On Mon, 10 Dec 2007 17:05:30 +0200
Maxim Levitsky <maximlevitsky@gmail.com> wrote:
argh, this is getting bad.
Can you please test the below patch asap? Against 2.6.24-rc4 or latest-linus.
From: Andrew Morton <akpm@linux-foundation.org>
Revert
commit 2b1e300a9dfc3196ccddf6f1d74b91b7af55e416
Author: Eric W. Biederman <ebiederm@xmission.com>
Date: Sun Dec 2 00:33:17 2007 +1100
[NETNS]: Fix /proc/net breakage
It has caused all sorts of procfs mayhem.
Reverting this will reintroduce
"Currently things work but there are odd details visible to user
space, even when we have a single network namespace."
Where "details" was never elaborated upon.
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Pavel Emelyanov <xemul@openvz.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
Cc: Trond Myklebust <trond.myklebust@fys.uio.no>
Cc: "Denis V. Lunev" <den@openvz.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---
fs/proc/generic.c | 12 -----
fs/proc/proc_net.c | 86 +++++++++++++++++++++++++++++++++++---
include/linux/proc_fs.h | 3 -
3 files changed, 82 insertions(+), 19 deletions(-)
diff -puN fs/proc/generic.c~revert-fix-proc-net-breakage fs/proc/generic.c
--- a/fs/proc/generic.c~revert-fix-proc-net-breakage
+++ a/fs/proc/generic.c
@@ -374,16 +374,9 @@ static int proc_delete_dentry(struct den
return 1;
}
-static int proc_revalidate_dentry(struct dentry *dentry, struct nameidata *nd)
-{
- d_drop(dentry);
- return 0;
-}
-
static struct dentry_operations proc_dentry_operations =
{
.d_delete = proc_delete_dentry,
- .d_revalidate = proc_revalidate_dentry,
};
/*
@@ -404,11 +397,8 @@ struct dentry *proc_lookup(struct inode
if (de->namelen != dentry->d_name.len)
continue;
if (!memcmp(dentry->d_name.name, de->name, de->namelen)) {
- unsigned int ino;
+ unsigned int ino = de->low_ino;
- if (de->shadow_proc)
- de = de->shadow_proc(current, de);
- ino = de->low_ino;
de_get(de);
spin_unlock(&proc_subdir_lock);
error = -EINVAL;
diff -puN fs/proc/proc_net.c~revert-fix-proc-net-breakage fs/proc/proc_net.c
--- a/fs/proc/proc_net.c~revert-fix-proc-net-breakage
+++ a/fs/proc/proc_net.c
@@ -50,14 +50,89 @@ struct net *get_proc_net(const struct in
}
EXPORT_SYMBOL_GPL(get_proc_net);
-static struct proc_dir_entry *shadow_pde;
+static struct proc_dir_entry *proc_net_shadow;
-static struct proc_dir_entry *proc_net_shadow(struct task_struct *task,
+static struct dentry *proc_net_shadow_dentry(struct dentry *parent,
struct proc_dir_entry *de)
{
- return task->nsproxy->net_ns->proc_net;
+ struct dentry *shadow = NULL;
+ struct inode *inode;
+ if (!de)
+ goto out;
+ de_get(de);
+ inode = proc_get_inode(parent->d_inode->i_sb, de->low_ino, de);
+ if (!inode)
+ goto out_de_put;
+ shadow = d_alloc_name(parent, de->name);
+ if (!shadow)
+ goto out_iput;
+ shadow->d_op = parent->d_op; /* proc_dentry_operations */
+ d_instantiate(shadow, inode);
+out:
+ return shadow;
+out_iput:
+ iput(inode);
+out_de_put:
+ de_put(de);
+ goto out;
+}
+
+static void *proc_net_follow_link(struct dentry *parent, struct nameidata *nd)
+{
+ struct net *net = current->nsproxy->net_ns;
+ struct dentry *shadow;
+ shadow = proc_net_shadow_dentry(parent, net->proc_net);
+ if (!shadow)
+ return ERR_PTR(-ENOENT);
+
+ dput(nd->dentry);
+ /* My dentry count is 1 and that should be enough as the
+ * shadow dentry is thrown away immediately.
+ */
+ nd->dentry = shadow;
+ return NULL;
}
+static struct dentry *proc_net_lookup(struct inode *dir, struct dentry *dentry,
+ struct nameidata *nd)
+{
+ struct net *net = current->nsproxy->net_ns;
+ struct dentry *shadow;
+
+ shadow = proc_net_shadow_dentry(nd->dentry, net->proc_net);
+ if (!shadow)
+ return ERR_PTR(-ENOENT);
+
+ dput(nd->dentry);
+ nd->dentry = shadow;
+
+ return shadow->d_inode->i_op->lookup(shadow->d_inode, dentry, nd);
+}
+
+static int proc_net_setattr(struct dentry *dentry, struct iattr *iattr)
+{
+ struct net *net = current->nsproxy->net_ns;
+ struct dentry *shadow;
+ int ret;
+
+ shadow = proc_net_shadow_dentry(dentry->d_parent, net->proc_net);
+ if (!shadow)
+ return -ENOENT;
+ ret = shadow->d_inode->i_op->setattr(shadow, iattr);
+ dput(shadow);
+ return ret;
+}
+
+static const struct file_operations proc_net_dir_operations = {
+ .read = generic_read_dir,
+};
+
+static struct inode_operations proc_net_dir_inode_operations = {
+ .follow_link = proc_net_follow_link,
+ .lookup = proc_net_lookup,
+ .setattr = proc_net_setattr,
+};
+
static __net_init int proc_net_ns_init(struct net *net)
{
struct proc_dir_entry *root, *netd, *net_statd;
@@ -110,8 +185,9 @@ static struct pernet_operations __net_in
int __init proc_net_init(void)
{
- shadow_pde = proc_mkdir("net", NULL);
- shadow_pde->shadow_proc = proc_net_shadow;
+ proc_net_shadow = proc_mkdir("net", NULL);
+ proc_net_shadow->proc_iops = &proc_net_dir_inode_operations;
+ proc_net_shadow->proc_fops = &proc_net_dir_operations;
return register_pernet_subsys(&proc_net_ns_ops);
}
diff -puN include/linux/proc_fs.h~revert-fix-proc-net-breakage include/linux/proc_fs.h
--- a/include/linux/proc_fs.h~revert-fix-proc-net-breakage
+++ a/include/linux/proc_fs.h
@@ -48,8 +48,6 @@ typedef int (read_proc_t)(char *page, ch
typedef int (write_proc_t)(struct file *file, const char __user *buffer,
unsigned long count, void *data);
typedef int (get_info_t)(char *, char **, off_t, int);
-typedef struct proc_dir_entry *(shadow_proc_t)(struct task_struct *task,
- struct proc_dir_entry *pde);
struct proc_dir_entry {
unsigned int low_ino;
@@ -80,7 +78,6 @@ struct proc_dir_entry {
int pde_users; /* number of callers into module in progress */
spinlock_t pde_unload_lock; /* proc_fops checks and pde_users bumps */
struct completion *pde_unload_completion;
- shadow_proc_t *shadow_proc;
};
struct kcore_list {
_
--
