Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754052Ab2EUPaY (ORCPT ); Mon, 21 May 2012 11:30:24 -0400 Received: from mail-bk0-f46.google.com ([209.85.214.46]:60065 "EHLO mail-bk0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753529Ab2EUPaS (ORCPT ); Mon, 21 May 2012 11:30:18 -0400 From: Miklos Szeredi To: viro@ZenIV.linux.org.uk Cc: linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, hch@infradead.org, torvalds@linux-foundation.org, mszeredi@suse.cz Subject: [PATCH 05/16] vfs: make follow_link check RCU safe Date: Mon, 21 May 2012 17:30:09 +0200 Message-Id: <1337614220-6174-6-git-send-email-miklos@szeredi.hu> X-Mailer: git-send-email 1.7.7 In-Reply-To: <1337614220-6174-1-git-send-email-miklos@szeredi.hu> References: <1337614220-6174-1-git-send-email-miklos@szeredi.hu> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1575 Lines: 55 From: Miklos Szeredi This will allow this code to be used in RCU mode. Signed-off-by: Miklos Szeredi --- fs/namei.c | 12 ++++++++++-- 1 files changed, 10 insertions(+), 2 deletions(-) diff --git a/fs/namei.c b/fs/namei.c index 1dba4a7..67bddd6 100644 --- a/fs/namei.c +++ b/fs/namei.c @@ -2203,6 +2203,7 @@ static struct file *do_last(struct nameidata *nd, struct path *path, int acc_mode = op->acc_mode; struct file *filp; struct inode *inode; + int symlink_ok = 0; int error; nd->flags &= ~LOOKUP_PARENT; @@ -2234,7 +2235,6 @@ static struct file *do_last(struct nameidata *nd, struct path *path, } if (!(open_flag & O_CREAT)) { - int symlink_ok = 0; if (nd->last.name[nd->last.len]) nd->flags |= LOOKUP_FOLLOW | LOOKUP_DIRECTORY; if (open_flag & O_PATH && !(nd->flags & LOOKUP_FOLLOW)) @@ -2366,8 +2366,16 @@ static struct file *do_last(struct nameidata *nd, struct path *path, if (!inode) goto exit_dput; - if (inode->i_op->follow_link) + if (should_follow_link(inode, !symlink_ok)) { + if (nd->flags & LOOKUP_RCU) { + if (unlikely(unlazy_walk(nd, path->dentry))) { + error = -ECHILD; + goto exit; + } + } + BUG_ON(inode != path->dentry->d_inode); return NULL; + } path_to_nameidata(path, nd); nd->inode = inode; -- 1.7.7 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/