Merge branch 'work.namei' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

Pull vfs namei updates from Al Viro:
 "Pathwalk-related stuff"

[ Audit-related cleanups, misc simplifications, and easier to follow
  nd->root refcounts     - Linus ]

* 'work.namei' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  devpts_pty_kill(): don't bother with d_delete()
  infiniband: don't bother with d_delete()
  hypfs: don't bother with d_delete()
  fs/namei.c: keep track of nd->root refcount status
  fs/namei.c: new helper - legitimize_root()
  kill the last users of user_{path,lpath,path_dir}()
  namei.h: get the comments on LOOKUP_... in sync with reality
  kill LOOKUP_NO_EVAL, don't bother including namei.h from audit.h
  audit_inode(): switch to passing AUDIT_INODE_...
  filename_mountpoint(): make LOOKUP_NO_EVAL unconditional there
  filename_lookup(): audit_inode() argument is always 0

6 files changed, 37 insertions, 50 deletions

diff --git a/fs/coda/pioctl.c b/fs/coda/pioctl.c
index 644d48c12ce8..3aec27e5eb82 100644
--- a/fs/coda/pioctl.c
+++ b/fs/coda/pioctl.c
@@ -63,11 +63,8 @@ static long coda_pioctl(struct file *filp, unsigned int cmd,
 	 * Look up the pathname. Note that the pathname is in
 	 * user memory, and namei takes care of this
 	 */
-	if (data.follow)
-		error = user_path(data.path, &path);
-	else
-		error = user_lpath(data.path, &path);
-
+	error = user_path_at(AT_FDCWD, data.path,
+			     data.follow ? LOOKUP_FOLLOW : 0, &path);
 	if (error)
 		return error;
 
diff --git a/fs/devpts/inode.c b/fs/devpts/inode.c
index beeadca23b05..42e5a766d33c 100644
--- a/fs/devpts/inode.c
+++ b/fs/devpts/inode.c
@@ -622,7 +622,7 @@ void devpts_pty_kill(struct dentry *dentry)
 	dentry->d_fsdata = NULL;
 	drop_nlink(dentry->d_inode);
 	fsnotify_unlink(d_inode(dentry->d_parent), dentry);
-	d_delete(dentry);
+	d_drop(dentry);
 	dput(dentry);	/* d_alloc_name() in devpts_pty_new() */
 }
 
diff --git a/fs/namei.c b/fs/namei.c
index 209c51a5226c..671c3c1a3425 100644
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -596,14 +596,12 @@ static void terminate_walk(struct nameidata *nd)
 		path_put(&nd->path);
 		for (i = 0; i < nd->depth; i++)
 			path_put(&nd->stack[i].link);
-		if (nd->root.mnt && !(nd->flags & LOOKUP_ROOT)) {
+		if (nd->flags & LOOKUP_ROOT_GRABBED) {
 			path_put(&nd->root);
-			nd->root.mnt = NULL;
+			nd->flags &= ~LOOKUP_ROOT_GRABBED;
 		}
 	} else {
 		nd->flags &= ~LOOKUP_RCU;
-		if (!(nd->flags & LOOKUP_ROOT))
-			nd->root.mnt = NULL;
 		rcu_read_unlock();
 	}
 	nd->depth = 0;
@@ -641,6 +639,14 @@ static bool legitimize_links(struct nameidata *nd)
 	return true;
 }
 
+static bool legitimize_root(struct nameidata *nd)
+{
+	if (!nd->root.mnt || (nd->flags & LOOKUP_ROOT))
+		return true;
+	nd->flags |= LOOKUP_ROOT_GRABBED;
+	return legitimize_path(nd, &nd->root, nd->root_seq);
+}
+
 /*
  * Path walking has 2 modes, rcu-walk and ref-walk (see
  * Documentation/filesystems/path-lookup.txt).  In situations when we can't
@@ -671,23 +677,18 @@ static int unlazy_walk(struct nameidata *nd)
 
 	nd->flags &= ~LOOKUP_RCU;
 	if (unlikely(!legitimize_links(nd)))
-		goto out2;
-	if (unlikely(!legitimize_path(nd, &nd->path, nd->seq)))
 		goto out1;
-	if (nd->root.mnt && !(nd->flags & LOOKUP_ROOT)) {
-		if (unlikely(!legitimize_path(nd, &nd->root, nd->root_seq)))
-			goto out;
-	}
+	if (unlikely(!legitimize_path(nd, &nd->path, nd->seq)))
+		goto out;
+	if (unlikely(!legitimize_root(nd)))
+		goto out;
 	rcu_read_unlock();
 	BUG_ON(nd->inode != parent->d_inode);
 	return 0;
 
-out2:
+out1:
 	nd->path.mnt = NULL;
 	nd->path.dentry = NULL;
-out1:
-	if (!(nd->flags & LOOKUP_ROOT))
-		nd->root.mnt = NULL;
 out:
 	rcu_read_unlock();
 	return -ECHILD;
@@ -727,23 +728,14 @@ static int unlazy_child(struct nameidata *nd, struct dentry *dentry, unsigned se
 	 */
 	if (unlikely(!lockref_get_not_dead(&dentry->d_lockref)))
 		goto out;
-	if (unlikely(read_seqcount_retry(&dentry->d_seq, seq))) {
-		rcu_read_unlock();
-		dput(dentry);
-		goto drop_root_mnt;
-	}
+	if (unlikely(read_seqcount_retry(&dentry->d_seq, seq)))
+		goto out_dput;
 	/*
 	 * Sequence counts matched. Now make sure that the root is
 	 * still valid and get it if required.
 	 */
-	if (nd->root.mnt && !(nd->flags & LOOKUP_ROOT)) {
-		if (unlikely(!legitimize_path(nd, &nd->root, nd->root_seq))) {
-			rcu_read_unlock();
-			dput(dentry);
-			return -ECHILD;
-		}
-	}
-
+	if (unlikely(!legitimize_root(nd)))
+		goto out_dput;
 	rcu_read_unlock();
 	return 0;
 
@@ -753,9 +745,10 @@ out1:
 	nd->path.dentry = NULL;
 out:
 	rcu_read_unlock();
-drop_root_mnt:
-	if (!(nd->flags & LOOKUP_ROOT))
-		nd->root.mnt = NULL;
+	return -ECHILD;
+out_dput:
+	rcu_read_unlock();
+	dput(dentry);
 	return -ECHILD;
 }
 
@@ -819,6 +812,7 @@ static void set_root(struct nameidata *nd)
 		} while (read_seqcount_retry(&fs->seq, seq));
 	} else {
 		get_fs_root(fs, &nd->root);
+		nd->flags |= LOOKUP_ROOT_GRABBED;
 	}
 }
 
@@ -1735,8 +1729,6 @@ static int pick_link(struct nameidata *nd, struct path *link,
 				nd->flags &= ~LOOKUP_RCU;
 				nd->path.mnt = NULL;
 				nd->path.dentry = NULL;
-				if (!(nd->flags & LOOKUP_ROOT))
-					nd->root.mnt = NULL;
 				rcu_read_unlock();
 			} else if (likely(unlazy_walk(nd)) == 0)
 				error = nd_alloc_stack(nd);
@@ -2350,7 +2342,7 @@ int filename_lookup(int dfd, struct filename *name, unsigned flags,
 		retval = path_lookupat(&nd, flags | LOOKUP_REVAL, path);
 
 	if (likely(!retval))
-		audit_inode(name, path->dentry, flags & LOOKUP_PARENT);
+		audit_inode(name, path->dentry, 0);
 	restore_nameidata();
 	putname(name);
 	return retval;
@@ -2391,7 +2383,7 @@ static struct filename *filename_parentat(int dfd, struct filename *name,
 	if (likely(!retval)) {
 		*last = nd.last;
 		*type = nd.last_type;
-		audit_inode(name, parent->dentry, LOOKUP_PARENT);
+		audit_inode(name, parent->dentry, AUDIT_INODE_PARENT);
 	} else {
 		putname(name);
 		name = ERR_PTR(retval);
@@ -2718,7 +2710,7 @@ filename_mountpoint(int dfd, struct filename *name, struct path *path,
 	if (unlikely(error == -ESTALE))
 		error = path_mountpoint(&nd, flags | LOOKUP_REVAL, path);
 	if (likely(!error))
-		audit_inode(name, path->dentry, flags & LOOKUP_NO_EVAL);
+		audit_inode(name, path->dentry, AUDIT_INODE_NOEVAL);
 	restore_nameidata();
 	putname(name);
 	return error;
@@ -3299,7 +3291,7 @@ static int do_last(struct nameidata *nd,
 		if (error)
 			return error;
 
-		audit_inode(nd->name, dir, LOOKUP_PARENT);
+		audit_inode(nd->name, dir, AUDIT_INODE_PARENT);
 		/* trailing slashes? */
 		if (unlikely(nd->last.name[nd->last.len]))
 			return -EISDIR;
diff --git a/fs/namespace.c b/fs/namespace.c
index d28d30b13043..81edb7e7ddfd 100644
--- a/fs/namespace.c
+++ b/fs/namespace.c
@@ -1675,8 +1675,6 @@ int ksys_umount(char __user *name, int flags)
 	if (!(flags & UMOUNT_NOFOLLOW))
 		lookup_flags |= LOOKUP_FOLLOW;
 
-	lookup_flags |= LOOKUP_NO_EVAL;
-
 	retval = user_path_mountpoint_at(AT_FDCWD, name, lookup_flags, &path);
 	if (retval)
 		goto out;
@@ -3046,7 +3044,7 @@ long do_mount(const char *dev_name, const char __user *dir_name,
 		return -EINVAL;
 
 	/* ... and get the mountpoint */
-	retval = user_path(dir_name, &path);
+	retval = user_path_at(AT_FDCWD, dir_name, LOOKUP_FOLLOW, &path);
 	if (retval)
 		return retval;
 
@@ -3593,11 +3591,13 @@ SYSCALL_DEFINE2(pivot_root, const char __user *, new_root,
 	if (!may_mount())
 		return -EPERM;
 
-	error = user_path_dir(new_root, &new);
+	error = user_path_at(AT_FDCWD, new_root,
+			     LOOKUP_FOLLOW | LOOKUP_DIRECTORY, &new);
 	if (error)
 		goto out0;
 
-	error = user_path_dir(put_old, &old);
+	error = user_path_at(AT_FDCWD, put_old,
+			     LOOKUP_FOLLOW | LOOKUP_DIRECTORY, &old);
 	if (error)
 		goto out1;
 
diff --git a/fs/nfs/nfstrace.h b/fs/nfs/nfstrace.h
index 976d4089e267..361cc10d6f95 100644
--- a/fs/nfs/nfstrace.h
+++ b/fs/nfs/nfstrace.h
@@ -207,7 +207,6 @@ TRACE_DEFINE_ENUM(LOOKUP_PARENT);
 TRACE_DEFINE_ENUM(LOOKUP_REVAL);
 TRACE_DEFINE_ENUM(LOOKUP_RCU);
 TRACE_DEFINE_ENUM(LOOKUP_NO_REVAL);
-TRACE_DEFINE_ENUM(LOOKUP_NO_EVAL);
 TRACE_DEFINE_ENUM(LOOKUP_OPEN);
 TRACE_DEFINE_ENUM(LOOKUP_CREATE);
 TRACE_DEFINE_ENUM(LOOKUP_EXCL);
@@ -226,7 +225,6 @@ TRACE_DEFINE_ENUM(LOOKUP_DOWN);
 			{ LOOKUP_REVAL, "REVAL" }, \
 			{ LOOKUP_RCU, "RCU" }, \
 			{ LOOKUP_NO_REVAL, "NO_REVAL" }, \
-			{ LOOKUP_NO_EVAL, "NO_EVAL" }, \
 			{ LOOKUP_OPEN, "OPEN" }, \
 			{ LOOKUP_CREATE, "CREATE" }, \
 			{ LOOKUP_EXCL, "EXCL" }, \
diff --git a/fs/xfs/xfs_ioctl.c b/fs/xfs/xfs_ioctl.c
index 6f7848cd5527..affa557c2337 100644
--- a/fs/xfs/xfs_ioctl.c
+++ b/fs/xfs/xfs_ioctl.c
@@ -67,7 +67,7 @@ xfs_find_handle(
 			return -EBADF;
 		inode = file_inode(f.file);
 	} else {
-		error = user_lpath((const char __user *)hreq->path, &path);
+		error = user_path_at(AT_FDCWD, hreq->path, 0, &path);
 		if (error)
 			return error;
 		inode = d_inode(path.dentry);