namei: don't unlazy until get_link() (bc40aee0) · Commits · e / devices / android_kernel_fairphone_FP3

fs/namei.c

+26 −11

Original line number	Diff line number	Diff line
		@@ -536,10 +536,19 @@ static void restore_nameidata(struct nameidata *old)

		static int __nd_alloc_stack(struct nameidata *nd)
		{
		struct saved p = kmalloc(MAXSYMLINKS sizeof(struct saved),
		struct saved *p;

		if (nd->flags & LOOKUP_RCU) {
		p= kmalloc(MAXSYMLINKS * sizeof(struct saved),
		GFP_ATOMIC);
		if (unlikely(!p))
		return -ECHILD;
		} else {
		p= kmalloc(MAXSYMLINKS * sizeof(struct saved),
		GFP_KERNEL);
		if (unlikely(!p))
		return -ENOMEM;
		}
		memcpy(p, nd->internal, sizeof(nd->internal));
		nd->stack = p;
		return 0;
		@@ -957,8 +966,10 @@ const char get_link(struct nameidata nd)
		int error;
		const char *res;

		BUG_ON(nd->flags & LOOKUP_RCU);

		if (nd->flags & LOOKUP_RCU) {
		if (unlikely(unlazy_walk(nd, NULL, 0)))
		return ERR_PTR(-ECHILD);
		}
		cond_resched();

		touch_atime(&last->link);
		@@ -1623,18 +1634,22 @@ static int pick_link(struct nameidata nd, struct path link,
		path_to_nameidata(link, nd);
		return -ELOOP;
		}
		if (nd->flags & LOOKUP_RCU) {
		if (unlikely(unlazy_link(nd, link, seq)))
		return -ECHILD;
		} else {
		if (!(nd->flags & LOOKUP_RCU)) {
		if (link->mnt == nd->path.mnt)
		mntget(link->mnt);
		}
		error = nd_alloc_stack(nd);
		if (unlikely(error)) {
		if (error == -ECHILD) {
		if (unlikely(unlazy_link(nd, link, seq)))
		return -ECHILD;
		error = nd_alloc_stack(nd);
		}
		if (error) {
		path_put(link);
		return error;
		}
		}

		last = nd->stack + nd->depth++;
		last->link = *link;