From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-9.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 77E01C32771 for ; Sun, 19 Jan 2020 03:24:50 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 52AB6214AF for ; Sun, 19 Jan 2020 03:24:50 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726442AbgASDYq (ORCPT ); Sat, 18 Jan 2020 22:24:46 -0500 Received: from zeniv.linux.org.uk ([195.92.253.2]:56938 "EHLO ZenIV.linux.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725497AbgASDYq (ORCPT ); Sat, 18 Jan 2020 22:24:46 -0500 Received: from viro by ZenIV.linux.org.uk with local (Exim 4.92.3 #3 (Red Hat Linux)) id 1it1Bt-00BFgY-Oz; Sun, 19 Jan 2020 03:24:00 +0000 From: Al Viro To: linux-fsdevel@vger.kernel.org Cc: Linus Torvalds , linux-kernel@vger.kernel.org, Aleksa Sarai , David Howells , Eric Biederman , Christian Brauner , Al Viro Subject: [PATCH 3/9] merging pick_link() with get_link(), part 3 Date: Sun, 19 Jan 2020 03:17:32 +0000 Message-Id: <20200119031738.2681033-20-viro@ZenIV.linux.org.uk> X-Mailer: git-send-email 2.24.1 In-Reply-To: <20200119031738.2681033-1-viro@ZenIV.linux.org.uk> References: <20200119031423.GV8904@ZenIV.linux.org.uk> <20200119031738.2681033-1-viro@ZenIV.linux.org.uk> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-fsdevel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org From: Al Viro After a pure jump ("/" or procfs-style symlink) we don't need to hold the link anymore. link_path_walk() dropped it if such case had been detected, lookup_last/do_last() (i.e. old trailing_symlink()) left it on the stack - it ended up calling terminate_walk() shortly anyway, which would've purged the entire stack. Do it in get_link() itself instead. Simpler logics that way... Signed-off-by: Al Viro --- fs/namei.c | 18 +++++++++--------- 1 file changed, 9 insertions(+), 9 deletions(-) diff --git a/fs/namei.c b/fs/namei.c index d93e155caded..fe03e4d1144b 100644 --- a/fs/namei.c +++ b/fs/namei.c @@ -1153,7 +1153,9 @@ const char *get_link(struct nameidata *nd) } else { res = get(dentry, inode, &last->done); } - if (IS_ERR_OR_NULL(res)) + if (!res) + goto all_done; + if (IS_ERR(res)) return res; } if (*res == '/') { @@ -1163,9 +1165,11 @@ const char *get_link(struct nameidata *nd) while (unlikely(*++res == '/')) ; } - if (!*res) - res = NULL; - return res; + if (*res) + return res; +all_done: // pure jump + put_link(nd); + return NULL; } /* @@ -2210,11 +2214,7 @@ static int link_path_walk(const char *name, struct nameidata *nd) if (IS_ERR(s)) return PTR_ERR(s); - err = 0; - if (unlikely(!s)) { - /* jumped */ - put_link(nd); - } else { + if (likely(s)) { nd->stack[nd->depth - 1].name = name; name = s; continue; -- 2.20.1