#include <linux/slab.h>
#include <linux/fs.h>
#include <linux/namei.h>
-#include <linux/quotaops.h>
#include <linux/pagemap.h>
#include <linux/fsnotify.h>
#include <linux/personality.h>
static __always_inline int __vfs_follow_link(struct nameidata *nd, const char *link)
{
- int res = 0;
- char *name;
if (IS_ERR(link))
goto fail;
path_get(&nd->root);
}
- res = link_path_walk(link, nd);
- if (nd->depth || res || nd->last_type!=LAST_NORM)
- return res;
- /*
- * If it is an iterative symlinks resolution in open_namei() we
- * have to copy the last component. And all that crap because of
- * bloody create() on broken symlinks. Furrfu...
- */
- name = __getname();
- if (unlikely(!name)) {
- path_put(&nd->path);
- return -ENOMEM;
- }
- strcpy(name, nd->last.name);
- nd->last.name = name;
- return 0;
+ return link_path_walk(link, nd);
fail:
path_put(&nd->path);
return PTR_ERR(link);
static inline void path_to_nameidata(struct path *path, struct nameidata *nd)
{
dput(nd->path.dentry);
- if (nd->path.mnt != path->mnt)
+ if (nd->path.mnt != path->mnt) {
mntput(nd->path.mnt);
- nd->path.mnt = path->mnt;
+ nd->path.mnt = path->mnt;
+ }
nd->path.dentry = path->dentry;
}
-static __always_inline int __do_follow_link(struct path *path, struct nameidata *nd)
+static __always_inline int
+__do_follow_link(struct path *path, struct nameidata *nd, void **p)
{
int error;
- void *cookie;
struct dentry *dentry = path->dentry;
touch_atime(path->mnt, dentry);
}
mntget(path->mnt);
nd->last_type = LAST_BIND;
- cookie = dentry->d_inode->i_op->follow_link(dentry, nd);
- error = PTR_ERR(cookie);
- if (!IS_ERR(cookie)) {
+ *p = dentry->d_inode->i_op->follow_link(dentry, nd);
+ error = PTR_ERR(*p);
+ if (!IS_ERR(*p)) {
char *s = nd_get_link(nd);
error = 0;
if (s)
if (error)
path_put(&nd->path);
}
- if (dentry->d_inode->i_op->put_link)
- dentry->d_inode->i_op->put_link(dentry, nd, cookie);
}
return error;
}
*/
static inline int do_follow_link(struct path *path, struct nameidata *nd)
{
+ void *cookie;
int err = -ELOOP;
if (current->link_count >= MAX_NESTED_LINKS)
goto loop;
current->link_count++;
current->total_link_count++;
nd->depth++;
- err = __do_follow_link(path, nd);
+ err = __do_follow_link(path, nd, &cookie);
+ if (!IS_ERR(cookie) && path->dentry->d_inode->i_op->put_link)
+ path->dentry->d_inode->i_op->put_link(path->dentry, nd, cookie);
path_put(path);
current->link_count--;
nd->depth--;
return inode_permission(dir, MAY_WRITE | MAY_EXEC);
}
-/*
- * O_DIRECTORY translates into forcing a directory lookup.
- */
-static inline int lookup_flags(unsigned int f)
-{
- unsigned long retval = LOOKUP_FOLLOW;
-
- if (f & O_NOFOLLOW)
- retval &= ~LOOKUP_FOLLOW;
-
- if (f & O_DIRECTORY)
- retval |= LOOKUP_DIRECTORY;
-
- return retval;
-}
-
/*
* p1 and p2 should be directories on the same fs.
*/
error = security_inode_create(dir, dentry, mode);
if (error)
return error;
- vfs_dq_init(dir);
error = dir->i_op->create(dir, dentry, mode, nd);
if (!error)
fsnotify_create(dir, dentry);
*/
error = locks_verify_locked(inode);
if (!error)
- error = security_path_truncate(path, 0,
- ATTR_MTIME|ATTR_CTIME|ATTR_OPEN);
+ error = security_path_truncate(path);
if (!error) {
error = do_truncate(path->dentry, 0,
ATTR_MTIME|ATTR_CTIME|ATTR_OPEN,
}
static struct file *finish_open(struct nameidata *nd,
- int open_flag, int flag, int acc_mode)
+ int open_flag, int acc_mode)
{
struct file *filp;
int will_truncate;
int error;
- will_truncate = open_will_truncate(flag, nd->path.dentry->d_inode);
+ will_truncate = open_will_truncate(open_flag, nd->path.dentry->d_inode);
if (will_truncate) {
error = mnt_want_write(nd->path.mnt);
if (error)
}
}
if (!IS_ERR(filp)) {
- if (acc_mode & MAY_WRITE)
- vfs_dq_init(nd->path.dentry->d_inode);
-
if (will_truncate) {
error = handle_truncate(&nd->path);
if (error) {
}
static struct file *do_last(struct nameidata *nd, struct path *path,
- int open_flag, int flag, int acc_mode,
- int mode, const char *pathname,
- struct dentry *dir, int *is_link)
+ int open_flag, int acc_mode,
+ int mode, const char *pathname)
{
+ struct dentry *dir = nd->path.dentry;
struct file *filp;
- int error;
+ int error = -EISDIR;
+
+ switch (nd->last_type) {
+ case LAST_DOTDOT:
+ follow_dotdot(nd);
+ dir = nd->path.dentry;
+ case LAST_DOT:
+ if (nd->path.mnt->mnt_sb->s_type->fs_flags & FS_REVAL_DOT) {
+ if (!dir->d_op->d_revalidate(dir, nd)) {
+ error = -ESTALE;
+ goto exit;
+ }
+ }
+ /* fallthrough */
+ case LAST_ROOT:
+ if (open_flag & O_CREAT)
+ goto exit;
+ /* fallthrough */
+ case LAST_BIND:
+ audit_inode(pathname, dir);
+ goto ok;
+ }
+
+ /* trailing slashes? */
+ if (nd->last.name[nd->last.len]) {
+ if (open_flag & O_CREAT)
+ goto exit;
+ nd->flags |= LOOKUP_DIRECTORY | LOOKUP_FOLLOW;
+ }
+
+ /* just plain open? */
+ if (!(open_flag & O_CREAT)) {
+ error = do_lookup(nd, &nd->last, path);
+ if (error)
+ goto exit;
+ error = -ENOENT;
+ if (!path->dentry->d_inode)
+ goto exit_dput;
+ if (path->dentry->d_inode->i_op->follow_link)
+ return NULL;
+ error = -ENOTDIR;
+ if (nd->flags & LOOKUP_DIRECTORY) {
+ if (!path->dentry->d_inode->i_op->lookup)
+ goto exit_dput;
+ }
+ path_to_nameidata(path, nd);
+ audit_inode(pathname, nd->path.dentry);
+ goto ok;
+ }
+
+ /* OK, it's O_CREAT */
+ mutex_lock(&dir->d_inode->i_mutex);
- *is_link = 0;
+ path->dentry = lookup_hash(nd);
+ path->mnt = nd->path.mnt;
error = PTR_ERR(path->dentry);
if (IS_ERR(path->dentry)) {
audit_inode(pathname, path->dentry);
error = -EEXIST;
- if (flag & O_EXCL)
+ if (open_flag & O_EXCL)
goto exit_dput;
if (__follow_mount(path)) {
error = -ELOOP;
- if (flag & O_NOFOLLOW)
+ if (open_flag & O_NOFOLLOW)
goto exit_dput;
}
error = -ENOENT;
if (!path->dentry->d_inode)
goto exit_dput;
- if (path->dentry->d_inode->i_op->follow_link) {
- *is_link = 1;
+
+ if (path->dentry->d_inode->i_op->follow_link)
return NULL;
- }
path_to_nameidata(path, nd);
error = -EISDIR;
if (S_ISDIR(path->dentry->d_inode->i_mode))
goto exit;
- filp = finish_open(nd, open_flag, flag, acc_mode);
+ok:
+ filp = finish_open(nd, open_flag, acc_mode);
return filp;
exit_mutex_unlock:
struct nameidata nd;
int error;
struct path path;
- struct dentry *dir;
int count = 0;
int flag = open_to_namei_flags(open_flag);
int force_reval = 0;
- int is_link;
+
+ if (!(open_flag & O_CREAT))
+ mode = 0;
/*
* O_SYNC is implemented as __O_SYNC|O_DSYNC. As many places only
acc_mode = MAY_OPEN | ACC_MODE(open_flag);
/* O_TRUNC implies we need access checks for write permissions */
- if (flag & O_TRUNC)
+ if (open_flag & O_TRUNC)
acc_mode |= MAY_WRITE;
/* Allow the LSM permission hook to distinguish append
access from general write access. */
- if (flag & O_APPEND)
+ if (open_flag & O_APPEND)
acc_mode |= MAY_APPEND;
- /*
- * The simplest case - just a plain lookup.
- */
- if (!(flag & O_CREAT)) {
- filp = get_empty_filp();
-
- if (filp == NULL)
- return ERR_PTR(-ENFILE);
- nd.intent.open.file = filp;
- filp->f_flags = open_flag;
- nd.intent.open.flags = flag;
- nd.intent.open.create_mode = 0;
- error = do_path_lookup(dfd, pathname,
- lookup_flags(flag)|LOOKUP_OPEN, &nd);
- if (IS_ERR(nd.intent.open.file)) {
- if (error == 0) {
- error = PTR_ERR(nd.intent.open.file);
- path_put(&nd.path);
- }
- } else if (error)
- release_open_intent(&nd);
- if (error)
- return ERR_PTR(error);
- goto ok;
- }
-
- /*
- * Create - we need to know the parent.
- */
+ /* find the parent */
reval:
error = path_init(dfd, pathname, LOOKUP_PARENT, &nd);
if (error)
return ERR_PTR(error);
if (force_reval)
nd.flags |= LOOKUP_REVAL;
- error = path_walk(pathname, &nd);
+
+ current->total_link_count = 0;
+ error = link_path_walk(pathname, &nd);
if (error) {
- if (nd.root.mnt)
- path_put(&nd.root);
- return ERR_PTR(error);
+ filp = ERR_PTR(error);
+ goto out;
}
- if (unlikely(!audit_dummy_context()))
+ if (unlikely(!audit_dummy_context()) && (open_flag & O_CREAT))
audit_inode(pathname, nd.path.dentry);
/*
- * We have the parent and last component. First of all, check
- * that we are not asked to creat(2) an obvious directory - that
- * will not do.
+ * We have the parent and last component.
*/
- error = -EISDIR;
- if (nd.last_type != LAST_NORM || nd.last.name[nd.last.len])
- goto exit_parent;
error = -ENFILE;
filp = get_empty_filp();
filp->f_flags = open_flag;
nd.intent.open.flags = flag;
nd.intent.open.create_mode = mode;
- dir = nd.path.dentry;
nd.flags &= ~LOOKUP_PARENT;
- nd.flags |= LOOKUP_CREATE | LOOKUP_OPEN;
- if (flag & O_EXCL)
- nd.flags |= LOOKUP_EXCL;
- mutex_lock(&dir->d_inode->i_mutex);
- path.dentry = lookup_hash(&nd);
- path.mnt = nd.path.mnt;
-
-do_last:
- filp = do_last(&nd, &path, open_flag, flag, acc_mode, mode,
- pathname, dir, &is_link);
- if (is_link)
- goto do_link;
- if (nd.root.mnt)
- path_put(&nd.root);
- return filp;
-
-ok:
- filp = finish_open(&nd, open_flag, flag, acc_mode);
+ nd.flags |= LOOKUP_OPEN;
+ if (open_flag & O_CREAT) {
+ nd.flags |= LOOKUP_CREATE;
+ if (open_flag & O_EXCL)
+ nd.flags |= LOOKUP_EXCL;
+ }
+ if (open_flag & O_DIRECTORY)
+ nd.flags |= LOOKUP_DIRECTORY;
+ if (!(open_flag & O_NOFOLLOW))
+ nd.flags |= LOOKUP_FOLLOW;
+ filp = do_last(&nd, &path, open_flag, acc_mode, mode, pathname);
+ while (unlikely(!filp)) { /* trailing symlink */
+ struct path holder;
+ struct inode *inode = path.dentry->d_inode;
+ void *cookie;
+ error = -ELOOP;
+ /* S_ISDIR part is a temporary automount kludge */
+ if (!(nd.flags & LOOKUP_FOLLOW) && !S_ISDIR(inode->i_mode))
+ goto exit_dput;
+ if (count++ == 32)
+ goto exit_dput;
+ /*
+ * This is subtle. Instead of calling do_follow_link() we do
+ * the thing by hands. The reason is that this way we have zero
+ * link_count and path_walk() (called from ->follow_link)
+ * honoring LOOKUP_PARENT. After that we have the parent and
+ * last component, i.e. we are in the same situation as after
+ * the first path_walk(). Well, almost - if the last component
+ * is normal we get its copy stored in nd->last.name and we will
+ * have to putname() it when we are done. Procfs-like symlinks
+ * just set LAST_BIND.
+ */
+ nd.flags |= LOOKUP_PARENT;
+ error = security_inode_follow_link(path.dentry, &nd);
+ if (error)
+ goto exit_dput;
+ error = __do_follow_link(&path, &nd, &cookie);
+ if (unlikely(error)) {
+ /* nd.path had been dropped */
+ if (!IS_ERR(cookie) && inode->i_op->put_link)
+ inode->i_op->put_link(path.dentry, &nd, cookie);
+ path_put(&path);
+ release_open_intent(&nd);
+ filp = ERR_PTR(error);
+ goto out;
+ }
+ holder = path;
+ nd.flags &= ~LOOKUP_PARENT;
+ filp = do_last(&nd, &path, open_flag, acc_mode, mode, pathname);
+ if (inode->i_op->put_link)
+ inode->i_op->put_link(holder.dentry, &nd, cookie);
+ path_put(&holder);
+ }
+out:
if (nd.root.mnt)
path_put(&nd.root);
+ if (filp == ERR_PTR(-ESTALE) && !force_reval) {
+ force_reval = 1;
+ goto reval;
+ }
return filp;
exit_dput:
path_put_conditional(&path, &nd);
-exit:
if (!IS_ERR(nd.intent.open.file))
release_open_intent(&nd);
exit_parent:
- if (nd.root.mnt)
- path_put(&nd.root);
path_put(&nd.path);
- return ERR_PTR(error);
-
-do_link:
- error = -ELOOP;
- if (flag & O_NOFOLLOW)
- goto exit_dput;
- /*
- * This is subtle. Instead of calling do_follow_link() we do the
- * thing by hands. The reason is that this way we have zero link_count
- * and path_walk() (called from ->follow_link) honoring LOOKUP_PARENT.
- * After that we have the parent and last component, i.e.
- * we are in the same situation as after the first path_walk().
- * Well, almost - if the last component is normal we get its copy
- * stored in nd->last.name and we will have to putname() it when we
- * are done. Procfs-like symlinks just set LAST_BIND.
- */
- nd.flags |= LOOKUP_PARENT;
- error = security_inode_follow_link(path.dentry, &nd);
- if (error)
- goto exit_dput;
- error = __do_follow_link(&path, &nd);
- path_put(&path);
- if (error) {
- /* Does someone understand code flow here? Or it is only
- * me so stupid? Anathema to whoever designed this non-sense
- * with "intent.open".
- */
- release_open_intent(&nd);
- if (nd.root.mnt)
- path_put(&nd.root);
- if (error == -ESTALE && !force_reval) {
- force_reval = 1;
- goto reval;
- }
- return ERR_PTR(error);
- }
- nd.flags &= ~LOOKUP_PARENT;
- if (nd.last_type == LAST_BIND)
- goto ok;
- error = -EISDIR;
- if (nd.last_type != LAST_NORM)
- goto exit;
- if (nd.last.name[nd.last.len]) {
- __putname(nd.last.name);
- goto exit;
- }
- error = -ELOOP;
- if (count++==32) {
- __putname(nd.last.name);
- goto exit;
- }
- dir = nd.path.dentry;
- mutex_lock(&dir->d_inode->i_mutex);
- path.dentry = lookup_hash(&nd);
- path.mnt = nd.path.mnt;
- __putname(nd.last.name);
- goto do_last;
+ filp = ERR_PTR(error);
+ goto out;
}
/**
if (error)
return error;
- vfs_dq_init(dir);
error = dir->i_op->mknod(dir, dentry, mode, dev);
if (!error)
fsnotify_create(dir, dentry);
if (error)
return error;
- vfs_dq_init(dir);
error = dir->i_op->mkdir(dir, dentry, mode);
if (!error)
fsnotify_mkdir(dir, dentry);
if (!dir->i_op->rmdir)
return -EPERM;
- vfs_dq_init(dir);
-
mutex_lock(&dentry->d_inode->i_mutex);
dentry_unhash(dentry);
if (d_mountpoint(dentry))
error = security_inode_rmdir(dir, dentry);
if (!error) {
error = dir->i_op->rmdir(dir, dentry);
- if (!error)
+ if (!error) {
dentry->d_inode->i_flags |= S_DEAD;
+ dont_mount(dentry);
+ }
}
}
mutex_unlock(&dentry->d_inode->i_mutex);
if (!dir->i_op->unlink)
return -EPERM;
- vfs_dq_init(dir);
-
mutex_lock(&dentry->d_inode->i_mutex);
if (d_mountpoint(dentry))
error = -EBUSY;
if (!error) {
error = dir->i_op->unlink(dir, dentry);
if (!error)
- dentry->d_inode->i_flags |= S_DEAD;
+ dont_mount(dentry);
}
}
mutex_unlock(&dentry->d_inode->i_mutex);
if (error)
return error;
- vfs_dq_init(dir);
error = dir->i_op->symlink(dir, dentry, oldname);
if (!error)
fsnotify_create(dir, dentry);
return error;
mutex_lock(&inode->i_mutex);
- vfs_dq_init(dir);
error = dir->i_op->link(old_dentry, dir, new_dentry);
mutex_unlock(&inode->i_mutex);
if (!error)
* e) conversion from fhandle to dentry may come in the wrong moment - when
* we are removing the target. Solution: we will have to grab ->i_mutex
* in the fhandle_to_dentry code. [FIXME - current nfsfh.c relies on
- * ->i_mutex on parents, which works but leads to some truely excessive
+ * ->i_mutex on parents, which works but leads to some truly excessive
* locking].
*/
static int vfs_rename_dir(struct inode *old_dir, struct dentry *old_dentry,
return error;
target = new_dentry->d_inode;
- if (target) {
+ if (target)
mutex_lock(&target->i_mutex);
- dentry_unhash(new_dentry);
- }
if (d_mountpoint(old_dentry)||d_mountpoint(new_dentry))
error = -EBUSY;
- else
+ else {
+ if (target)
+ dentry_unhash(new_dentry);
error = old_dir->i_op->rename(old_dir, old_dentry, new_dir, new_dentry);
+ }
if (target) {
- if (!error)
+ if (!error) {
target->i_flags |= S_DEAD;
+ dont_mount(new_dentry);
+ }
mutex_unlock(&target->i_mutex);
if (d_unhashed(new_dentry))
d_rehash(new_dentry);
error = old_dir->i_op->rename(old_dir, old_dentry, new_dir, new_dentry);
if (!error) {
if (target)
- target->i_flags |= S_DEAD;
+ dont_mount(new_dentry);
if (!(old_dir->i_sb->s_type->fs_flags & FS_RENAME_DOES_D_MOVE))
d_move(old_dentry, new_dentry);
}
if (!old_dir->i_op->rename)
return -EPERM;
- vfs_dq_init(old_dir);
- vfs_dq_init(new_dir);
-
old_name = fsnotify_oldname_init(old_dentry->d_name.name);
if (is_dir)
Code Review / linux-2.6.git / blobdiff