* Read/write DACs are always overridable.
* Executable DACs are overridable if at least one exec bit is set.
*/
- if (!(mask & MAY_EXEC) ||
- (inode->i_mode & S_IXUGO) || S_ISDIR(inode->i_mode))
+ if (!(mask & MAY_EXEC) || execute_ok(inode))
if (capable(CAP_DAC_OVERRIDE))
return 0;
}
/* Ordinary permission routines do not understand MAY_APPEND. */
- if (inode->i_op && inode->i_op->permission) {
+ if (inode->i_op && inode->i_op->permission)
retval = inode->i_op->permission(inode, mask);
- if (!retval) {
- /*
- * Exec permission on a regular file is denied if none
- * of the execute bits are set.
- *
- * This check should be done by the ->permission()
- * method.
- */
- if ((mask & MAY_EXEC) && S_ISREG(inode->i_mode) &&
- !(inode->i_mode & S_IXUGO))
- return -EACCES;
- }
- } else {
+ else
retval = generic_permission(inode, mask, NULL);
- }
+
if (retval)
return retval;
return retval;
return security_inode_permission(inode,
- mask & (MAY_READ|MAY_WRITE|MAY_EXEC));
+ mask & (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND));
}
/**
return do_path_lookup(AT_FDCWD, name, flags, nd);
}
+int kern_path(const char *name, unsigned int flags, struct path *path)
+{
+ struct nameidata nd;
+ int res = do_path_lookup(AT_FDCWD, name, flags, &nd);
+ if (!res)
+ *path = nd.path;
+ return res;
+}
+
/**
* vfs_path_lookup - lookup a file path relative to a dentry-vfsmount pair
* @dentry: pointer to dentry of the base directory
}
-static int __path_lookup_intent_open(int dfd, const char *name,
- unsigned int lookup_flags, struct nameidata *nd,
- int open_flags, int create_mode)
+/**
+ * path_lookup_open - lookup a file path with open intent
+ * @dfd: the directory to use as base, or AT_FDCWD
+ * @name: pointer to file name
+ * @lookup_flags: lookup intent flags
+ * @nd: pointer to nameidata
+ * @open_flags: open intent flags
+ */
+int path_lookup_open(int dfd, const char *name, unsigned int lookup_flags,
+ struct nameidata *nd, int open_flags)
{
struct file *filp = get_empty_filp();
int err;
return -ENFILE;
nd->intent.open.file = filp;
nd->intent.open.flags = open_flags;
- nd->intent.open.create_mode = create_mode;
+ nd->intent.open.create_mode = 0;
err = do_path_lookup(dfd, name, lookup_flags|LOOKUP_OPEN, nd);
if (IS_ERR(nd->intent.open.file)) {
if (err == 0) {
return err;
}
-/**
- * path_lookup_open - lookup a file path with open intent
- * @dfd: the directory to use as base, or AT_FDCWD
- * @name: pointer to file name
- * @lookup_flags: lookup intent flags
- * @nd: pointer to nameidata
- * @open_flags: open intent flags
- */
-int path_lookup_open(int dfd, const char *name, unsigned int lookup_flags,
- struct nameidata *nd, int open_flags)
-{
- return __path_lookup_intent_open(dfd, name, lookup_flags, nd,
- open_flags, 0);
-}
-
-/**
- * path_lookup_create - lookup a file path with open + create intent
- * @dfd: the directory to use as base, or AT_FDCWD
- * @name: pointer to file name
- * @lookup_flags: lookup intent flags
- * @nd: pointer to nameidata
- * @open_flags: open intent flags
- * @create_mode: create intent flags
- */
-static int path_lookup_create(int dfd, const char *name,
- unsigned int lookup_flags, struct nameidata *nd,
- int open_flags, int create_mode)
-{
- return __path_lookup_intent_open(dfd, name, lookup_flags|LOOKUP_CREATE,
- nd, open_flags, create_mode);
-}
-
static struct dentry *__lookup_hash(struct qstr *name,
struct dentry *base, struct nameidata *nd)
{
if (IS_APPEND(dir))
return -EPERM;
if (check_sticky(dir, victim->d_inode)||IS_APPEND(victim->d_inode)||
- IS_IMMUTABLE(victim->d_inode))
+ IS_IMMUTABLE(victim->d_inode) || IS_SWAPFILE(victim->d_inode))
return -EPERM;
if (isdir) {
if (!S_ISDIR(victim->d_inode->i_mode))
* 3. We should have write and exec permissions on dir
* 4. We can't do it if dir is immutable (done in permission())
*/
-static inline int may_create(struct inode *dir, struct dentry *child,
- struct nameidata *nd)
+static inline int may_create(struct inode *dir, struct dentry *child)
{
if (child->d_inode)
return -EEXIST;
mutex_lock(&p1->d_inode->i_sb->s_vfs_rename_mutex);
- for (p = p1; p->d_parent != p; p = p->d_parent) {
- if (p->d_parent == p2) {
- mutex_lock_nested(&p2->d_inode->i_mutex, I_MUTEX_PARENT);
- mutex_lock_nested(&p1->d_inode->i_mutex, I_MUTEX_CHILD);
- return p;
- }
+ p = d_ancestor(p2, p1);
+ if (p) {
+ mutex_lock_nested(&p2->d_inode->i_mutex, I_MUTEX_PARENT);
+ mutex_lock_nested(&p1->d_inode->i_mutex, I_MUTEX_CHILD);
+ return p;
}
- for (p = p2; p->d_parent != p; p = p->d_parent) {
- if (p->d_parent == p1) {
- mutex_lock_nested(&p1->d_inode->i_mutex, I_MUTEX_PARENT);
- mutex_lock_nested(&p2->d_inode->i_mutex, I_MUTEX_CHILD);
- return p;
- }
+ p = d_ancestor(p1, p2);
+ if (p) {
+ mutex_lock_nested(&p1->d_inode->i_mutex, I_MUTEX_PARENT);
+ mutex_lock_nested(&p2->d_inode->i_mutex, I_MUTEX_CHILD);
+ return p;
}
mutex_lock_nested(&p1->d_inode->i_mutex, I_MUTEX_PARENT);
int vfs_create(struct inode *dir, struct dentry *dentry, int mode,
struct nameidata *nd)
{
- int error = may_create(dir, dentry, nd);
+ int error = may_create(dir, dentry);
if (error)
return error;
/*
* Create - we need to know the parent.
*/
- error = path_lookup_create(dfd, pathname, LOOKUP_PARENT,
- &nd, flag, mode);
+ error = do_path_lookup(dfd, pathname, LOOKUP_PARENT, &nd);
if (error)
return ERR_PTR(error);
*/
error = -EISDIR;
if (nd.last_type != LAST_NORM || nd.last.name[nd.last.len])
- goto exit;
+ goto exit_parent;
+ error = -ENFILE;
+ filp = get_empty_filp();
+ if (filp == NULL)
+ goto exit_parent;
+ nd.intent.open.file = filp;
+ 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;
exit:
if (!IS_ERR(nd.intent.open.file))
release_open_intent(&nd);
+exit_parent:
path_put(&nd.path);
return ERR_PTR(error);
if (nd->last_type != LAST_NORM)
goto fail;
nd->flags &= ~LOOKUP_PARENT;
- nd->flags |= LOOKUP_CREATE;
+ nd->flags |= LOOKUP_CREATE | LOOKUP_EXCL;
nd->intent.open.flags = O_EXCL;
/*
int vfs_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t dev)
{
- int error = may_create(dir, dentry, NULL);
+ int error = may_create(dir, dentry);
if (error)
return error;
int vfs_mkdir(struct inode *dir, struct dentry *dentry, int mode)
{
- int error = may_create(dir, dentry, NULL);
+ int error = may_create(dir, dentry);
if (error)
return error;
return error;
switch(nd.last_type) {
- case LAST_DOTDOT:
- error = -ENOTEMPTY;
- goto exit1;
- case LAST_DOT:
- error = -EINVAL;
- goto exit1;
- case LAST_ROOT:
- error = -EBUSY;
- goto exit1;
+ case LAST_DOTDOT:
+ error = -ENOTEMPTY;
+ goto exit1;
+ case LAST_DOT:
+ error = -EINVAL;
+ goto exit1;
+ case LAST_ROOT:
+ error = -EBUSY;
+ goto exit1;
}
+
+ nd.flags &= ~LOOKUP_PARENT;
+
mutex_lock_nested(&nd.path.dentry->d_inode->i_mutex, I_MUTEX_PARENT);
dentry = lookup_hash(&nd);
error = PTR_ERR(dentry);
error = -EISDIR;
if (nd.last_type != LAST_NORM)
goto exit1;
+
+ nd.flags &= ~LOOKUP_PARENT;
+
mutex_lock_nested(&nd.path.dentry->d_inode->i_mutex, I_MUTEX_PARENT);
dentry = lookup_hash(&nd);
error = PTR_ERR(dentry);
int vfs_symlink(struct inode *dir, struct dentry *dentry, const char *oldname)
{
- int error = may_create(dir, dentry, NULL);
+ int error = may_create(dir, dentry);
if (error)
return error;
if (!inode)
return -ENOENT;
- error = may_create(dir, new_dentry, NULL);
+ error = may_create(dir, new_dentry);
if (error)
return error;
return error;
if (!new_dentry->d_inode)
- error = may_create(new_dir, new_dentry, NULL);
+ error = may_create(new_dir, new_dentry);
else
error = may_delete(new_dir, new_dentry, is_dir);
if (error)
if (newnd.last_type != LAST_NORM)
goto exit2;
+ oldnd.flags &= ~LOOKUP_PARENT;
+ newnd.flags &= ~LOOKUP_PARENT;
+ newnd.flags |= LOOKUP_RENAME_TARGET;
+
trap = lock_rename(new_dir, old_dir);
old_dentry = lookup_hash(&oldnd);
EXPORT_SYMBOL(page_symlink);
EXPORT_SYMBOL(page_symlink_inode_operations);
EXPORT_SYMBOL(path_lookup);
+EXPORT_SYMBOL(kern_path);
EXPORT_SYMBOL(vfs_path_lookup);
EXPORT_SYMBOL(inode_permission);
EXPORT_SYMBOL(vfs_permission);