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-rw-r--r--fs/ecryptfs/ecryptfs_kernel.h5
-rw-r--r--fs/ecryptfs/file.c22
-rw-r--r--fs/ecryptfs/inode.c30
-rw-r--r--fs/ecryptfs/kthread.c6
-rw-r--r--fs/ecryptfs/main.c72
-rw-r--r--fs/ecryptfs/super.c16
6 files changed, 92 insertions, 59 deletions
diff --git a/fs/ecryptfs/ecryptfs_kernel.h b/fs/ecryptfs/ecryptfs_kernel.h
index bd3cafd0949..380bee1094c 100644
--- a/fs/ecryptfs/ecryptfs_kernel.h
+++ b/fs/ecryptfs/ecryptfs_kernel.h
@@ -295,6 +295,8 @@ struct ecryptfs_crypt_stat {
struct ecryptfs_inode_info {
struct inode vfs_inode;
struct inode *wii_inode;
+ struct mutex lower_file_mutex;
+ atomic_t lower_file_count;
struct file *lower_file;
struct ecryptfs_crypt_stat crypt_stat;
};
@@ -757,7 +759,8 @@ int ecryptfs_privileged_open(struct file **lower_file,
struct dentry *lower_dentry,
struct vfsmount *lower_mnt,
const struct cred *cred);
-int ecryptfs_init_persistent_file(struct dentry *ecryptfs_dentry);
+int ecryptfs_get_lower_file(struct dentry *ecryptfs_dentry);
+void ecryptfs_put_lower_file(struct inode *inode);
int
ecryptfs_write_tag_70_packet(char *dest, size_t *remaining_bytes,
size_t *packet_size,
diff --git a/fs/ecryptfs/file.c b/fs/ecryptfs/file.c
index cedc913d11b..146c4edff70 100644
--- a/fs/ecryptfs/file.c
+++ b/fs/ecryptfs/file.c
@@ -191,10 +191,10 @@ static int ecryptfs_open(struct inode *inode, struct file *file)
| ECRYPTFS_ENCRYPTED);
}
mutex_unlock(&crypt_stat->cs_mutex);
- rc = ecryptfs_init_persistent_file(ecryptfs_dentry);
+ rc = ecryptfs_get_lower_file(ecryptfs_dentry);
if (rc) {
printk(KERN_ERR "%s: Error attempting to initialize "
- "the persistent file for the dentry with name "
+ "the lower file for the dentry with name "
"[%s]; rc = [%d]\n", __func__,
ecryptfs_dentry->d_name.name, rc);
goto out_free;
@@ -202,9 +202,9 @@ static int ecryptfs_open(struct inode *inode, struct file *file)
if ((ecryptfs_inode_to_private(inode)->lower_file->f_flags & O_ACCMODE)
== O_RDONLY && (file->f_flags & O_ACCMODE) != O_RDONLY) {
rc = -EPERM;
- printk(KERN_WARNING "%s: Lower persistent file is RO; eCryptfs "
+ printk(KERN_WARNING "%s: Lower file is RO; eCryptfs "
"file must hence be opened RO\n", __func__);
- goto out_free;
+ goto out_put;
}
ecryptfs_set_file_lower(
file, ecryptfs_inode_to_private(inode)->lower_file);
@@ -232,7 +232,7 @@ static int ecryptfs_open(struct inode *inode, struct file *file)
"Plaintext passthrough mode is not "
"enabled; returning -EIO\n");
mutex_unlock(&crypt_stat->cs_mutex);
- goto out_free;
+ goto out_put;
}
rc = 0;
crypt_stat->flags &= ~(ECRYPTFS_ENCRYPTED);
@@ -245,6 +245,8 @@ static int ecryptfs_open(struct inode *inode, struct file *file)
"[0x%.16lx] size: [0x%.16llx]\n", inode, inode->i_ino,
(unsigned long long)i_size_read(inode));
goto out;
+out_put:
+ ecryptfs_put_lower_file(inode);
out_free:
kmem_cache_free(ecryptfs_file_info_cache,
ecryptfs_file_to_private(file));
@@ -254,17 +256,13 @@ out:
static int ecryptfs_flush(struct file *file, fl_owner_t td)
{
- int rc = 0;
- struct file *lower_file = NULL;
-
- lower_file = ecryptfs_file_to_lower(file);
- if (lower_file->f_op && lower_file->f_op->flush)
- rc = lower_file->f_op->flush(lower_file, td);
- return rc;
+ return file->f_mode & FMODE_WRITE
+ ? filemap_write_and_wait(file->f_mapping) : 0;
}
static int ecryptfs_release(struct inode *inode, struct file *file)
{
+ ecryptfs_put_lower_file(inode);
kmem_cache_free(ecryptfs_file_info_cache,
ecryptfs_file_to_private(file));
return 0;
diff --git a/fs/ecryptfs/inode.c b/fs/ecryptfs/inode.c
index 72d35764959..f6b388638c3 100644
--- a/fs/ecryptfs/inode.c
+++ b/fs/ecryptfs/inode.c
@@ -168,19 +168,18 @@ static int ecryptfs_initialize_file(struct dentry *ecryptfs_dentry)
"context; rc = [%d]\n", rc);
goto out;
}
- rc = ecryptfs_init_persistent_file(ecryptfs_dentry);
+ rc = ecryptfs_get_lower_file(ecryptfs_dentry);
if (rc) {
printk(KERN_ERR "%s: Error attempting to initialize "
- "the persistent file for the dentry with name "
+ "the lower file for the dentry with name "
"[%s]; rc = [%d]\n", __func__,
ecryptfs_dentry->d_name.name, rc);
goto out;
}
rc = ecryptfs_write_metadata(ecryptfs_dentry);
- if (rc) {
+ if (rc)
printk(KERN_ERR "Error writing headers; rc = [%d]\n", rc);
- goto out;
- }
+ ecryptfs_put_lower_file(ecryptfs_dentry->d_inode);
out:
return rc;
}
@@ -230,7 +229,7 @@ int ecryptfs_lookup_and_interpose_lower(struct dentry *ecryptfs_dentry,
struct ecryptfs_crypt_stat *crypt_stat;
char *page_virt = NULL;
u64 file_size;
- int rc = 0;
+ int put_lower = 0, rc = 0;
lower_dir_dentry = lower_dentry->d_parent;
lower_mnt = mntget(ecryptfs_dentry_to_lower_mnt(
@@ -277,14 +276,15 @@ int ecryptfs_lookup_and_interpose_lower(struct dentry *ecryptfs_dentry,
rc = -ENOMEM;
goto out;
}
- rc = ecryptfs_init_persistent_file(ecryptfs_dentry);
+ rc = ecryptfs_get_lower_file(ecryptfs_dentry);
if (rc) {
printk(KERN_ERR "%s: Error attempting to initialize "
- "the persistent file for the dentry with name "
+ "the lower file for the dentry with name "
"[%s]; rc = [%d]\n", __func__,
ecryptfs_dentry->d_name.name, rc);
goto out_free_kmem;
}
+ put_lower = 1;
crypt_stat = &ecryptfs_inode_to_private(
ecryptfs_dentry->d_inode)->crypt_stat;
/* TODO: lock for crypt_stat comparison */
@@ -322,6 +322,8 @@ out_put:
mntput(lower_mnt);
d_drop(ecryptfs_dentry);
out:
+ if (put_lower)
+ ecryptfs_put_lower_file(ecryptfs_dentry->d_inode);
return rc;
}
@@ -757,8 +759,11 @@ static int truncate_upper(struct dentry *dentry, struct iattr *ia,
if (unlikely((ia->ia_size == i_size))) {
lower_ia->ia_valid &= ~ATTR_SIZE;
- goto out;
+ return 0;
}
+ rc = ecryptfs_get_lower_file(dentry);
+ if (rc)
+ return rc;
crypt_stat = &ecryptfs_inode_to_private(dentry->d_inode)->crypt_stat;
/* Switch on growing or shrinking file */
if (ia->ia_size > i_size) {
@@ -836,6 +841,7 @@ static int truncate_upper(struct dentry *dentry, struct iattr *ia,
lower_ia->ia_valid &= ~ATTR_SIZE;
}
out:
+ ecryptfs_put_lower_file(inode);
return rc;
}
@@ -911,7 +917,13 @@ static int ecryptfs_setattr(struct dentry *dentry, struct iattr *ia)
mount_crypt_stat = &ecryptfs_superblock_to_private(
dentry->d_sb)->mount_crypt_stat;
+ rc = ecryptfs_get_lower_file(dentry);
+ if (rc) {
+ mutex_unlock(&crypt_stat->cs_mutex);
+ goto out;
+ }
rc = ecryptfs_read_metadata(dentry);
+ ecryptfs_put_lower_file(inode);
if (rc) {
if (!(mount_crypt_stat->flags
& ECRYPTFS_PLAINTEXT_PASSTHROUGH_ENABLED)) {
diff --git a/fs/ecryptfs/kthread.c b/fs/ecryptfs/kthread.c
index 0851ab6980f..69f994a7d52 100644
--- a/fs/ecryptfs/kthread.c
+++ b/fs/ecryptfs/kthread.c
@@ -44,7 +44,7 @@ static struct task_struct *ecryptfs_kthread;
* @ignored: ignored
*
* The eCryptfs kernel thread that has the responsibility of getting
- * the lower persistent file with RW permissions.
+ * the lower file with RW permissions.
*
* Returns zero on success; non-zero otherwise
*/
@@ -141,8 +141,8 @@ int ecryptfs_privileged_open(struct file **lower_file,
int rc = 0;
/* Corresponding dput() and mntput() are done when the
- * persistent file is fput() when the eCryptfs inode is
- * destroyed. */
+ * lower file is fput() when all eCryptfs files for the inode are
+ * released. */
dget(lower_dentry);
mntget(lower_mnt);
flags |= IS_RDONLY(lower_dentry->d_inode) ? O_RDONLY : O_RDWR;
diff --git a/fs/ecryptfs/main.c b/fs/ecryptfs/main.c
index fdb2eb0ad09..89b93389af8 100644
--- a/fs/ecryptfs/main.c
+++ b/fs/ecryptfs/main.c
@@ -96,7 +96,7 @@ void __ecryptfs_printk(const char *fmt, ...)
}
/**
- * ecryptfs_init_persistent_file
+ * ecryptfs_init_lower_file
* @ecryptfs_dentry: Fully initialized eCryptfs dentry object, with
* the lower dentry and the lower mount set
*
@@ -104,42 +104,70 @@ void __ecryptfs_printk(const char *fmt, ...)
* inode. All I/O operations to the lower inode occur through that
* file. When the first eCryptfs dentry that interposes with the first
* lower dentry for that inode is created, this function creates the
- * persistent file struct and associates it with the eCryptfs
- * inode. When the eCryptfs inode is destroyed, the file is closed.
+ * lower file struct and associates it with the eCryptfs
+ * inode. When all eCryptfs files associated with the inode are released, the
+ * file is closed.
*
- * The persistent file will be opened with read/write permissions, if
+ * The lower file will be opened with read/write permissions, if
* possible. Otherwise, it is opened read-only.
*
- * This function does nothing if a lower persistent file is already
+ * This function does nothing if a lower file is already
* associated with the eCryptfs inode.
*
* Returns zero on success; non-zero otherwise
*/
-int ecryptfs_init_persistent_file(struct dentry *ecryptfs_dentry)
+static int ecryptfs_init_lower_file(struct dentry *dentry,
+ struct file **lower_file)
{
const struct cred *cred = current_cred();
- struct ecryptfs_inode_info *inode_info =
- ecryptfs_inode_to_private(ecryptfs_dentry->d_inode);
- int rc = 0;
+ struct dentry *lower_dentry = ecryptfs_dentry_to_lower(dentry);
+ struct vfsmount *lower_mnt = ecryptfs_dentry_to_lower_mnt(dentry);
+ int rc;
- if (!inode_info->lower_file) {
- struct dentry *lower_dentry;
- struct vfsmount *lower_mnt =
- ecryptfs_dentry_to_lower_mnt(ecryptfs_dentry);
+ rc = ecryptfs_privileged_open(lower_file, lower_dentry, lower_mnt,
+ cred);
+ if (rc) {
+ printk(KERN_ERR "Error opening lower file "
+ "for lower_dentry [0x%p] and lower_mnt [0x%p]; "
+ "rc = [%d]\n", lower_dentry, lower_mnt, rc);
+ (*lower_file) = NULL;
+ }
+ return rc;
+}
- lower_dentry = ecryptfs_dentry_to_lower(ecryptfs_dentry);
- rc = ecryptfs_privileged_open(&inode_info->lower_file,
- lower_dentry, lower_mnt, cred);
- if (rc) {
- printk(KERN_ERR "Error opening lower persistent file "
- "for lower_dentry [0x%p] and lower_mnt [0x%p]; "
- "rc = [%d]\n", lower_dentry, lower_mnt, rc);
- inode_info->lower_file = NULL;
- }
+int ecryptfs_get_lower_file(struct dentry *dentry)
+{
+ struct ecryptfs_inode_info *inode_info =
+ ecryptfs_inode_to_private(dentry->d_inode);
+ int count, rc = 0;
+
+ mutex_lock(&inode_info->lower_file_mutex);
+ count = atomic_inc_return(&inode_info->lower_file_count);
+ if (WARN_ON_ONCE(count < 1))
+ rc = -EINVAL;
+ else if (count == 1) {
+ rc = ecryptfs_init_lower_file(dentry,
+ &inode_info->lower_file);
+ if (rc)
+ atomic_set(&inode_info->lower_file_count, 0);
}
+ mutex_unlock(&inode_info->lower_file_mutex);
return rc;
}
+void ecryptfs_put_lower_file(struct inode *inode)
+{
+ struct ecryptfs_inode_info *inode_info;
+
+ inode_info = ecryptfs_inode_to_private(inode);
+ if (atomic_dec_and_mutex_lock(&inode_info->lower_file_count,
+ &inode_info->lower_file_mutex)) {
+ fput(inode_info->lower_file);
+ inode_info->lower_file = NULL;
+ mutex_unlock(&inode_info->lower_file_mutex);
+ }
+}
+
static struct inode *ecryptfs_get_inode(struct inode *lower_inode,
struct super_block *sb)
{
diff --git a/fs/ecryptfs/super.c b/fs/ecryptfs/super.c
index bacc882e1ae..245b517bf1b 100644
--- a/fs/ecryptfs/super.c
+++ b/fs/ecryptfs/super.c
@@ -55,6 +55,8 @@ static struct inode *ecryptfs_alloc_inode(struct super_block *sb)
if (unlikely(!inode_info))
goto out;
ecryptfs_init_crypt_stat(&inode_info->crypt_stat);
+ mutex_init(&inode_info->lower_file_mutex);
+ atomic_set(&inode_info->lower_file_count, 0);
inode_info->lower_file = NULL;
inode = &inode_info->vfs_inode;
out:
@@ -77,8 +79,7 @@ static void ecryptfs_i_callback(struct rcu_head *head)
*
* This is used during the final destruction of the inode. All
* allocation of memory related to the inode, including allocated
- * memory in the crypt_stat struct, will be released here. This
- * function also fput()'s the persistent file for the lower inode.
+ * memory in the crypt_stat struct, will be released here.
* There should be no chance that this deallocation will be missed.
*/
static void ecryptfs_destroy_inode(struct inode *inode)
@@ -86,16 +87,7 @@ static void ecryptfs_destroy_inode(struct inode *inode)
struct ecryptfs_inode_info *inode_info;
inode_info = ecryptfs_inode_to_private(inode);
- if (inode_info->lower_file) {
- struct dentry *lower_dentry =
- inode_info->lower_file->f_dentry;
-
- BUG_ON(!lower_dentry);
- if (lower_dentry->d_inode) {
- fput(inode_info->lower_file);
- inode_info->lower_file = NULL;
- }
- }
+ BUG_ON(inode_info->lower_file);
ecryptfs_destroy_crypt_stat(&inode_info->crypt_stat);
call_rcu(&inode->i_rcu, ecryptfs_i_callback);
}
generated by cgit v1.2.3-18-g5258 (git 2.32.0) at 2024-12-02 16:18:15 +0000