#include <linux/file.h>
#include <linux/fcntl.h>
#include <linux/device_cgroup.h>
-#include <asm/namei.h>
#include <asm/uaccess.h>
#define ACC_MODE(x) ("\000\004\002\006"[(x)&O_ACCMODE])
{
umode_t mode = inode->i_mode;
+ mask &= MAY_READ | MAY_WRITE | MAY_EXEC;
+
if (current->fsuid == inode->i_uid)
mode >>= 6;
else {
/*
* If the DACs are ok we don't need any capability check.
*/
- if (((mode & mask & (MAY_READ|MAY_WRITE|MAY_EXEC)) == mask))
+ if ((mask & ~mode) == 0)
return 0;
check_capabilities:
int permission(struct inode *inode, int mask, struct nameidata *nd)
{
- int retval, submask;
+ int retval;
struct vfsmount *mnt = NULL;
if (nd)
}
/* Ordinary permission routines do not understand MAY_APPEND. */
- submask = mask & ~MAY_APPEND;
if (inode->i_op && inode->i_op->permission) {
- retval = inode->i_op->permission(inode, submask, nd);
+ int extra = 0;
+ if (nd) {
+ if (nd->flags & LOOKUP_OPEN)
+ extra |= MAY_OPEN;
+ }
+ retval = inode->i_op->permission(inode, mask | extra);
if (!retval) {
/*
* Exec permission on a regular file is denied if none
return -EACCES;
}
} else {
- retval = generic_permission(inode, submask, NULL);
+ retval = generic_permission(inode, mask, NULL);
}
if (retval)
return retval;
if (retval)
return retval;
- return security_inode_permission(inode, mask, nd);
+ return security_inode_permission(inode,
+ mask & (MAY_READ|MAY_WRITE|MAY_EXEC), nd);
}
/**
*/
result = d_lookup(parent, name);
if (!result) {
- struct dentry * dentry = d_alloc(parent, name);
+ struct dentry *dentry;
+
+ /* Don't create child dentry for a dead directory. */
+ result = ERR_PTR(-ENOENT);
+ if (IS_DEADDIR(dir))
+ goto out_unlock;
+
+ dentry = d_alloc(parent, name);
result = ERR_PTR(-ENOMEM);
if (dentry) {
result = dir->i_op->lookup(dir, dentry, nd);
else
result = dentry;
}
+out_unlock:
mutex_unlock(&dir->i_mutex);
return result;
}
return result;
}
-static int __emul_lookup_dentry(const char *, struct nameidata *);
-
/* SMP-safe */
-static __always_inline int
+static __always_inline void
walk_init_root(const char *name, struct nameidata *nd)
{
struct fs_struct *fs = current->fs;
read_lock(&fs->lock);
- if (fs->altroot.dentry && !(nd->flags & LOOKUP_NOALT)) {
- nd->path = fs->altroot;
- path_get(&fs->altroot);
- read_unlock(&fs->lock);
- if (__emul_lookup_dentry(name,nd))
- return 0;
- read_lock(&fs->lock);
- }
nd->path = fs->root;
path_get(&fs->root);
read_unlock(&fs->lock);
- return 1;
}
/*
if (*link == '/') {
path_put(&nd->path);
- if (!walk_init_root(link, nd))
- /* weird __emul_prefix() stuff did it */
- goto out;
+ walk_init_root(link, nd);
}
res = link_path_walk(link, nd);
-out:
if (nd->depth || res || nd->last_type!=LAST_NORM)
return res;
/*
return link_path_walk(name, nd);
}
-/*
- * SMP-safe: Returns 1 and nd will have valid dentry and mnt, if
- * everything is done. Returns 0 and drops input nd, if lookup failed;
- */
-static int __emul_lookup_dentry(const char *name, struct nameidata *nd)
-{
- if (path_walk(name, nd))
- return 0; /* something went wrong... */
-
- if (!nd->path.dentry->d_inode ||
- S_ISDIR(nd->path.dentry->d_inode->i_mode)) {
- struct path old_path = nd->path;
- struct qstr last = nd->last;
- int last_type = nd->last_type;
- struct fs_struct *fs = current->fs;
-
- /*
- * NAME was not found in alternate root or it's a directory.
- * Try to find it in the normal root:
- */
- nd->last_type = LAST_ROOT;
- read_lock(&fs->lock);
- nd->path = fs->root;
- path_get(&fs->root);
- read_unlock(&fs->lock);
- if (path_walk(name, nd) == 0) {
- if (nd->path.dentry->d_inode) {
- path_put(&old_path);
- return 1;
- }
- path_put(&nd->path);
- }
- nd->path = old_path;
- nd->last = last;
- nd->last_type = last_type;
- }
- return 1;
-}
-
-void set_fs_altroot(void)
-{
- char *emul = __emul_prefix();
- struct nameidata nd;
- struct path path = {}, old_path;
- int err;
- struct fs_struct *fs = current->fs;
-
- if (!emul)
- goto set_it;
- err = path_lookup(emul, LOOKUP_FOLLOW|LOOKUP_DIRECTORY|LOOKUP_NOALT, &nd);
- if (!err)
- path = nd.path;
-set_it:
- write_lock(&fs->lock);
- old_path = fs->altroot;
- fs->altroot = path;
- write_unlock(&fs->lock);
- if (old_path.dentry)
- path_put(&old_path);
-}
-
/* Returns 0 and nd will be valid on success; Retuns error, otherwise. */
static int do_path_lookup(int dfd, const char *name,
unsigned int flags, struct nameidata *nd)
if (*name=='/') {
read_lock(&fs->lock);
- if (fs->altroot.dentry && !(nd->flags & LOOKUP_NOALT)) {
- nd->path = fs->altroot;
- path_get(&fs->altroot);
- read_unlock(&fs->lock);
- if (__emul_lookup_dentry(name,nd))
- goto out; /* found in altroot */
- read_lock(&fs->lock);
- }
nd->path = fs->root;
path_get(&fs->root);
read_unlock(&fs->lock);
}
retval = path_walk(name, nd);
-out:
if (unlikely(!retval && !audit_dummy_context() && nd->path.dentry &&
nd->path.dentry->d_inode))
audit_inode(name, nd->path.dentry);
dentry = cached_lookup(base, name, nd);
if (!dentry) {
- struct dentry *new = d_alloc(base, name);
+ struct dentry *new;
+
+ /* Don't create child dentry for a dead directory. */
+ dentry = ERR_PTR(-ENOENT);
+ if (IS_DEADDIR(inode))
+ goto out;
+
+ new = d_alloc(base, name);
dentry = ERR_PTR(-ENOMEM);
if (!new)
goto out;
return do_unlinkat(AT_FDCWD, pathname);
}
-int vfs_symlink(struct inode *dir, struct dentry *dentry, const char *oldname, int mode)
+int vfs_symlink(struct inode *dir, struct dentry *dentry, const char *oldname)
{
int error = may_create(dir, dentry, NULL);
error = mnt_want_write(nd.path.mnt);
if (error)
goto out_dput;
- error = vfs_symlink(nd.path.dentry->d_inode, dentry, from, S_IALLUGO);
+ error = vfs_symlink(nd.path.dentry->d_inode, dentry, from);
mnt_drop_write(nd.path.mnt);
out_dput:
dput(dentry);
return -EPERM;
if (!dir->i_op || !dir->i_op->link)
return -EPERM;
- if (S_ISDIR(old_dentry->d_inode->i_mode))
+ if (S_ISDIR(inode->i_mode))
return -EPERM;
error = security_inode_link(old_dentry, dir, new_dentry);
if (error)
return error;
- mutex_lock(&old_dentry->d_inode->i_mutex);
+ mutex_lock(&inode->i_mutex);
DQUOT_INIT(dir);
error = dir->i_op->link(old_dentry, dir, new_dentry);
- mutex_unlock(&old_dentry->d_inode->i_mutex);
+ mutex_unlock(&inode->i_mutex);
if (!error)
- fsnotify_link(dir, old_dentry->d_inode, new_dentry);
+ fsnotify_link(dir, inode, new_dentry);
return error;
}