sysctl: Don't call sysctl_follow_link unless we are a link.

There are no functional changes.  Just code motion to make it
clear that we don't follow a link between sysctl roots unless the
directory entry actually is a link.

Suggested-by:  Lucian Adrian Grijincu <lucian.grijincu@gmail.com>
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
This commit is contained in:
Eric W. Biederman 2012-01-30 21:24:59 -08:00
parent 60f126d93b
commit 4e75732035

View File

@ -451,10 +451,12 @@ static struct dentry *proc_sys_lookup(struct inode *dir, struct dentry *dentry,
if (!p)
goto out;
ret = sysctl_follow_link(&h, &p, current->nsproxy);
err = ERR_PTR(ret);
if (ret)
goto out;
if (S_ISLNK(p->mode)) {
ret = sysctl_follow_link(&h, &p, current->nsproxy);
err = ERR_PTR(ret);
if (ret)
goto out;
}
err = ERR_PTR(-ENOMEM);
inode = proc_sys_make_inode(dir->i_sb, h ? h : head, p);
@ -601,10 +603,12 @@ static int proc_sys_link_fill_cache(struct file *filp, void *dirent,
int err, ret = 0;
head = sysctl_head_grab(head);
/* It is not an error if we can not follow the link ignore it */
err = sysctl_follow_link(&head, &table, current->nsproxy);
if (err)
goto out;
if (S_ISLNK(table->mode)) {
/* It is not an error if we can not follow the link ignore it */
err = sysctl_follow_link(&head, &table, current->nsproxy);
if (err)
goto out;
}
ret = proc_sys_fill_cache(filp, dirent, filldir, head, table);
out:
@ -950,10 +954,6 @@ static int sysctl_follow_link(struct ctl_table_header **phead,
struct ctl_dir *dir;
int ret;
/* Get out quickly if not a link */
if (!S_ISLNK((*pentry)->mode))
return 0;
ret = 0;
spin_lock(&sysctl_lock);
root = (*pentry)->data;