clear RCU on all failure exits from link_path_walk() (4455ca62) · Commits · 戴 / test

fs/namei.c

+16 −14

Original line number	Diff line number	Diff line
		@@ -1405,8 +1405,9 @@ static int link_path_walk(const char name, struct nameidata nd)
		* parent relationships.
		*/
		if (unlikely(type != LAST_NORM)) {
		if (handle_dots(nd, type))
		return -ECHILD;
		err = handle_dots(nd, type);
		if (err)
		goto return_err;
		continue;
		}

		@@ -1441,8 +1442,9 @@ last_component:
		if (lookup_flags & LOOKUP_PARENT)
		goto lookup_parent;
		if (unlikely(type != LAST_NORM)) {
		if (handle_dots(nd, type))
		return -ECHILD;
		err = handle_dots(nd, type);
		if (err)
		goto return_err;
		return 0;
		}
		err = do_lookup(nd, &this, &next, &inode);
		@@ -1475,6 +1477,12 @@ lookup_parent:
		if (!(nd->flags & LOOKUP_RCU))
		path_put(&nd->path);
		return_err:
		if (nd->flags & LOOKUP_RCU) {
		nd->flags &= ~LOOKUP_RCU;
		nd->root.mnt = NULL;
		rcu_read_unlock();
		br_read_unlock(vfsmount_lock);
		}
		return err;
		}

		@@ -1585,16 +1593,10 @@ static int path_lookupat(int dfd, const char *name,
		retval = link_path_walk(name, nd);

		if (nd->flags & LOOKUP_RCU) {
		/* RCU dangling. Cancel it. */
		if (!retval) {
		/* went all way through without dropping RCU */
		BUG_ON(retval);
		if (nameidata_drop_rcu_last(nd))
		retval = -ECHILD;
		} else {
		nd->flags &= ~LOOKUP_RCU;
		nd->root.mnt = NULL;
		rcu_read_unlock();
		br_read_unlock(vfsmount_lock);
		}
		}

		if (!retval)