8 files changed, 80 insertions, 139 deletions

diff --git a/fs/proc/proc_net.c b/fs/proc/proc_net.c
index 0afe21ee0607..cfc4f6c072f1 100644
--- a/fs/proc/proc_net.c
+++ b/fs/proc/proc_net.c
@@ -22,10 +22,48 @@
 #include <linux/mount.h>
 #include <linux/nsproxy.h>
 #include <net/net_namespace.h>
+#include <linux/seq_file.h>
 
 #include "internal.h"
 
 
+int seq_open_net(struct inode *ino, struct file *f,
+                 const struct seq_operations *ops, int size)
+{
+        struct net *net;
+        struct seq_net_private *p;
+
+        BUG_ON(size < sizeof(*p));
+
+        net = get_proc_net(ino);
+        if (net == NULL)
+                return -ENXIO;
+
+        p = __seq_open_private(f, ops, size);
+        if (p == NULL) {
+                put_net(net);
+                return -ENOMEM;
+        }
+        p->net = net;
+        return 0;
+}
+EXPORT_SYMBOL_GPL(seq_open_net);
+
+int seq_release_net(struct inode *ino, struct file *f)
+{
+        struct seq_file *seq;
+        struct seq_net_private *p;
+
+        seq = f->private_data;
+        p = seq->private;
+
+        put_net(p->net);
+        seq_release_private(ino, f);
+        return 0;
+}
+EXPORT_SYMBOL_GPL(seq_release_net);
+
+
 struct proc_dir_entry *proc_net_fops_create(struct net *net,
         const char *name, mode_t mode, const struct file_operations *fops)
 {
diff --git a/include/linux/seq_file.h b/include/linux/seq_file.h
index ebbc02b325fc..648dfeb444db 100644
--- a/include/linux/seq_file.h
+++ b/include/linux/seq_file.h
@@ -63,5 +63,18 @@ extern struct list_head *seq_list_start_head(struct list_head *head,
 extern struct list_head *seq_list_next(void *v, struct list_head *head,
                 loff_t *ppos);
 
+struct net;
+struct seq_net_private {
+        struct net *net;
+};
+
+int seq_open_net(struct inode *, struct file *,
+                 const struct seq_operations *, int);
+int seq_release_net(struct inode *, struct file *);
+static inline struct net *seq_file_net(struct seq_file *seq)
+{
+        return ((struct seq_net_private *)seq->private)->net;
+}
+
 #endif
 #endif
diff --git a/net/core/dev.c b/net/core/dev.c
index 0879f52115eb..d0e23d8310ff 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -2364,7 +2364,7 @@ static int dev_ifconf(struct net *net, char __user *arg)
  */
 void *dev_seq_start(struct seq_file *seq, loff_t *pos)
 {
-        struct net *net = seq->private;
+        struct net *net = seq_file_net(seq);
         loff_t off;
         struct net_device *dev;
 
@@ -2382,7 +2382,7 @@ void *dev_seq_start(struct seq_file *seq, loff_t *pos)
 
 void *dev_seq_next(struct seq_file *seq, void *v, loff_t *pos)
 {
-        struct net *net = seq->private;
+        struct net *net = seq_file_net(seq);
         ++*pos;
         return v == SEQ_START_TOKEN ?
                 first_net_device(net) : next_net_device((struct net_device *)v);
@@ -2481,26 +2481,8 @@ static const struct seq_operations dev_seq_ops = {
 
 static int dev_seq_open(struct inode *inode, struct file *file)
 {
-        struct seq_file *seq;
-        int res;
-        res =  seq_open(file, &dev_seq_ops);
-        if (!res) {
-                seq = file->private_data;
-                seq->private = get_proc_net(inode);
-                if (!seq->private) {
-                        seq_release(inode, file);
-                        res = -ENXIO;
-                }
-        }
-        return res;
-}
-
-static int dev_seq_release(struct inode *inode, struct file *file)
-{
-        struct seq_file *seq = file->private_data;
-        struct net *net = seq->private;
-        put_net(net);
-        return seq_release(inode, file);
+        return seq_open_net(inode, file, &dev_seq_ops,
+                            sizeof(struct seq_net_private));
 }
 
 static const struct file_operations dev_seq_fops = {
@@ -2508,7 +2490,7 @@ static const struct file_operations dev_seq_fops = {
         .open    = dev_seq_open,
         .read    = seq_read,
         .llseek  = seq_lseek,
-        .release = dev_seq_release,
+        .release = seq_release_net,
 };
 
 static const struct seq_operations softnet_seq_ops = {
diff --git a/net/core/dev_mcast.c b/net/core/dev_mcast.c
index 69fff16ece10..63f0b33d7ced 100644
--- a/net/core/dev_mcast.c
+++ b/net/core/dev_mcast.c
@@ -187,7 +187,7 @@ EXPORT_SYMBOL(dev_mc_unsync);
 #ifdef CONFIG_PROC_FS
 static void *dev_mc_seq_start(struct seq_file *seq, loff_t *pos)
 {
-        struct net *net = seq->private;
+        struct net *net = seq_file_net(seq);
         struct net_device *dev;
         loff_t off = 0;
 
@@ -241,26 +241,8 @@ static const struct seq_operations dev_mc_seq_ops = {
 
 static int dev_mc_seq_open(struct inode *inode, struct file *file)
 {
-        struct seq_file *seq;
-        int res;
-        res = seq_open(file, &dev_mc_seq_ops);
-        if (!res) {
-                seq = file->private_data;
-                seq->private = get_proc_net(inode);
-                if (!seq->private) {
-                        seq_release(inode, file);
-                        res = -ENXIO;
-                }
-        }
-        return res;
-}
-
-static int dev_mc_seq_release(struct inode *inode, struct file *file)
-{
-        struct seq_file *seq = file->private_data;
-        struct net *net = seq->private;
-        put_net(net);
-        return seq_release(inode, file);
+        return seq_open_net(inode, file, &dev_mc_seq_ops,
+                            sizeof(struct seq_net_private));
 }
 
 static const struct file_operations dev_mc_seq_fops = {
@@ -268,7 +250,7 @@ static const struct file_operations dev_mc_seq_fops = {
         .open    = dev_mc_seq_open,
         .read    = seq_read,
         .llseek  = seq_lseek,
-        .release = dev_mc_seq_release,
+        .release = seq_release_net,
 };
 
 #endif
diff --git a/net/netlink/af_netlink.c b/net/netlink/af_netlink.c
index de3988ba1f46..1518244ffad9 100644
--- a/net/netlink/af_netlink.c
+++ b/net/netlink/af_netlink.c
@@ -1681,7 +1681,7 @@ int nlmsg_notify(struct sock *sk, struct sk_buff *skb, u32 pid,
 
 #ifdef CONFIG_PROC_FS
 struct nl_seq_iter {
-        struct net *net;
+        struct seq_net_private p;
         int link;
         int hash_idx;
 };
@@ -1699,7 +1699,7 @@ static struct sock *netlink_seq_socket_idx(struct seq_file *seq, loff_t pos)
 
                 for (j = 0; j <= hash->mask; j++) {
                         sk_for_each(s, node, &hash->table[j]) {
-                                if (iter->net != s->sk_net)
+                                if (iter->p.net != s->sk_net)
                                         continue;
                                 if (off == pos) {
                                         iter->link = i;
@@ -1734,7 +1734,7 @@ static void *netlink_seq_next(struct seq_file *seq, void *v, loff_t *pos)
         s = v;
         do {
                 s = sk_next(s);
-        } while (s && (iter->net != s->sk_net));
+        } while (s && (iter->p.net != s->sk_net));
         if (s)
                 return s;
 
@@ -1746,7 +1746,7 @@ static void *netlink_seq_next(struct seq_file *seq, void *v, loff_t *pos)
 
                 for (; j <= hash->mask; j++) {
                         s = sk_head(&hash->table[j]);
-                        while (s && (iter->net != s->sk_net))
+                        while (s && (iter->p.net != s->sk_net))
                                 s = sk_next(s);
                         if (s) {
                                 iter->link = i;
@@ -1802,27 +1802,8 @@ static const struct seq_operations netlink_seq_ops = {
 
 static int netlink_seq_open(struct inode *inode, struct file *file)
 {
-        struct nl_seq_iter *iter;
-
-        iter = __seq_open_private(file, &netlink_seq_ops, sizeof(*iter));
-        if (!iter)
-                return -ENOMEM;
-
-        iter->net = get_proc_net(inode);
-        if (!iter->net) {
-                seq_release_private(inode, file);
-                return -ENXIO;
-        }
-
-        return 0;
-}
-
-static int netlink_seq_release(struct inode *inode, struct file *file)
-{
-        struct seq_file *seq = file->private_data;
-        struct nl_seq_iter *iter = seq->private;
-        put_net(iter->net);
-        return seq_release_private(inode, file);
+        return seq_open_net(inode, file, &netlink_seq_ops,
+                                sizeof(struct nl_seq_iter));
 }
 
 static const struct file_operations netlink_seq_fops = {
@@ -1830,7 +1811,7 @@ static const struct file_operations netlink_seq_fops = {
         .open           = netlink_seq_open,
         .read           = seq_read,
         .llseek         = seq_lseek,
-        .release        = netlink_seq_release,
+        .release        = seq_release_net,
 };
 
 #endif
diff --git a/net/packet/af_packet.c b/net/packet/af_packet.c
index 45e3cbcb2763..ace29f1c4c5b 100644
--- a/net/packet/af_packet.c
+++ b/net/packet/af_packet.c
@@ -1871,7 +1871,7 @@ static inline struct sock *packet_seq_idx(struct net *net, loff_t off)
 
 static void *packet_seq_start(struct seq_file *seq, loff_t *pos)
 {
-        struct net *net = seq->private;
+        struct net *net = seq_file_net(seq);
         read_lock(&net->packet_sklist_lock);
         return *pos ? packet_seq_idx(net, *pos - 1) : SEQ_START_TOKEN;
 }
@@ -1924,26 +1924,8 @@ static const struct seq_operations packet_seq_ops = {
 
 static int packet_seq_open(struct inode *inode, struct file *file)
 {
-        struct seq_file *seq;
-        int res;
-        res = seq_open(file, &packet_seq_ops);
-        if (!res) {
-                seq = file->private_data;
-                seq->private = get_proc_net(inode);
-                if (!seq->private) {
-                        seq_release(inode, file);
-                        res = -ENXIO;
-                }
-        }
-        return res;
-}
-
-static int packet_seq_release(struct inode *inode, struct file *file)
-{
-        struct seq_file *seq=  file->private_data;
-        struct net *net = seq->private;
-        put_net(net);
-        return seq_release(inode, file);
+        return seq_open_net(inode, file, &packet_seq_ops,
+                            sizeof(struct seq_net_private));
 }
 
 static const struct file_operations packet_seq_fops = {
@@ -1951,7 +1933,7 @@ static const struct file_operations packet_seq_fops = {
         .open           = packet_seq_open,
         .read           = seq_read,
         .llseek         = seq_lseek,
-        .release        = packet_seq_release,
+        .release        = seq_release_net,
 };
 
 #endif
diff --git a/net/unix/af_unix.c b/net/unix/af_unix.c
index ecad42b72ad6..eacddb21a9b4 100644
--- a/net/unix/af_unix.c
+++ b/net/unix/af_unix.c
@@ -2018,7 +2018,7 @@ static unsigned int unix_poll(struct file * file, struct socket *sock, poll_tabl
 
 #ifdef CONFIG_PROC_FS
 struct unix_iter_state {
-        struct net *net;
+        struct seq_net_private p;
         int i;
 };
 static struct sock *unix_seq_idx(struct unix_iter_state *iter, loff_t pos)
@@ -2027,7 +2027,7 @@ static struct sock *unix_seq_idx(struct unix_iter_state *iter, loff_t pos)
         struct sock *s;
 
         for (s = first_unix_socket(&iter->i); s; s = next_unix_socket(&iter->i, s)) {
-                if (s->sk_net != iter->net)
+                if (s->sk_net != iter->p.net)
                         continue;
                 if (off == pos)
                         return s;
@@ -2054,7 +2054,7 @@ static void *unix_seq_next(struct seq_file *seq, void *v, loff_t *pos)
                 sk = first_unix_socket(&iter->i);
         else
                 sk = next_unix_socket(&iter->i, sk);
-        while (sk && (sk->sk_net != iter->net))
+        while (sk && (sk->sk_net != iter->p.net))
                 sk = next_unix_socket(&iter->i, sk);
         return sk;
 }
@@ -2118,27 +2118,8 @@ static const struct seq_operations unix_seq_ops = {
 
 static int unix_seq_open(struct inode *inode, struct file *file)
 {
-        struct unix_iter_state *it;
-
-        it = __seq_open_private(file, &unix_seq_ops,
-                                sizeof(struct unix_iter_state));
-        if (it == NULL)
-                return -ENOMEM;
-
-        it->net = get_proc_net(inode);
-        if (it->net == NULL) {
-                seq_release_private(inode, file);
-                return -ENXIO;
-        }
-        return 0;
-}
-
-static int unix_seq_release(struct inode *inode, struct file *file)
-{
-        struct seq_file *seq = file->private_data;
-        struct unix_iter_state *iter = seq->private;
-        put_net(iter->net);
-        return seq_release_private(inode, file);
+        return seq_open_net(inode, file, &unix_seq_ops,
+                            sizeof(struct unix_iter_state));
 }
 
 static const struct file_operations unix_seq_fops = {
@@ -2146,7 +2127,7 @@ static const struct file_operations unix_seq_fops = {
         .open           = unix_seq_open,
         .read           = seq_read,
         .llseek         = seq_lseek,
-        .release        = unix_seq_release,
+        .release        = seq_release_net,
 };
 
 #endif
diff --git a/net/wireless/wext.c b/net/wireless/wext.c
index db03ed5ce055..1e4cf615f878 100644
--- a/net/wireless/wext.c
+++ b/net/wireless/wext.c
@@ -673,26 +673,8 @@ static const struct seq_operations wireless_seq_ops = {
 
 static int wireless_seq_open(struct inode *inode, struct file *file)
 {
-        struct seq_file *seq;
-        int res;
-        res = seq_open(file, &wireless_seq_ops);
-        if (!res) {
-                seq = file->private_data;
-                seq->private = get_proc_net(inode);
-                if (!seq->private) {
-                        seq_release(inode, file);
-                        res = -ENXIO;
-                }
-        }
-        return res;
-}
-
-static int wireless_seq_release(struct inode *inode, struct file *file)
-{
-        struct seq_file *seq = file->private_data;
-        struct net *net = seq->private;
-        put_net(net);
-        return seq_release(inode, file);
+        return seq_open_net(inode, file, &wireless_seq_ops,
+                            sizeof(struct seq_net_private));
 }
 
 static const struct file_operations wireless_seq_fops = {
@@ -700,7 +682,7 @@ static const struct file_operations wireless_seq_fops = {
         .open    = wireless_seq_open,
         .read    = seq_read,
         .llseek  = seq_lseek,
-        .release = wireless_seq_release,
+        .release = seq_release_net,
 };
 
 int wext_proc_init(struct net *net)