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 D0876C3F2D1 for ; Sun, 1 Mar 2020 21:53:06 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 9E96A246BB for ; Sun, 1 Mar 2020 21:53:06 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727322AbgCAVxF (ORCPT ); Sun, 1 Mar 2020 16:53:05 -0500 Received: from zeniv.linux.org.uk ([195.92.253.2]:41730 "EHLO ZenIV.linux.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727189AbgCAVwt (ORCPT ); Sun, 1 Mar 2020 16:52:49 -0500 Received: from viro by ZenIV.linux.org.uk with local (Exim 4.92.3 #3 (Red Hat Linux)) id 1j8WW0-003fQO-9C; Sun, 01 Mar 2020 21:52:48 +0000 From: Al Viro To: linux-fsdevel@vger.kernel.org Cc: linux-kernel@vger.kernel.org, Linus Torvalds Subject: [RFC][PATCH v3 48/55] follow_dotdot{,_rcu}(): switch to use of step_into() Date: Sun, 1 Mar 2020 21:52:33 +0000 Message-Id: <20200301215240.873899-48-viro@ZenIV.linux.org.uk> X-Mailer: git-send-email 2.24.1 In-Reply-To: <20200301215240.873899-1-viro@ZenIV.linux.org.uk> References: <20200301215125.GA873525@ZenIV.linux.org.uk> <20200301215240.873899-1-viro@ZenIV.linux.org.uk> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Al Viro gets the regular mount crossing on result of .. Signed-off-by: Al Viro --- fs/namei.c | 37 +++++++++---------------------------- 1 file changed, 9 insertions(+), 28 deletions(-) diff --git a/fs/namei.c b/fs/namei.c index 3e3bf11ee3d7..cc01bca2266c 100644 --- a/fs/namei.c +++ b/fs/namei.c @@ -1724,35 +1724,19 @@ static const char *follow_dotdot_rcu(struct nameidata *nd, int flags) /* we know that mountpoint was pinned */ nd->path.dentry = mountpoint; nd->path.mnt = &mparent->mnt; - inode = inode2; + inode = nd->inode = inode2; nd->seq = seq; } } if (unlikely(!parent)) { if (unlikely(nd->flags & LOOKUP_BENEATH)) return ERR_PTR(-ECHILD); + return step_into(nd, flags | WALK_NOFOLLOW, + nd->path.dentry, nd->inode, nd->seq); } else { - nd->path.dentry = parent; - nd->seq = seq; - } - while (unlikely(d_mountpoint(nd->path.dentry))) { - struct mount *mounted; - mounted = __lookup_mnt(nd->path.mnt, nd->path.dentry); - if (unlikely(read_seqretry(&mount_lock, nd->m_seq))) - return ERR_PTR(-ECHILD); - if (!mounted) - break; - if (unlikely(nd->flags & LOOKUP_NO_XDEV)) - return ERR_PTR(-ECHILD); - nd->path.mnt = &mounted->mnt; - nd->path.dentry = mounted->mnt.mnt_root; - inode = nd->path.dentry->d_inode; - nd->seq = read_seqcount_begin(&nd->path.dentry->d_seq); + return step_into(nd, flags | WALK_NOFOLLOW, + parent, inode, seq); } - nd->inode = inode; - if (!(flags & WALK_MORE) && nd->depth) - put_link(nd); - return NULL; } static const char *follow_dotdot(struct nameidata *nd, int flags) @@ -1778,15 +1762,12 @@ static const char *follow_dotdot(struct nameidata *nd, int flags) if (unlikely(!parent)) { if (unlikely(nd->flags & LOOKUP_BENEATH)) return ERR_PTR(-EXDEV); + return step_into(nd, flags | WALK_NOFOLLOW, + dget(nd->path.dentry), nd->inode, nd->seq); } else { - dput(nd->path.dentry); - nd->path.dentry = parent; + return step_into(nd, flags | WALK_NOFOLLOW, + parent, parent->d_inode, 0); } - follow_mount(&nd->path); - nd->inode = nd->path.dentry->d_inode; - if (!(flags & WALK_MORE) && nd->depth) - put_link(nd); - return NULL; } static const char *handle_dots(struct nameidata *nd, int type, int flags) -- 2.11.0