X-Git-Url: https://asedeno.scripts.mit.edu/gitweb/?a=blobdiff_plain;f=fs%2Fnamei.c;h=671c3c1a3425bab83d07a6b1091360dc7d03b9f0;hb=28de978ba346f4d5baee4e59841b473a7ff38f0d;hp=209c51a5226c9cf1529e50c9696d09c469c3e2ab;hpb=e0f14b8ca3882988d15f0b1b853ae3c29d8c9a83;p=linux.git

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 @@ static int unlazy_child(struct nameidata *nd, struct dentry *dentry, unsigned se
 	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;