lkml.org 
[lkml]   [2012]   [Apr]   [5]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH 05/34] vfs: make follow_link check RCU safe
Date
From: Miklos Szeredi <mszeredi@suse.cz>

This will allow this code to be used in RCU mode.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
---
fs/namei.c | 12 ++++++++++--
1 files changed, 10 insertions(+), 2 deletions(-)

diff --git a/fs/namei.c b/fs/namei.c
index 58d1f62..a94b0d4 100644
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -2232,6 +2232,7 @@ 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;
@@ -2263,7 +2264,6 @@ 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))
@@ -2394,8 +2394,16 @@ 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


\
 
 \ /
  Last update: 2012-04-05 17:11    [W:0.087 / U:0.068 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site