namei: move link count check and stack allocation into pick_link() (626de996) · Commits · 戴 / test

fs/namei.c

+12 −15

Original line number	Diff line number	Diff line
		@@ -891,16 +891,10 @@ const char get_link(struct nameidata nd)
		if (nd->link.mnt == nd->path.mnt)
		mntget(nd->link.mnt);

		if (unlikely(current->total_link_count >= MAXSYMLINKS)) {
		path_put(&nd->link);
		return ERR_PTR(-ELOOP);
		}

		last->link = nd->link;
		last->cookie = NULL;

		cond_resched();
		current->total_link_count++;

		touch_atime(&last->link);

		@@ -1568,12 +1562,23 @@ static void terminate_walk(struct nameidata *nd)

		static int pick_link(struct nameidata nd, struct path link)
		{
		int error;
		if (unlikely(current->total_link_count++ >= MAXSYMLINKS)) {
		path_to_nameidata(link, nd);
		return -ELOOP;
		}
		if (nd->flags & LOOKUP_RCU) {
		if (unlikely(nd->path.mnt != link->mnt \|\|
		unlazy_walk(nd, link->dentry))) {
		return -ECHILD;
		}
		}
		error = nd_alloc_stack(nd);
		if (unlikely(error)) {
		path_to_nameidata(link, nd);
		return error;
		}

		nd->link = *link;
		return 1;
		}
		@@ -1840,15 +1845,7 @@ OK:
		break;

		if (err) {
		const char *s;

		err = nd_alloc_stack(nd);
		if (unlikely(err)) {
		path_to_nameidata(&nd->link, nd);
		break;
		}

		s = get_link(nd);
		const char *s = get_link(nd);

		if (unlikely(IS_ERR(s))) {
		err = PTR_ERR(s);