_usr_to_disk(struct ext4_fname_crypto_ctx *ctx,
+int ext4_fname_usr_to_disk(struct inode *inode,
const struct qstr *iname,
struct ext4_str *oname)
{
int res;
+ struct ext4_crypt_info *ci = EXT4_I(inode)->i_crypt_info;
- if (ctx == NULL)
- return -EIO;
if (iname->len < 3) {
/*Check for . and .. */
if (iname->name[0] == '.' &&
@@ -556,8 +422,8 @@ int ext4_fname_usr_to_disk(struct ext4_fname_crypto_ctx *ctx,
return oname->len;
}
}
- if (ctx->has_valid_key) {
- res = ext4_fname_encrypt(ctx, iname, oname);
+ if (ci) {
+ res = ext4_fname_encrypt(inode, iname, oname);
return res;
}
/* Without a proper key, a user is not allowed to modify the filenames
@@ -569,16 +435,13 @@ int ext4_fname_usr_to_disk(struct ext4_fname_crypto_ctx *ctx,
int ext4_fname_setup_filename(struct inode *dir, const struct qstr *iname,
int lookup, struct ext4_filename *fname)
{
- struct ext4_fname_crypto_ctx *ctx;
+ struct ext4_crypt_info *ci;
int ret = 0, bigname = 0;
memset(fname, 0, sizeof(struct ext4_filename));
fname->usr_fname = iname;
- ctx = ext4_get_fname_crypto_ctx(dir, EXT4_NAME_LEN);
- if (IS_ERR(ctx))
- return PTR_ERR(ctx);
- if ((ctx == NULL) ||
+ if (!ext4_encrypted_inode(dir) ||
((iname->name[0] == '.') &&
((iname->len == 1) ||
((iname->name[1] == '.') && (iname->len == 2))))) {
@@ -586,12 +449,16 @@ int ext4_fname_setup_filename(struct inode *dir, const struct qstr *iname,
fname->disk_name.len = iname->len;
goto out;
}
- if (ctx->has_valid_key) {
- ret = ext4_fname_crypto_alloc_buffer(ctx, iname->len,
+ ret = ext4_setup_fname_crypto(dir);
+ if (ret)
+ return ret;
+ ci = EXT4_I(dir)->i_crypt_info;
+ if (ci) {
+ ret = ext4_fname_crypto_alloc_buffer(dir, iname->len,
&fname->crypto_buf);
if (ret < 0)
goto out;
- ret = ext4_fname_encrypt(ctx, iname, &fname->crypto_buf);
+ ret = ext4_fname_encrypt(dir, iname, &fname->crypto_buf);
if (ret < 0)
goto out;
fname->disk_name.name = fname->crypto_buf.name;
@@ -634,7 +501,6 @@ int ext4_fname_setup_filename(struct inode *dir, const struct qstr *iname,
}
ret = 0;
out:
- ext4_put_fname_crypto_ctx(&ctx);
return ret;
}
diff --git a/fs/ext4/crypto_key.c b/fs/ext4/crypto_key.c
index ec6635dc50f9..0075e43ffea6 100644
--- a/fs/ext4/crypto_key.c
+++ b/fs/ext4/crypto_key.c
@@ -84,14 +84,26 @@ out:
return res;
}
-/**
- * ext4_generate_encryption_key() - generates an encryption key
- * @inode: The inode to generate the encryption key for.
- */
-int ext4_generate_encryption_key(struct inode *inode)
+void ext4_free_encryption_info(struct inode *inode)
+{
+ struct ext4_inode_info *ei = EXT4_I(inode);
+ struct ext4_crypt_info *ci = ei->i_crypt_info;
+
+ if (!ci)
+ return;
+
+ if (ci->ci_keyring_key)
+ key_put(ci->ci_keyring_key);
+ crypto_free_ablkcipher(ci->ci_ctfm);
+ memzero_explicit(&ci->ci_raw, sizeof(ci->ci_raw));
+ kfree(ci);
+ ei->i_crypt_info = NULL;
+}
+
+int _ext4_get_encryption_info(struct inode *inode)
{
struct ext4_inode_info *ei = EXT4_I(inode);
- struct ext4_crypt_info *crypt_info = &ei->i_crypt_info;
+ struct ext4_crypt_info *crypt_info;
char full_key_descriptor[EXT4_KEY_DESC_PREFIX_SIZE +
(EXT4_KEY_DESCRIPTOR_SIZE * 2) + 1];
struct key *keyring_key = NULL;
@@ -99,18 +111,40 @@ int ext4_generate_encryption_key(struct inode *inode)
struct ext4_encryption_context ctx;
struct user_key_payload *ukp;
struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
- int res = ext4_xattr_get(inode, EXT4_XATTR_INDEX_ENCRYPTION,
- EXT4_XATTR_NAME_ENCRYPTION_CONTEXT,
- &ctx, sizeof(ctx));
+ int res;
- if (res != sizeof(ctx)) {
- if (res > 0)
- res = -EINVAL;
- goto out;
+ if (ei->i_crypt_info) {
+ if (!ei->i_crypt_info->ci_keyring_key ||
+ key_validate(ei->i_crypt_info->ci_keyring_key) == 0)
+ return 0;
+ ext4_free_encryption_info(inode);
}
+
+ res = ext4_xattr_get(inode, EXT4_XATTR_INDEX_ENCRYPTION,
+ EXT4_XATTR_NAME_ENCRYPTION_CONTEXT,
+ &ctx, sizeof(ctx));
+ if (res < 0) {
+ if (!DUMMY_ENCRYPTION_ENABLED(sbi))
+ return res;
+ ctx.contents_encryption_mode = EXT4_ENCRYPTION_MODE_AES_256_XTS;
+ ctx.filenames_encryption_mode =
+ EXT4_ENCRYPTION_MODE_AES_256_CTS;
+ ctx.flags = 0;
+ } else if (res != sizeof(ctx))
+ return -EINVAL;
res = 0;
+ crypt_info = kmalloc(sizeof(struct ext4_crypt_info), GFP_KERNEL);
+ if (!crypt_info)
+ return -ENOMEM;
+
ei->i_crypt_policy_flags = ctx.flags;
+ crypt_info->ci_flags = ctx.flags;
+ crypt_info->ci_data_mode = ctx.contents_encryption_mode;
+ crypt_info->ci_filename_mode = ctx.filenames_encryption_mode;
+ crypt_info->ci_ctfm = NULL;
+ memcpy(crypt_info->ci_master_key, ctx.master_key_descriptor,
+ sizeof(crypt_info->ci_master_key));
if (S_ISREG(inode->i_mode))
crypt_info->ci_mode = ctx.contents_encryption_mode;
else if (S_ISDIR(inode->i_mode) || S_ISLNK(inode->i_mode))
@@ -151,17 +185,23 @@ int ext4_generate_encryption_key(struct inode *inode)
res = ext4_derive_key_aes(ctx.nonce, master_key->raw,
crypt_info->ci_raw);
out:
+ if (res < 0) {
+ if (res == -ENOKEY)
+ res = 0;
+ kfree(crypt_info);
+ } else {
+ ei->i_crypt_info = crypt_info;
+ crypt_info->ci_keyring_key = keyring_key;
+ keyring_key = NULL;
+ }
if (keyring_key)
key_put(keyring_key);
- if (res < 0)
- crypt_info->ci_mode = EXT4_ENCRYPTION_MODE_INVALID;
return res;
}
int ext4_has_encryption_key(struct inode *inode)
{
struct ext4_inode_info *ei = EXT4_I(inode);
- struct ext4_crypt_info *crypt_info = &ei->i_crypt_info;
- return (crypt_info->ci_mode != EXT4_ENCRYPTION_MODE_INVALID);
+ return (ei->i_crypt_info != NULL);
}
diff --git a/fs/ext4/crypto_policy.c b/fs/ext4/crypto_policy.c
index a6d6291aea16..370d3aa0a9cf 100644
--- a/fs/ext4/crypto_policy.c
+++ b/fs/ext4/crypto_policy.c
@@ -126,7 +126,7 @@ int ext4_get_policy(struct inode *inode, struct ext4_encryption_policy *policy)
int ext4_is_child_context_consistent_with_parent(struct inode *parent,
struct inode *child)
{
- struct ext4_encryption_context parent_ctx, child_ctx;
+ struct ext4_crypt_info *parent_ci, *child_ci;
int res;
if ((parent == NULL) || (child == NULL)) {
@@ -136,26 +136,28 @@ int ext4_is_child_context_consistent_with_parent(struct inode *parent,
/* no restrictions if the parent directory is not encrypted */
if (!ext4_encrypted_inode(parent))
return 1;
- res = ext4_xattr_get(parent, EXT4_XATTR_INDEX_ENCRYPTION,
- EXT4_XATTR_NAME_ENCRYPTION_CONTEXT,
- &parent_ctx, sizeof(parent_ctx));
- if (res != sizeof(parent_ctx))
- return 0;
/* if the child directory is not encrypted, this is always a problem */
if (!ext4_encrypted_inode(child))
return 0;
- res = ext4_xattr_get(child, EXT4_XATTR_INDEX_ENCRYPTION,
- EXT4_XATTR_NAME_ENCRYPTION_CONTEXT,
- &child_ctx, sizeof(child_ctx));
- if (res != sizeof(child_ctx))
+ res = ext4_get_encryption_info(parent);
+ if (res)
+ return 0;
+ res = ext4_get_encryption_info(child);
+ if (res)
+ return 0;
+ parent_ci = EXT4_I(parent)->i_crypt_info;
+ child_ci = EXT4_I(child)->i_crypt_info;
+ if (!parent_ci && !child_ci)
+ return 1;
+ if (!parent_ci || !child_ci)
return 0;
- return (memcmp(parent_ctx.master_key_descriptor,
- child_ctx.master_key_descriptor,
+
+ return (memcmp(parent_ci->ci_master_key,
+ child_ci->ci_master_key,
EXT4_KEY_DESCRIPTOR_SIZE) == 0 &&
- (parent_ctx.contents_encryption_mode ==
- child_ctx.contents_encryption_mode) &&
- (parent_ctx.filenames_encryption_mode ==
- child_ctx.filenames_encryption_mode));
+ (parent_ci->ci_data_mode == child_ci->ci_data_mode) &&
+ (parent_ci->ci_filename_mode == child_ci->ci_filename_mode) &&
+ (parent_ci->ci_flags == child_ci->ci_flags));
}
/**
@@ -168,31 +170,37 @@ int ext4_is_child_context_consistent_with_parent(struct inode *parent,
int ext4_inherit_context(struct inode *parent, struct inode *child)
{
struct ext4_encryption_context ctx;
- int res = ext4_xattr_get(parent, EXT4_XATTR_INDEX_ENCRYPTION,
- EXT4_XATTR_NAME_ENCRYPTION_CONTEXT,
- &ctx, sizeof(ctx));
+ struct ext4_crypt_info *ci;
+ int res;
+
+ res = ext4_get_encryption_info(parent);
+ if (res < 0)
+ return res;
+ ci = EXT4_I(parent)->i_crypt_info;
+ BUG_ON(ci == NULL);
- if (res != sizeof(ctx)) {
- if (DUMMY_ENCRYPTION_ENABLED(EXT4_SB(parent->i_sb))) {
- ctx.format = EXT4_ENCRYPTION_CONTEXT_FORMAT_V1;
- ctx.contents_encryption_mode =
- EXT4_ENCRYPTION_MODE_AES_256_XTS;
- ctx.filenames_encryption_mode =
- EXT4_ENCRYPTION_MODE_AES_256_CTS;
- ctx.flags = 0;
- memset(ctx.master_key_descriptor, 0x42,
- EXT4_KEY_DESCRIPTOR_SIZE);
- res = 0;
- } else {
- goto out;
- }
+ ctx.format = EXT4_ENCRYPTION_CONTEXT_FORMAT_V1;
+ if (DUMMY_ENCRYPTION_ENABLED(EXT4_SB(parent->i_sb))) {
+ ctx.contents_encryption_mode = EXT4_ENCRYPTION_MODE_AES_256_XTS;
+ ctx.filenames_encryption_mode =
+ EXT4_ENCRYPTION_MODE_AES_256_CTS;
+ ctx.flags = 0;
+ memset(ctx.master_key_descriptor, 0x42,
+ EXT4_KEY_DESCRIPTOR_SIZE);
+ res = 0;
+ } else {
+ ctx.contents_encryption_mode = ci->ci_data_mode;
+ ctx.filenames_encryption_mode = ci->ci_filename_mode;
+ ctx.flags = ci->ci_flags;
+ memcpy(ctx.master_key_descriptor, ci->ci_master_key,
+ EXT4_KEY_DESCRIPTOR_SIZE);
}
get_random_bytes(ctx.nonce, EXT4_KEY_DERIVATION_NONCE_SIZE);
res = ext4_xattr_set(child, EXT4_XATTR_INDEX_ENCRYPTION,
EXT4_XATTR_NAME_ENCRYPTION_CONTEXT, &ctx,
sizeof(ctx), 0);
-out:
if (!res)
ext4_set_inode_flag(child, EXT4_INODE_ENCRYPT);
return res;
+
}
diff --git a/fs/ext4/dir.c b/fs/ext4/dir.c
index d799d5d571e9..28cb94fbb1c9 100644
--- a/fs/ext4/dir.c
+++ b/fs/ext4/dir.c
@@ -110,7 +110,6 @@ static int ext4_readdir(struct file *file, struct dir_context *ctx)
struct super_block *sb = inode->i_sb;
struct buffer_head *bh = NULL;
int dir_has_error = 0;
- struct ext4_fname_crypto_ctx *enc_ctx = NULL;
struct ext4_str fname_crypto_str = {.name = NULL, .len = 0};
if (is_dx_dir(inode)) {
@@ -134,16 +133,14 @@ static int ext4_readdir(struct file *file, struct dir_context *ctx)
return err;
}
- enc_ctx = ext4_get_fname_crypto_ctx(inode, EXT4_NAME_LEN);
- if (IS_ERR(enc_ctx))
- return PTR_ERR(enc_ctx);
- if (enc_ctx) {
- err = ext4_fname_crypto_alloc_buffer(enc_ctx, EXT4_NAME_LEN,
+ err = ext4_setup_fname_crypto(inode);
+ if (err)
+ return err;
+ if (ext4_encrypted_inode(inode)) {
+ err = ext4_fname_crypto_alloc_buffer(inode, EXT4_NAME_LEN,
&fname_crypto_str);
- if (err < 0) {
- ext4_put_fname_crypto_ctx(&enc_ctx);
+ if (err < 0)
return err;
- }
}
offset = ctx->pos & (sb->s_blocksize - 1);
@@ -239,8 +236,7 @@ static int ext4_readdir(struct file *file, struct dir_context *ctx)
offset += ext4_rec_len_from_disk(de->rec_len,
sb->s_blocksize);
if (le32_to_cpu(de->inode)) {
- if (enc_ctx == NULL) {
- /* Directory is not encrypted */
+ if (!ext4_encrypted_inode(inode)) {
if (!dir_emit(ctx, de->name,
de->name_len,
le32_to_cpu(de->inode),
@@ -250,7 +246,7 @@ static int ext4_readdir(struct file *file, struct dir_context *ctx)
int save_len = fname_crypto_str.len;
/* Directory is encrypted */
- err = ext4_fname_disk_to_usr(enc_ctx,
+ err = ext4_fname_disk_to_usr(inode,
NULL, de, &fname_crypto_str);
fname_crypto_str.len = save_len;
if (err < 0)
@@ -275,7 +271,6 @@ done:
err = 0;
errout:
#ifdef CONFIG_EXT4_FS_ENCRYPTION
- ext4_put_fname_crypto_ctx(&enc_ctx);
ext4_fname_crypto_free_buffer(&fname_crypto_str);
#endif
brelse(bh);
diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h
index 3cf3bcb6b239..cac1968e63cb 100644
--- a/fs/ext4/ext4.h
+++ b/fs/ext4/ext4.h
@@ -955,7 +955,7 @@ struct ext4_inode_info {
#ifdef CONFIG_EXT4_FS_ENCRYPTION
/* Encryption params */
- struct ext4_crypt_info i_crypt_info;
+ struct ext4_crypt_info *i_crypt_info;
#endif
};
@@ -2096,37 +2096,30 @@ static inline int ext4_sb_has_crypto(struct super_block *sb)
/* crypto_fname.c */
bool ext4_valid_filenames_enc_mode(uint32_t mode);
u32 ext4_fname_crypto_round_up(u32 size, u32 blksize);
-int ext4_fname_crypto_alloc_buffer(struct ext4_fname_crypto_ctx *ctx,
+int ext4_fname_crypto_alloc_buffer(struct inode *inode,
u32 ilen, struct ext4_str *crypto_str);
-int _ext4_fname_disk_to_usr(struct ext4_fname_crypto_ctx *ctx,
+int _ext4_fname_disk_to_usr(struct inode *inode,
struct dx_hash_info *hinfo,
const struct ext4_str *iname,
struct ext4_str *oname);
-int ext4_fname_disk_to_usr(struct ext4_fname_crypto_ctx *ctx,
+int ext4_fname_disk_to_usr(struct inode *inode,
struct dx_hash_info *hinfo,
const struct ext4_dir_entry_2 *de,
struct ext4_str *oname);
-int ext4_fname_usr_to_disk(struct ext4_fname_crypto_ctx *ctx,
+int ext4_fname_usr_to_disk(struct inode *inode,
const struct qstr *iname,
struct ext4_str *oname);
-int ext4_fname_crypto_namelen_on_disk(struct ext4_fname_crypto_ctx *ctx,
- u32 namelen);
#ifdef CONFIG_EXT4_FS_ENCRYPTION
-void ext4_put_fname_crypto_ctx(struct ext4_fname_crypto_ctx **ctx);
-struct ext4_fname_crypto_ctx *ext4_get_fname_crypto_ctx(struct inode *inode,
- u32 max_len);
+int ext4_setup_fname_crypto(struct inode *inode);
void ext4_fname_crypto_free_buffer(struct ext4_str *crypto_str);
int ext4_fname_setup_filename(struct inode *dir, const struct qstr *iname,
int lookup, struct ext4_filename *fname);
void ext4_fname_free_filename(struct ext4_filename *fname);
#else
static inline
-void ext4_put_fname_crypto_ctx(struct ext4_fname_crypto_ctx **ctx) { }
-static inline
-struct ext4_fname_crypto_ctx *ext4_get_fname_crypto_ctx(struct inode *inode,
- u32 max_len)
+int ext4_setup_fname_crypto(struct inode *inode)
{
- return NULL;
+ return 0;
}
static inline void ext4_fname_crypto_free_buffer(struct ext4_str *p) { }
static inline int ext4_fname_setup_filename(struct inode *dir,
@@ -2143,15 +2136,34 @@ static inline void ext4_fname_free_filename(struct ext4_filename *fname) { }
/* crypto_key.c */
-int ext4_generate_encryption_key(struct inode *inode);
+void ext4_free_encryption_info(struct inode *inode);
+int _ext4_get_encryption_info(struct inode *inode);
#ifdef CONFIG_EXT4_FS_ENCRYPTION
int ext4_has_encryption_key(struct inode *inode);
+
+static inline int ext4_get_encryption_info(struct inode *inode)
+{
+ struct ext4_crypt_info *ci = EXT4_I(inode)->i_crypt_info;
+
+ if (!ci ||
+ (ci->ci_keyring_key &&
+ (ci->ci_keyring_key->flags & ((1 << KEY_FLAG_INVALIDATED) |
+ (1 << KEY_FLAG_REVOKED) |
+ (1 << KEY_FLAG_DEAD)))))
+ return _ext4_get_encryption_info(inode);
+ return 0;
+}
+
#else
static inline int ext4_has_encryption_key(struct inode *inode)
{
return 0;
}
+static inline int ext4_get_encryption_info(struct inode *inode)
+{
+ return 0;
+}
#endif
diff --git a/fs/ext4/ext4_crypto.h b/fs/ext4/ext4_crypto.h
index deecbe8968d1..d29687c232bd 100644
--- a/fs/ext4/ext4_crypto.h
+++ b/fs/ext4/ext4_crypto.h
@@ -76,7 +76,13 @@ struct ext4_encryption_key {
struct ext4_crypt_info {
unsigned char ci_mode;
unsigned char ci_size;
+ char ci_data_mode;
+ char ci_filename_mode;
+ char ci_flags;
+ struct crypto_ablkcipher *ci_ctfm;
+ struct key *ci_keyring_key;
char ci_raw[EXT4_MAX_KEY_SIZE];
+ char ci_master_key[EXT4_KEY_DESCRIPTOR_SIZE];
};
#define EXT4_CTX_REQUIRES_FREE_ENCRYPT_FL 0x00000001
@@ -128,16 +134,6 @@ struct ext4_str {
u32 len;
};
-struct ext4_fname_crypto_ctx {
- u32 lim;
- struct crypto_ablkcipher *ctfm;
- struct crypto_hash *htfm;
- struct ext4_crypt_info ci;
- unsigned flags : 8;
- unsigned has_valid_key : 1;
- unsigned ctfm_key_is_ready : 1;
-};
-
/**
* For encrypted symlinks, the ciphertext length is stored at the beginning
* of the string in little-endian format.
diff --git a/fs/ext4/file.c b/fs/ext4/file.c
index 0613c256c344..875ca6b95a4b 100644
--- a/fs/ext4/file.c
+++ b/fs/ext4/file.c
@@ -223,7 +223,7 @@ static int ext4_file_mmap(struct file *file, struct vm_area_struct *vma)
struct inode *inode = file->f_mapping->host;
if (ext4_encrypted_inode(inode)) {
- int err = ext4_generate_encryption_key(inode);
+ int err = ext4_get_encryption_info(inode);
if (err)
return 0;
}
@@ -289,7 +289,7 @@ static int ext4_file_open(struct inode * inode, struct file * filp)
}
ret = dquot_file_open(inode, filp);
if (!ret && ext4_encrypted_inode(inode)) {
- ret = ext4_generate_encryption_key(inode);
+ ret = ext4_get_encryption_info(inode);
if (ret)
ret = -EACCES;
}
diff --git a/fs/ext4/namei.c b/fs/ext4/namei.c
index b3406434c267..9bed99fdd81a 100644
--- a/fs/ext4/namei.c
+++ b/fs/ext4/namei.c
@@ -607,17 +607,14 @@ static struct stats dx_show_leaf(struct inode *dir,
char *name;
struct ext4_str fname_crypto_str
= {.name = NULL, .len = 0};
- struct ext4_fname_crypto_ctx *ctx = NULL;
int res;
name = de->name;
len = de->name_len;
- ctx = ext4_get_fname_crypto_ctx(dir,
- EXT4_NAME_LEN);
- if (IS_ERR(ctx)) {
- printk(KERN_WARNING "Error acquiring"
- " crypto ctxt--skipping crypto\n");
- ctx = NULL;
+ res = ext4_setup_fname_crypto(dir);
+ if (res) {
+ printk(KERN_WARNING "Error setting up"
+ " fname crypto: %d\n", res);
}
if (ctx == NULL) {
/* Directory is not encrypted */
@@ -637,7 +634,6 @@ static struct stats dx_show_leaf(struct inode *dir,
"allocating crypto "
"buffer--skipping "
"crypto\n");
- ext4_put_fname_crypto_ctx(&ctx);
ctx = NULL;
}
res = ext4_fname_disk_to_usr(ctx, NULL, de,
@@ -658,7 +654,6 @@ static struct stats dx_show_leaf(struct inode *dir,
printk("%*.s:(E)%x.%u ", len, name,
h.hash, (unsigned) ((char *) de
- base));
- ext4_put_fname_crypto_ctx(&ctx);
ext4_fname_crypto_free_buffer(
&fname_crypto_str);
}
@@ -944,7 +939,6 @@ static int htree_dirblock_to_tree(struct file *dir_file,
struct buffer_head *bh;
struct ext4_dir_entry_2 *de, *top;
int err = 0, count = 0;
- struct ext4_fname_crypto_ctx *ctx = NULL;
struct ext4_str fname_crypto_str = {.name = NULL, .len = 0}, tmp_str;
dxtrace(printk(KERN_INFO "In htree dirblock_to_tree: block %lu\n",
@@ -959,17 +953,15 @@ static int htree_dirblock_to_tree(struct file *dir_file,
EXT4_DIR_REC_LEN(0));
#ifdef CONFIG_EXT4_FS_ENCRYPTION
/* Check if the directory is encrypted */
- ctx = ext4_get_fname_crypto_ctx(dir, EXT4_NAME_LEN);
- if (IS_ERR(ctx)) {
- err = PTR_ERR(ctx);
+ err = ext4_setup_fname_crypto(dir);
+ if (err) {
brelse(bh);
return err;
}
- if (ctx != NULL) {
- err = ext4_fname_crypto_alloc_buffer(ctx, EXT4_NAME_LEN,
+ if (ext4_encrypted_inode(dir)) {
+ err = ext4_fname_crypto_alloc_buffer(dir, EXT4_NAME_LEN,
&fname_crypto_str);
if (err < 0) {
- ext4_put_fname_crypto_ctx(&ctx);
brelse(bh);
return err;
}
@@ -990,8 +982,7 @@ static int htree_dirblock_to_tree(struct file *dir_file,
continue;
if (de->inode == 0)
continue;
- if (ctx == NULL) {
- /* Directory is not encrypted */
+ if (!ext4_encrypted_inode(dir)) {
tmp_str.name = de->name;
tmp_str.len = de->name_len;
err = ext4_htree_store_dirent(dir_file,
@@ -1001,7 +992,7 @@ static int htree_dirblock_to_tree(struct file *dir_file,
int save_len = fname_crypto_str.len;
/* Directory is encrypted */
- err = ext4_fname_disk_to_usr(ctx, hinfo, de,
+ err = ext4_fname_disk_to_usr(dir, hinfo, de,
&fname_crypto_str);
if (err < 0) {
count = err;
@@ -1021,7 +1012,6 @@ static int htree_dirblock_to_tree(struct file *dir_file,
errout:
brelse(bh);
#ifdef CONFIG_EXT4_FS_ENCRYPTION
- ext4_put_fname_crypto_ctx(&ctx);
ext4_fname_crypto_free_buffer(&fname_crypto_str);
#endif
return count;
@@ -3107,7 +3097,6 @@ static int ext4_symlink(struct inode *dir,
}
if (encryption_required) {
- struct ext4_fname_crypto_ctx *ctx = NULL;
struct qstr istr;
struct ext4_str ostr;
@@ -3119,19 +3108,14 @@ static int ext4_symlink(struct inode *dir,
err = ext4_inherit_context(dir, inode);
if (err)
goto err_drop_inode;
- ctx = ext4_get_fname_crypto_ctx(inode,
- inode->i_sb->s_blocksize);
- if (IS_ERR_OR_NULL(ctx)) {
- /* We just set the policy, so ctx should not be NULL */
- err = (ctx == NULL) ? -EIO : PTR_ERR(ctx);
+ err = ext4_setup_fname_crypto(inode);
+ if (err)
goto err_drop_inode;
- }
istr.name = (const unsigned char *) symname;
istr.len = len;
ostr.name = sd->encrypted_path;
ostr.len = disk_link.len;
- err = ext4_fname_usr_to_disk(ctx, &istr, &ostr);
- ext4_put_fname_crypto_ctx(&ctx);
+ err = ext4_fname_usr_to_disk(inode, &istr, &ostr);
if (err < 0)
goto err_drop_inode;
sd->len = cpu_to_le16(ostr.len);
diff --git a/fs/ext4/super.c b/fs/ext4/super.c
index bcd7a4bc9036..e0dac100fbe6 100644
--- a/fs/ext4/super.c
+++ b/fs/ext4/super.c
@@ -879,9 +879,8 @@ static struct inode *ext4_alloc_inode(struct super_block *sb)
atomic_set(&ei->i_unwritten, 0);
INIT_WORK(&ei->i_rsv_conversion_work, ext4_end_io_rsv_work);
#ifdef CONFIG_EXT4_FS_ENCRYPTION
- ei->i_crypt_info.ci_mode = EXT4_ENCRYPTION_MODE_INVALID;
+ ei->i_crypt_info = NULL;
#endif
-
return &ei->vfs_inode;
}
@@ -958,6 +957,10 @@ void ext4_clear_inode(struct inode *inode)
jbd2_free_inode(EXT4_I(inode)->jinode);
EXT4_I(inode)->jinode = NULL;
}
+#ifdef CONFIG_EXT4_FS_ENCRYPTION
+ if (EXT4_I(inode)->i_crypt_info)
+ ext4_free_encryption_info(inode);
+#endif
}
static struct inode *ext4_nfs_get_inode(struct super_block *sb,
diff --git a/fs/ext4/symlink.c b/fs/ext4/symlink.c
index ca65d45c7f8d..32870881188e 100644
--- a/fs/ext4/symlink.c
+++ b/fs/ext4/symlink.c
@@ -29,7 +29,6 @@ static void *ext4_follow_link(struct dentry *dentry, struct nameidata *nd)
char *caddr, *paddr = NULL;
struct ext4_str cstr, pstr;
struct inode *inode = d_inode(dentry);
- struct ext4_fname_crypto_ctx *ctx = NULL;
struct ext4_encrypted_symlink_data *sd;
loff_t size = min_t(loff_t, i_size_read(inode), PAGE_SIZE - 1);
int res;
@@ -38,19 +37,17 @@ static void *ext4_follow_link(struct dentry *dentry, struct nameidata *nd)
if (!ext4_encrypted_inode(inode))
return page_follow_link_light(dentry, nd);
- ctx = ext4_get_fname_crypto_ctx(inode, inode->i_sb->s_blocksize);
- if (IS_ERR(ctx))
- return ctx;
+ res = ext4_setup_fname_crypto(inode);
+ if (res)
+ return ERR_PTR(res);
if (ext4_inode_is_fast_symlink(inode)) {
caddr = (char *) EXT4_I(inode)->i_data;
max_size = sizeof(EXT4_I(inode)->i_data);
} else {
cpage = read_mapping_page(inode->i_mapping, 0, NULL);
- if (IS_ERR(cpage)) {
- ext4_put_fname_crypto_ctx(&ctx);
+ if (IS_ERR(cpage))
return cpage;
- }
caddr = kmap(cpage);
caddr[size] = 0;
}
@@ -75,21 +72,19 @@ static void *ext4_follow_link(struct dentry *dentry, struct nameidata *nd)
}
pstr.name = paddr;
pstr.len = plen;
- res = _ext4_fname_disk_to_usr(ctx, NULL, &cstr, &pstr);
+ res = _ext4_fname_disk_to_usr(inode, NULL, &cstr, &pstr);
if (res < 0)
goto errout;
/* Null-terminate the name */
if (res <= plen)
paddr[res] = '\0';
nd_set_link(nd, paddr);
- ext4_put_fname_crypto_ctx(&ctx);
if (cpage) {
kunmap(cpage);
page_cache_release(cpage);
}
return NULL;
errout:
- ext4_put_fname_crypto_ctx(&ctx);
if (cpage) {
kunmap(cpage);
page_cache_release(cpage);