lkml.org 
[lkml]   [2015]   [May]   [11]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH v3 050/110] namei: trim the arguments of get_link()
Date
From: Al Viro <viro@zeniv.linux.org.uk>

same story as the previous commit

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
---
fs/namei.c | 45 +++++++++++++++++++++------------------------
1 file changed, 21 insertions(+), 24 deletions(-)

diff --git a/fs/namei.c b/fs/namei.c
index 1ac3217..e5715a5 100644
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -843,27 +843,33 @@ static int may_linkat(struct path *link)
return -EPERM;
}

-static __always_inline const char *
-get_link(struct path *link, struct nameidata *nd, void **p)
+static __always_inline
+const char *get_link(struct nameidata *nd)
{
- struct dentry *dentry = link->dentry;
+ struct saved *last = nd->stack + nd->depth;
+ struct dentry *dentry = nd->link.dentry;
struct inode *inode = dentry->d_inode;
int error;
const char *res;

BUG_ON(nd->flags & LOOKUP_RCU);

- if (link->mnt == nd->path.mnt)
- mntget(link->mnt);
+ if (nd->link.mnt == nd->path.mnt)
+ mntget(nd->link.mnt);

- res = ERR_PTR(-ELOOP);
- if (unlikely(current->total_link_count >= 40))
- goto out;
+ if (unlikely(current->total_link_count >= 40)) {
+ path_put(&nd->path);
+ path_put(&nd->link);
+ return ERR_PTR(-ELOOP);
+ }
+
+ last->link = nd->link;
+ last->cookie = NULL;

cond_resched();
current->total_link_count++;

- touch_atime(link);
+ touch_atime(&last->link);

error = security_inode_follow_link(dentry);
res = ERR_PTR(error);
@@ -871,14 +877,13 @@ get_link(struct path *link, struct nameidata *nd, void **p)
goto out;

nd->last_type = LAST_BIND;
- *p = NULL;
res = inode->i_link;
if (!res) {
- res = inode->i_op->follow_link(dentry, p, nd);
+ res = inode->i_op->follow_link(dentry, &last->cookie, nd);
if (IS_ERR(res)) {
out:
path_put(&nd->path);
- path_put(link);
+ path_put(&last->link);
}
}
return res;
@@ -1717,7 +1722,6 @@ static inline u64 hash_name(const char *name)
*/
static int link_path_walk(const char *name, struct nameidata *nd)
{
- struct saved *last = nd->stack;
int err;

while (*name=='/')
@@ -1795,16 +1799,13 @@ Walked:

nd->depth++;
current->link_count++;
- last++;

- last->link = nd->link;
- s = get_link(&last->link, nd, &last->cookie);
+ s = get_link(nd);

if (unlikely(IS_ERR(s))) {
err = PTR_ERR(s);
current->link_count--;
nd->depth--;
- last--;
goto Err;
}
err = 0;
@@ -1813,7 +1814,6 @@ Walked:
put_link(nd);
current->link_count--;
nd->depth--;
- last--;
} else {
if (*s == '/') {
if (!nd->root.mnt)
@@ -1826,7 +1826,7 @@ Walked:
;
}
nd->inode = nd->path.dentry->d_inode;
- last->name = name;
+ nd->stack[nd->depth].name = name;
if (!*s)
goto OK;
name = s;
@@ -1844,17 +1844,15 @@ Err:
put_link(nd);
current->link_count--;
nd->depth--;
- last--;
}
return err;
OK:
if (unlikely(nd->depth)) {
- name = last->name;
+ name = nd->stack[nd->depth].name;
err = walk_component(nd, LOOKUP_FOLLOW);
put_link(nd);
current->link_count--;
nd->depth--;
- last--;
goto Walked;
}
return 0;
@@ -1979,8 +1977,7 @@ static int trailing_symlink(struct nameidata *nd)
if (unlikely(error))
return error;
nd->flags |= LOOKUP_PARENT;
- nd->stack[0].link = nd->link;
- s = get_link(&nd->stack[0].link, nd, &nd->stack[0].cookie);
+ s = get_link(nd);
if (unlikely(IS_ERR(s)))
return PTR_ERR(s);
if (unlikely(!s))
--
2.1.4


\
 
 \ /
  Last update: 2015-05-11 21:01    [W:0.655 / U:18.256 seconds]
©2003-2018 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site