namei: don't bother with ->follow_link() if ->i_link is set (d4dee48b) · Commits · 戴 / test

fs/namei.c

+13 −7

Original line number	Diff line number	Diff line
		@@ -865,12 +865,15 @@ get_link(struct path link, struct nameidata nd, void **p)

		nd->last_type = LAST_BIND;
		*p = NULL;
		res = inode->i_link;
		if (!res) {
		res = inode->i_op->follow_link(dentry, p, nd);
		if (IS_ERR(res)) {
		out:
		path_put(&nd->path);
		path_put(link);
		}
		}
		return res;
		}

		@@ -4418,11 +4421,14 @@ EXPORT_SYMBOL(readlink_copy);
		int generic_readlink(struct dentry dentry, char __user buffer, int buflen)
		{
		void *cookie;
		const char *link = dentry->d_inode->i_op->follow_link(dentry, &cookie, NULL);
		const char *link = dentry->d_inode->i_link;
		int res;

		if (!link) {
		link = dentry->d_inode->i_op->follow_link(dentry, &cookie, NULL);
		if (IS_ERR(link))
		return PTR_ERR(link);
		}
		res = readlink_copy(buffer, buflen, link);
		if (cookie && dentry->d_inode->i_op->put_link)
		dentry->d_inode->i_op->put_link(dentry, cookie);