From patchwork Tue May 5 05:22:46 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Al Viro X-Patchwork-Id: 6334791 Return-Path: X-Original-To: patchwork-linux-fsdevel@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork1.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork1.web.kernel.org (Postfix) with ESMTP id 45B5C9F32E for ; Tue, 5 May 2015 05:34:48 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 7824A20268 for ; Tue, 5 May 2015 05:34:47 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 84F6E20266 for ; Tue, 5 May 2015 05:34:46 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S965566AbbEEFen (ORCPT ); Tue, 5 May 2015 01:34:43 -0400 Received: from zeniv.linux.org.uk ([195.92.253.2]:40034 "EHLO ZenIV.linux.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755626AbbEEFXH (ORCPT ); Tue, 5 May 2015 01:23:07 -0400 Received: from viro by ZenIV.linux.org.uk with local (Exim 4.76 #1 (Red Hat Linux)) id 1YpVJx-0001Oa-As; Tue, 05 May 2015 05:23:05 +0000 From: Al Viro To: Linus Torvalds Cc: Neil Brown , Christoph Hellwig , linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org Subject: [PATCH 72/79] namei: move link count check and stack allocation into pick_link() Date: Tue, 5 May 2015 06:22:46 +0100 Message-Id: <1430803373-4948-72-git-send-email-viro@ZenIV.linux.org.uk> X-Mailer: git-send-email 1.7.7.6 In-Reply-To: <20150505052205.GS889@ZenIV.linux.org.uk> References: <20150505052205.GS889@ZenIV.linux.org.uk> Sender: linux-fsdevel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org X-Spam-Status: No, score=-6.9 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_HI, T_RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP From: Al Viro Signed-off-by: Al Viro --- fs/namei.c | 27 ++++++++++++--------------- 1 file changed, 12 insertions(+), 15 deletions(-) diff --git a/fs/namei.c b/fs/namei.c index 026d7df..9822b37 100644 --- a/fs/namei.c +++ b/fs/namei.c @@ -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); @@ -1560,12 +1554,23 @@ 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; } @@ -1832,15 +1837,7 @@ 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);