1 files changed, 118 insertions, 236 deletions

diff --git a/fs/namei.c b/fs/namei.c
index 01e67dddcc3d..a7b0a0b80128 100644
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -31,7 +31,6 @@
 #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])
@@ -185,6 +184,8 @@ int generic_permission(struct inode *inode, int mask,
 {
         umode_t                 mode = inode->i_mode;
 
+        mask &= MAY_READ | MAY_WRITE | MAY_EXEC;
+
         if (current->fsuid == inode->i_uid)
                 mode >>= 6;
         else {
@@ -203,7 +204,7 @@ int generic_permission(struct inode *inode, int mask,
         /*
          * 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:
@@ -226,13 +227,9 @@ int generic_permission(struct inode *inode, int mask,
         return -EACCES;
 }
 
-int permission(struct inode *inode, int mask, struct nameidata *nd)
+int inode_permission(struct inode *inode, int mask)
 {
-        int retval, submask;
-        struct vfsmount *mnt = NULL;
-
-        if (nd)
-                mnt = nd->path.mnt;
+        int retval;
 
         if (mask & MAY_WRITE) {
                 umode_t mode = inode->i_mode;
@@ -251,19 +248,9 @@ int permission(struct inode *inode, int mask, struct nameidata *nd)
                         return -EACCES;
         }
 
-        if ((mask & MAY_EXEC) && S_ISREG(inode->i_mode)) {
-                /*
-                 * MAY_EXEC on regular files is denied if the fs is mounted
-                 * with the "noexec" flag.
-                 */
-                if (mnt && (mnt->mnt_flags & MNT_NOEXEC))
-                        return -EACCES;
-        }
-
         /* 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);
+                retval = inode->i_op->permission(inode, mask);
                 if (!retval) {
                         /*
                          * Exec permission on a regular file is denied if none
@@ -277,7 +264,7 @@ int permission(struct inode *inode, int mask, struct nameidata *nd)
                                 return -EACCES;
                 }
         } else {
-                retval = generic_permission(inode, submask, NULL);
+                retval = generic_permission(inode, mask, NULL);
         }
         if (retval)
                 return retval;
@@ -286,7 +273,8 @@ int permission(struct inode *inode, int mask, struct nameidata *nd)
         if (retval)
                 return retval;
 
-        return security_inode_permission(inode, mask, nd);
+        return security_inode_permission(inode,
+                        mask & (MAY_READ|MAY_WRITE|MAY_EXEC));
 }
 
 /**
@@ -301,7 +289,7 @@ int permission(struct inode *inode, int mask, struct nameidata *nd)
  */
 int vfs_permission(struct nameidata *nd, int mask)
 {
-        return permission(nd->path.dentry->d_inode, mask, nd);
+        return inode_permission(nd->path.dentry->d_inode, mask);
 }
 
 /**
@@ -318,7 +306,7 @@ int vfs_permission(struct nameidata *nd, int mask)
  */
 int file_permission(struct file *file, int mask)
 {
-        return permission(file->f_path.dentry->d_inode, mask, NULL);
+        return inode_permission(file->f_path.dentry->d_inode, mask);
 }
 
 /*
@@ -459,8 +447,7 @@ static struct dentry * cached_lookup(struct dentry * parent, struct qstr * name,
  * short-cut DAC fails, then call permission() to do more
  * complete permission check.
  */
-static int exec_permission_lite(struct inode *inode,
-                                       struct nameidata *nd)
+static int exec_permission_lite(struct inode *inode)
 {
         umode_t mode = inode->i_mode;
 
@@ -486,7 +473,7 @@ static int exec_permission_lite(struct inode *inode,
 
         return -EACCES;
 ok:
-        return security_inode_permission(inode, MAY_EXEC, nd);
+        return security_inode_permission(inode, MAY_EXEC);
 }
 
 /*
@@ -519,7 +506,14 @@ static struct dentry * real_lookup(struct dentry * parent, struct qstr * name, s
          */
         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);
@@ -528,6 +522,7 @@ static struct dentry * real_lookup(struct dentry * parent, struct qstr * name, s
                         else
                                 result = dentry;
                 }
+out_unlock:
                 mutex_unlock(&dir->i_mutex);
                 return result;
         }
@@ -545,27 +540,16 @@ static struct dentry * real_lookup(struct dentry * parent, struct qstr * name, s
         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;
 }
 
 /*
@@ -606,12 +590,9 @@ static __always_inline int __vfs_follow_link(struct nameidata *nd, const char *l
 
         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;
         /*
@@ -889,7 +870,7 @@ static int __link_path_walk(const char *name, struct nameidata *nd)
                 unsigned int c;
 
                 nd->flags |= LOOKUP_CONTINUE;
-                err = exec_permission_lite(inode, nd);
+                err = exec_permission_lite(inode);
                 if (err == -EAGAIN)
                         err = vfs_permission(nd, MAY_EXEC);
                 if (err)
@@ -1060,67 +1041,6 @@ static int path_walk(const char *name, struct nameidata *nd)
         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)
@@ -1136,14 +1056,6 @@ static int do_path_lookup(int dfd, const char *name,
 
         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);
@@ -1177,7 +1089,6 @@ static int do_path_lookup(int dfd, const char *name,
         }
 
         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);
@@ -1282,19 +1193,6 @@ static int path_lookup_create(int dfd, const char *name,
                         nd, open_flags, create_mode);
 }
 
-int __user_path_lookup_open(const char __user *name, unsigned int lookup_flags,
-                struct nameidata *nd, int open_flags)
-{
-        char *tmp = getname(name);
-        int err = PTR_ERR(tmp);
-
-        if (!IS_ERR(tmp)) {
-                err = __path_lookup_intent_open(AT_FDCWD, tmp, lookup_flags, nd, open_flags, 0);
-                putname(tmp);
-        }
-        return err;
-}
-
 static struct dentry *__lookup_hash(struct qstr *name,
                 struct dentry *base, struct nameidata *nd)
 {
@@ -1317,7 +1215,14 @@ static struct dentry *__lookup_hash(struct qstr *name,
 
         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;
@@ -1340,7 +1245,7 @@ static struct dentry *lookup_hash(struct nameidata *nd)
 {
         int err;
 
-        err = permission(nd->path.dentry->d_inode, MAY_EXEC, nd);
+        err = inode_permission(nd->path.dentry->d_inode, MAY_EXEC);
         if (err)
                 return ERR_PTR(err);
         return __lookup_hash(&nd->last, nd->path.dentry, nd);
@@ -1388,7 +1293,7 @@ struct dentry *lookup_one_len(const char *name, struct dentry *base, int len)
         if (err)
                 return ERR_PTR(err);
 
-        err = permission(base->d_inode, MAY_EXEC, NULL);
+        err = inode_permission(base->d_inode, MAY_EXEC);
         if (err)
                 return ERR_PTR(err);
         return __lookup_hash(&this, base, NULL);
@@ -1416,22 +1321,40 @@ struct dentry *lookup_one_noperm(const char *name, struct dentry *base)
         return __lookup_hash(&this, base, NULL);
 }
 
-int __user_walk_fd(int dfd, const char __user *name, unsigned flags,
-                            struct nameidata *nd)
+int user_path_at(int dfd, const char __user *name, unsigned flags,
+                 struct path *path)
 {
+        struct nameidata nd;
         char *tmp = getname(name);
         int err = PTR_ERR(tmp);
-
         if (!IS_ERR(tmp)) {
-                err = do_path_lookup(dfd, tmp, flags, nd);
+
+                BUG_ON(flags & LOOKUP_PARENT);
+
+                err = do_path_lookup(dfd, tmp, flags, &nd);
                 putname(tmp);
+                if (!err)
+                        *path = nd.path;
         }
         return err;
 }
 
-int __user_walk(const char __user *name, unsigned flags, struct nameidata *nd)
+static int user_path_parent(int dfd, const char __user *path,
+                        struct nameidata *nd, char **name)
 {
-        return __user_walk_fd(AT_FDCWD, name, flags, nd);
+        char *s = getname(path);
+        int error;
+
+        if (IS_ERR(s))
+                return PTR_ERR(s);
+
+        error = do_path_lookup(dfd, s, LOOKUP_PARENT, nd);
+        if (error)
+                putname(s);
+        else
+                *name = s;
+
+        return error;
 }
 
 /*
@@ -1478,7 +1401,7 @@ static int may_delete(struct inode *dir,struct dentry *victim,int isdir)
         BUG_ON(victim->d_parent->d_inode != dir);
         audit_inode_child(victim->d_name.name, victim, dir);
 
-        error = permission(dir,MAY_WRITE | MAY_EXEC, NULL);
+        error = inode_permission(dir, MAY_WRITE | MAY_EXEC);
         if (error)
                 return error;
         if (IS_APPEND(dir))
@@ -1515,7 +1438,7 @@ static inline int may_create(struct inode *dir, struct dentry *child,
                 return -EEXIST;
         if (IS_DEADDIR(dir))
                 return -ENOENT;
-        return permission(dir,MAY_WRITE | MAY_EXEC, nd);
+        return inode_permission(dir, MAY_WRITE | MAY_EXEC);
 }
 
 /* 
@@ -1755,7 +1678,7 @@ struct file *do_filp_open(int dfd, const char *pathname,
         int will_write;
         int flag = open_to_namei_flags(open_flag);
 
-        acc_mode = ACC_MODE(flag);
+        acc_mode = MAY_OPEN | ACC_MODE(flag);
 
         /* O_TRUNC implies we need access checks for write permissions */
         if (flag & O_TRUNC)
@@ -2071,20 +1994,18 @@ static int may_mknod(mode_t mode)
 asmlinkage long sys_mknodat(int dfd, const char __user *filename, int mode,
                                 unsigned dev)
 {
-        int error = 0;
-        char * tmp;
-        struct dentry * dentry;
+        int error;
+        char *tmp;
+        struct dentry *dentry;
         struct nameidata nd;
 
         if (S_ISDIR(mode))
                 return -EPERM;
-        tmp = getname(filename);
-        if (IS_ERR(tmp))
-                return PTR_ERR(tmp);
 
-        error = do_path_lookup(dfd, tmp, LOOKUP_PARENT, &nd);
+        error = user_path_parent(dfd, filename, &nd, &tmp);
         if (error)
-                goto out;
+                return error;
+
         dentry = lookup_create(&nd, 0);
         if (IS_ERR(dentry)) {
                 error = PTR_ERR(dentry);
@@ -2116,7 +2037,6 @@ out_dput:
 out_unlock:
         mutex_unlock(&nd.path.dentry->d_inode->i_mutex);
         path_put(&nd.path);
-out:
         putname(tmp);
 
         return error;
@@ -2156,14 +2076,10 @@ asmlinkage long sys_mkdirat(int dfd, const char __user *pathname, int mode)
         struct dentry *dentry;
         struct nameidata nd;
 
-        tmp = getname(pathname);
-        error = PTR_ERR(tmp);
-        if (IS_ERR(tmp))
+        error = user_path_parent(dfd, pathname, &nd, &tmp);
+        if (error)
                 goto out_err;
 
-        error = do_path_lookup(dfd, tmp, LOOKUP_PARENT, &nd);
-        if (error)
-                goto out;
         dentry = lookup_create(&nd, 1);
         error = PTR_ERR(dentry);
         if (IS_ERR(dentry))
@@ -2181,7 +2097,6 @@ out_dput:
 out_unlock:
         mutex_unlock(&nd.path.dentry->d_inode->i_mutex);
         path_put(&nd.path);
-out:
         putname(tmp);
 out_err:
         return error;
@@ -2259,13 +2174,9 @@ static long do_rmdir(int dfd, const char __user *pathname)
         struct dentry *dentry;
         struct nameidata nd;
 
-        name = getname(pathname);
-        if(IS_ERR(name))
-                return PTR_ERR(name);
-
-        error = do_path_lookup(dfd, name, LOOKUP_PARENT, &nd);
+        error = user_path_parent(dfd, pathname, &nd, &name);
         if (error)
-                goto exit;
+                return error;
 
         switch(nd.last_type) {
                 case LAST_DOTDOT:
@@ -2294,7 +2205,6 @@ exit2:
         mutex_unlock(&nd.path.dentry->d_inode->i_mutex);
 exit1:
         path_put(&nd.path);
-exit:
         putname(name);
         return error;
 }
@@ -2343,19 +2253,16 @@ int vfs_unlink(struct inode *dir, struct dentry *dentry)
  */
 static long do_unlinkat(int dfd, const char __user *pathname)
 {
-        int error = 0;
-        char * name;
+        int error;
+        char *name;
         struct dentry *dentry;
         struct nameidata nd;
         struct inode *inode = NULL;
 
-        name = getname(pathname);
-        if(IS_ERR(name))
-                return PTR_ERR(name);
-
-        error = do_path_lookup(dfd, name, LOOKUP_PARENT, &nd);
+        error = user_path_parent(dfd, pathname, &nd, &name);
         if (error)
-                goto exit;
+                return error;
+
         error = -EISDIR;
         if (nd.last_type != LAST_NORM)
                 goto exit1;
@@ -2382,7 +2289,6 @@ static long do_unlinkat(int dfd, const char __user *pathname)
                 iput(inode);    /* truncate the inode here */
 exit1:
         path_put(&nd.path);
-exit:
         putname(name);
         return error;
 
@@ -2408,7 +2314,7 @@ asmlinkage long sys_unlink(const char __user *pathname)
         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);
 
@@ -2432,23 +2338,20 @@ int vfs_symlink(struct inode *dir, struct dentry *dentry, const char *oldname, i
 asmlinkage long sys_symlinkat(const char __user *oldname,
                               int newdfd, const char __user *newname)
 {
-        int error = 0;
-        char * from;
-        char * to;
+        int error;
+        char *from;
+        char *to;
         struct dentry *dentry;
         struct nameidata nd;
 
         from = getname(oldname);
-        if(IS_ERR(from))
+        if (IS_ERR(from))
                 return PTR_ERR(from);
-        to = getname(newname);
-        error = PTR_ERR(to);
-        if (IS_ERR(to))
-                goto out_putname;
 
-        error = do_path_lookup(newdfd, to, LOOKUP_PARENT, &nd);
+        error = user_path_parent(newdfd, newname, &nd, &to);
         if (error)
-                goto out;
+                goto out_putname;
+
         dentry = lookup_create(&nd, 0);
         error = PTR_ERR(dentry);
         if (IS_ERR(dentry))
@@ -2457,14 +2360,13 @@ asmlinkage long sys_symlinkat(const char __user *oldname,
         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);
 out_unlock:
         mutex_unlock(&nd.path.dentry->d_inode->i_mutex);
         path_put(&nd.path);
-out:
         putname(to);
 out_putname:
         putname(from);
@@ -2498,19 +2400,19 @@ int vfs_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_de
                 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;
 }
 
@@ -2528,27 +2430,25 @@ asmlinkage long sys_linkat(int olddfd, const char __user *oldname,
                            int flags)
 {
         struct dentry *new_dentry;
-        struct nameidata nd, old_nd;
+        struct nameidata nd;
+        struct path old_path;
         int error;
-        char * to;
+        char *to;
 
         if ((flags & ~AT_SYMLINK_FOLLOW) != 0)
                 return -EINVAL;
 
-        to = getname(newname);
-        if (IS_ERR(to))
-                return PTR_ERR(to);
-
-        error = __user_walk_fd(olddfd, oldname,
-                               flags & AT_SYMLINK_FOLLOW ? LOOKUP_FOLLOW : 0,
-                               &old_nd);
+        error = user_path_at(olddfd, oldname,
+                             flags & AT_SYMLINK_FOLLOW ? LOOKUP_FOLLOW : 0,
+                             &old_path);
         if (error)
-                goto exit;
-        error = do_path_lookup(newdfd, to, LOOKUP_PARENT, &nd);
+                return error;
+
+        error = user_path_parent(newdfd, newname, &nd, &to);
         if (error)
                 goto out;
         error = -EXDEV;
-        if (old_nd.path.mnt != nd.path.mnt)
+        if (old_path.mnt != nd.path.mnt)
                 goto out_release;
         new_dentry = lookup_create(&nd, 0);
         error = PTR_ERR(new_dentry);
@@ -2557,7 +2457,7 @@ asmlinkage long sys_linkat(int olddfd, const char __user *oldname,
         error = mnt_want_write(nd.path.mnt);
         if (error)
                 goto out_dput;
-        error = vfs_link(old_nd.path.dentry, nd.path.dentry->d_inode, new_dentry);
+        error = vfs_link(old_path.dentry, nd.path.dentry->d_inode, new_dentry);
         mnt_drop_write(nd.path.mnt);
 out_dput:
         dput(new_dentry);
@@ -2565,10 +2465,9 @@ out_unlock:
         mutex_unlock(&nd.path.dentry->d_inode->i_mutex);
 out_release:
         path_put(&nd.path);
-out:
-        path_put(&old_nd.path);
-exit:
         putname(to);
+out:
+        path_put(&old_path);
 
         return error;
 }
@@ -2621,7 +2520,7 @@ static int vfs_rename_dir(struct inode *old_dir, struct dentry *old_dentry,
          * we'll need to flip '..'.
          */
         if (new_dir != old_dir) {
-                error = permission(old_dentry->d_inode, MAY_WRITE, NULL);
+                error = inode_permission(old_dentry->d_inode, MAY_WRITE);
                 if (error)
                         return error;
         }
@@ -2724,20 +2623,22 @@ int vfs_rename(struct inode *old_dir, struct dentry *old_dentry,
         return error;
 }
 
-static int do_rename(int olddfd, const char *oldname,
-                        int newdfd, const char *newname)
+asmlinkage long sys_renameat(int olddfd, const char __user *oldname,
+                             int newdfd, const char __user *newname)
 {
-        int error = 0;
-        struct dentry * old_dir, * new_dir;
-        struct dentry * old_dentry, *new_dentry;
-        struct dentry * trap;
+        struct dentry *old_dir, *new_dir;
+        struct dentry *old_dentry, *new_dentry;
+        struct dentry *trap;
         struct nameidata oldnd, newnd;
+        char *from;
+        char *to;
+        int error;
 
-        error = do_path_lookup(olddfd, oldname, LOOKUP_PARENT, &oldnd);
+        error = user_path_parent(olddfd, oldname, &oldnd, &from);
         if (error)
                 goto exit;
 
-        error = do_path_lookup(newdfd, newname, LOOKUP_PARENT, &newnd);
+        error = user_path_parent(newdfd, newname, &newnd, &to);
         if (error)
                 goto exit1;
 
@@ -2799,29 +2700,11 @@ exit3:
         unlock_rename(new_dir, old_dir);
 exit2:
         path_put(&newnd.path);
+        putname(to);
 exit1:
         path_put(&oldnd.path);
-exit:
-        return error;
-}
-
-asmlinkage long sys_renameat(int olddfd, const char __user *oldname,
-                             int newdfd, const char __user *newname)
-{
-        int error;
-        char * from;
-        char * to;
-
-        from = getname(oldname);
-        if(IS_ERR(from))
-                return PTR_ERR(from);
-        to = getname(newname);
-        error = PTR_ERR(to);
-        if (!IS_ERR(to)) {
-                error = do_rename(olddfd, from, newdfd, to);
-                putname(to);
-        }
         putname(from);
+exit:
         return error;
 }
 
@@ -2959,8 +2842,7 @@ const struct inode_operations page_symlink_inode_operations = {
         .put_link       = page_put_link,
 };
 
-EXPORT_SYMBOL(__user_walk);
-EXPORT_SYMBOL(__user_walk_fd);
+EXPORT_SYMBOL(user_path_at);
 EXPORT_SYMBOL(follow_down);
 EXPORT_SYMBOL(follow_up);
 EXPORT_SYMBOL(get_write_access); /* binfmt_aout */
@@ -2975,7 +2857,7 @@ EXPORT_SYMBOL(page_symlink);
 EXPORT_SYMBOL(page_symlink_inode_operations);
 EXPORT_SYMBOL(path_lookup);
 EXPORT_SYMBOL(vfs_path_lookup);
-EXPORT_SYMBOL(permission);
+EXPORT_SYMBOL(inode_permission);
 EXPORT_SYMBOL(vfs_permission);
 EXPORT_SYMBOL(file_permission);
 EXPORT_SYMBOL(unlock_rename);