sanitize ecryptfs ->mount()
kill ecryptfs_read_super(), reorder code allowing to use normal d_alloc_root() instead of opencoding it. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
This commit is contained in:
Al Viro
parent
d61dcce297
commit
66cb76666d
|
|
@ -441,7 +441,6 @@ static struct dentry *ecryptfs_lookup(struct inode *ecryptfs_dir_inode,
|
|||
struct qstr lower_name;
|
||||
int rc = 0;
|
||||
|
||||
d_set_d_op(ecryptfs_dentry, &ecryptfs_dops);
|
||||
if ((ecryptfs_dentry->d_name.len == 1
|
||||
&& !strcmp(ecryptfs_dentry->d_name.name, "."))
|
||||
|| (ecryptfs_dentry->d_name.len == 2
|
||||
|
|
|
|||
|
|
@ -141,21 +141,9 @@ int ecryptfs_init_persistent_file(struct dentry *ecryptfs_dentry)
|
|||
return rc;
|
||||
}
|
||||
|
||||
/**
|
||||
* ecryptfs_interpose
|
||||
* @lower_dentry: Existing dentry in the lower filesystem
|
||||
* @dentry: ecryptfs' dentry
|
||||
* @sb: ecryptfs's super_block
|
||||
* @flags: flags to govern behavior of interpose procedure
|
||||
*
|
||||
* Interposes upper and lower dentries.
|
||||
*
|
||||
* Returns zero on success; non-zero otherwise
|
||||
*/
|
||||
int ecryptfs_interpose(struct dentry *lower_dentry, struct dentry *dentry,
|
||||
struct super_block *sb, u32 flags)
|
||||
static inode *ecryptfs_get_inode(struct inode *lower_inode,
|
||||
struct super_block *sb)
|
||||
{
|
||||
struct inode *lower_inode;
|
||||
struct inode *inode;
|
||||
int rc = 0;
|
||||
|
||||
|
|
@ -189,17 +177,38 @@ int ecryptfs_interpose(struct dentry *lower_dentry, struct dentry *dentry,
|
|||
if (special_file(lower_inode->i_mode))
|
||||
init_special_inode(inode, lower_inode->i_mode,
|
||||
lower_inode->i_rdev);
|
||||
d_set_d_op(dentry, &ecryptfs_dops);
|
||||
fsstack_copy_attr_all(inode, lower_inode);
|
||||
/* This size will be overwritten for real files w/ headers and
|
||||
* other metadata */
|
||||
fsstack_copy_inode_size(inode, lower_inode);
|
||||
return inode;
|
||||
out:
|
||||
return ERR_PTR(rc);
|
||||
}
|
||||
|
||||
/**
|
||||
* ecryptfs_interpose
|
||||
* @lower_dentry: Existing dentry in the lower filesystem
|
||||
* @dentry: ecryptfs' dentry
|
||||
* @sb: ecryptfs's super_block
|
||||
* @flags: flags to govern behavior of interpose procedure
|
||||
*
|
||||
* Interposes upper and lower dentries.
|
||||
*
|
||||
* Returns zero on success; non-zero otherwise
|
||||
*/
|
||||
int ecryptfs_interpose(struct dentry *lower_dentry, struct dentry *dentry,
|
||||
struct super_block *sb, u32 flags)
|
||||
{
|
||||
struct inode *lower_inode = lower_dentry->d_inode;
|
||||
struct inode *inode = ecryptfs_get_inode(lower_inode, sb);
|
||||
if (IS_ERR(inode)
|
||||
return PTR_ERR(inode);
|
||||
if (flags & ECRYPTFS_INTERPOSE_FLAG_D_ADD)
|
||||
d_add(dentry, inode);
|
||||
else
|
||||
d_instantiate(dentry, inode);
|
||||
out:
|
||||
return rc;
|
||||
return 0;
|
||||
}
|
||||
|
||||
enum { ecryptfs_opt_sig, ecryptfs_opt_ecryptfs_sig,
|
||||
|
|
@ -491,60 +500,12 @@ out:
|
|||
struct kmem_cache *ecryptfs_sb_info_cache;
|
||||
static struct file_system_type ecryptfs_fs_type;
|
||||
|
||||
/**
|
||||
* ecryptfs_read_super
|
||||
* @sb: The ecryptfs super block
|
||||
* @dev_name: The path to mount over
|
||||
*
|
||||
* Read the super block of the lower filesystem, and use
|
||||
* ecryptfs_interpose to create our initial inode and super block
|
||||
* struct.
|
||||
*/
|
||||
static int ecryptfs_read_super(struct super_block *sb, const char *dev_name)
|
||||
{
|
||||
struct path path;
|
||||
int rc;
|
||||
|
||||
rc = kern_path(dev_name, LOOKUP_FOLLOW | LOOKUP_DIRECTORY, &path);
|
||||
if (rc) {
|
||||
ecryptfs_printk(KERN_WARNING, "path_lookup() failed\n");
|
||||
goto out;
|
||||
}
|
||||
if (path.dentry->d_sb->s_type == &ecryptfs_fs_type) {
|
||||
rc = -EINVAL;
|
||||
printk(KERN_ERR "Mount on filesystem of type "
|
||||
"eCryptfs explicitly disallowed due to "
|
||||
"known incompatibilities\n");
|
||||
goto out_free;
|
||||
}
|
||||
ecryptfs_set_superblock_lower(sb, path.dentry->d_sb);
|
||||
sb->s_maxbytes = path.dentry->d_sb->s_maxbytes;
|
||||
sb->s_blocksize = path.dentry->d_sb->s_blocksize;
|
||||
ecryptfs_set_dentry_lower(sb->s_root, path.dentry);
|
||||
ecryptfs_set_dentry_lower_mnt(sb->s_root, path.mnt);
|
||||
rc = ecryptfs_interpose(path.dentry, sb->s_root, sb, 0);
|
||||
if (rc)
|
||||
goto out_free;
|
||||
rc = 0;
|
||||
goto out;
|
||||
out_free:
|
||||
path_put(&path);
|
||||
out:
|
||||
return rc;
|
||||
}
|
||||
|
||||
/**
|
||||
* ecryptfs_get_sb
|
||||
* @fs_type
|
||||
* @flags
|
||||
* @dev_name: The path to mount over
|
||||
* @raw_data: The options passed into the kernel
|
||||
*
|
||||
* The whole ecryptfs_get_sb process is broken into 3 functions:
|
||||
* ecryptfs_parse_options(): handle options passed to ecryptfs, if any
|
||||
* ecryptfs_read_super(): this accesses the lower filesystem and uses
|
||||
* ecryptfs_interpose to perform most of the linking
|
||||
* ecryptfs_interpose(): links the lower filesystem into ecryptfs (inode.c)
|
||||
*/
|
||||
static struct dentry *ecryptfs_mount(struct file_system_type *fs_type, int flags,
|
||||
const char *dev_name, void *raw_data)
|
||||
|
|
@ -553,6 +514,8 @@ static struct dentry *ecryptfs_mount(struct file_system_type *fs_type, int flags
|
|||
struct ecryptfs_sb_info *sbi;
|
||||
struct ecryptfs_dentry_info *root_info;
|
||||
const char *err = "Getting sb failed";
|
||||
struct inode *inode;
|
||||
struct path path;
|
||||
int rc;
|
||||
|
||||
sbi = kmem_cache_zalloc(ecryptfs_sb_info_cache, GFP_KERNEL);
|
||||
|
|
@ -575,10 +538,8 @@ static struct dentry *ecryptfs_mount(struct file_system_type *fs_type, int flags
|
|||
|
||||
s->s_flags = flags;
|
||||
rc = bdi_setup_and_register(&sbi->bdi, "ecryptfs", BDI_CAP_MAP_COPY);
|
||||
if (rc) {
|
||||
deactivate_locked_super(s);
|
||||
goto out;
|
||||
}
|
||||
if (rc)
|
||||
goto out1;
|
||||
|
||||
ecryptfs_set_superblock_private(s, sbi);
|
||||
s->s_bdi = &sbi->bdi;
|
||||
|
|
@ -586,34 +547,54 @@ static struct dentry *ecryptfs_mount(struct file_system_type *fs_type, int flags
|
|||
/* ->kill_sb() will take care of sbi after that point */
|
||||
sbi = NULL;
|
||||
s->s_op = &ecryptfs_sops;
|
||||
s->s_d_op = &ecryptfs_dops;
|
||||
|
||||
err = "Reading sb failed";
|
||||
rc = kern_path(dev_name, LOOKUP_FOLLOW | LOOKUP_DIRECTORY, &path);
|
||||
if (rc) {
|
||||
ecryptfs_printk(KERN_WARNING, "kern_path() failed\n");
|
||||
goto out1;
|
||||
}
|
||||
if (path.dentry->d_sb->s_type == &ecryptfs_fs_type) {
|
||||
rc = -EINVAL;
|
||||
printk(KERN_ERR "Mount on filesystem of type "
|
||||
"eCryptfs explicitly disallowed due to "
|
||||
"known incompatibilities\n");
|
||||
goto out_free;
|
||||
}
|
||||
ecryptfs_set_superblock_lower(s, path.dentry->d_sb);
|
||||
s->s_maxbytes = path.dentry->d_sb->s_maxbytes;
|
||||
s->s_blocksize = path.dentry->d_sb->s_blocksize;
|
||||
|
||||
inode = ecryptfs_get_inode(path.dentry->d_inode, s);
|
||||
rc = PTR_ERR(inode);
|
||||
if (IS_ERR(inode))
|
||||
goto out_free;
|
||||
|
||||
s->s_root = d_alloc_root(inode);
|
||||
if (!s->s_root) {
|
||||
iput(inode);
|
||||
rc = -ENOMEM;
|
||||
goto out_free;
|
||||
}
|
||||
|
||||
rc = -ENOMEM;
|
||||
s->s_root = d_alloc(NULL, &(const struct qstr) {
|
||||
.hash = 0,.name = "/",.len = 1});
|
||||
if (!s->s_root) {
|
||||
deactivate_locked_super(s);
|
||||
goto out;
|
||||
}
|
||||
d_set_d_op(s->s_root, &ecryptfs_dops);
|
||||
s->s_root->d_sb = s;
|
||||
s->s_root->d_parent = s->s_root;
|
||||
|
||||
root_info = kmem_cache_zalloc(ecryptfs_dentry_info_cache, GFP_KERNEL);
|
||||
if (!root_info) {
|
||||
deactivate_locked_super(s);
|
||||
goto out;
|
||||
}
|
||||
if (!root_info)
|
||||
goto out_free;
|
||||
|
||||
/* ->kill_sb() will take care of root_info */
|
||||
ecryptfs_set_dentry_private(s->s_root, root_info);
|
||||
ecryptfs_set_dentry_lower(s->s_root, path.dentry);
|
||||
ecryptfs_set_dentry_lower_mnt(s->s_root, path.mnt);
|
||||
|
||||
s->s_flags |= MS_ACTIVE;
|
||||
rc = ecryptfs_read_super(s, dev_name);
|
||||
if (rc) {
|
||||
deactivate_locked_super(s);
|
||||
err = "Reading sb failed";
|
||||
goto out;
|
||||
}
|
||||
return dget(s->s_root);
|
||||
|
||||
out_free:
|
||||
path_put(&path);
|
||||
out1:
|
||||
deactivate_locked_super(s);
|
||||
out:
|
||||
if (sbi) {
|
||||
ecryptfs_destroy_mount_crypt_stat(&sbi->mount_crypt_stat);
|
||||
|
|
|
|||
Reference in New Issue