can: initial support for network namespaces

This patch adds initial support for network namespaces. The changes only
enable support in the CAN raw, proc and af_can code. GW and BCM still
have their checks that ensure that they are used only from the main
namespace.

The patch boils down to moving the global structures, i.e. the global
filter list and their /proc stats, into a per-namespace structure and passing
around the corresponding "struct net" in a lot of different places.

Changes since v1:
 - rebased on current HEAD (2bfe01e)
 - fixed overlong line

Signed-off-by: Mario Kicherer <dev@kicherer.org>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

1 files changed, 70 insertions, 74 deletions

diff --git a/net/can/proc.c b/net/can/proc.c
index 85ef7bb0f176..9a8d54d57b22 100644
--- a/net/can/proc.c
+++ b/net/can/proc.c
@@ -62,17 +62,6 @@
 #define CAN_PROC_RCVLIST_EFF "rcvlist_eff"
 #define CAN_PROC_RCVLIST_ERR "rcvlist_err"
 
-static struct proc_dir_entry *can_dir;
-static struct proc_dir_entry *pde_version;
-static struct proc_dir_entry *pde_stats;
-static struct proc_dir_entry *pde_reset_stats;
-static struct proc_dir_entry *pde_rcvlist_all;
-static struct proc_dir_entry *pde_rcvlist_fil;
-static struct proc_dir_entry *pde_rcvlist_inv;
-static struct proc_dir_entry *pde_rcvlist_sff;
-static struct proc_dir_entry *pde_rcvlist_eff;
-static struct proc_dir_entry *pde_rcvlist_err;
-
 static int user_reset;
 
 static const char rx_list_name[][8] = {
@@ -351,20 +340,21 @@ static inline void can_rcvlist_proc_show_one(struct seq_file *m, int idx,
 static int can_rcvlist_proc_show(struct seq_file *m, void *v)
 {
 	/* double cast to prevent GCC warning */
-	int idx = (int)(long)m->private;
+	int idx = (int)(long)PDE_DATA(m->file->f_inode);
 	struct net_device *dev;
 	struct dev_rcv_lists *d;
+	struct net *net = m->private;
 
 	seq_printf(m, "\nreceive list '%s':\n", rx_list_name[idx]);
 
 	rcu_read_lock();
 
 	/* receive list for 'all' CAN devices (dev == NULL) */
-	d = &can_rx_alldev_list;
+	d = net->can.can_rx_alldev_list;
 	can_rcvlist_proc_show_one(m, idx, NULL, d);
 
 	/* receive list for registered CAN devices */
-	for_each_netdev_rcu(&init_net, dev) {
+	for_each_netdev_rcu(net, dev) {
 		if (dev->type == ARPHRD_CAN && dev->ml_priv)
 			can_rcvlist_proc_show_one(m, idx, dev, dev->ml_priv);
 	}
@@ -377,7 +367,7 @@ static int can_rcvlist_proc_show(struct seq_file *m, void *v)
 
 static int can_rcvlist_proc_open(struct inode *inode, struct file *file)
 {
-	return single_open(file, can_rcvlist_proc_show, PDE_DATA(inode));
+	return single_open_net(inode, file, can_rcvlist_proc_show);
 }
 
 static const struct file_operations can_rcvlist_proc_fops = {
@@ -417,6 +407,7 @@ static int can_rcvlist_sff_proc_show(struct seq_file *m, void *v)
 {
 	struct net_device *dev;
 	struct dev_rcv_lists *d;
+	struct net *net = m->private;
 
 	/* RX_SFF */
 	seq_puts(m, "\nreceive list 'rx_sff':\n");
@@ -424,11 +415,11 @@ static int can_rcvlist_sff_proc_show(struct seq_file *m, void *v)
 	rcu_read_lock();
 
 	/* sff receive list for 'all' CAN devices (dev == NULL) */
-	d = &can_rx_alldev_list;
+	d = net->can.can_rx_alldev_list;
 	can_rcvlist_proc_show_array(m, NULL, d->rx_sff, ARRAY_SIZE(d->rx_sff));
 
 	/* sff receive list for registered CAN devices */
-	for_each_netdev_rcu(&init_net, dev) {
+	for_each_netdev_rcu(net, dev) {
 		if (dev->type == ARPHRD_CAN && dev->ml_priv) {
 			d = dev->ml_priv;
 			can_rcvlist_proc_show_array(m, dev, d->rx_sff,
@@ -444,7 +435,7 @@ static int can_rcvlist_sff_proc_show(struct seq_file *m, void *v)
 
 static int can_rcvlist_sff_proc_open(struct inode *inode, struct file *file)
 {
-	return single_open(file, can_rcvlist_sff_proc_show, NULL);
+	return single_open_net(inode, file, can_rcvlist_sff_proc_show);
 }
 
 static const struct file_operations can_rcvlist_sff_proc_fops = {
@@ -460,6 +451,7 @@ static int can_rcvlist_eff_proc_show(struct seq_file *m, void *v)
 {
 	struct net_device *dev;
 	struct dev_rcv_lists *d;
+	struct net *net = m->private;
 
 	/* RX_EFF */
 	seq_puts(m, "\nreceive list 'rx_eff':\n");
@@ -467,11 +459,11 @@ static int can_rcvlist_eff_proc_show(struct seq_file *m, void *v)
 	rcu_read_lock();
 
 	/* eff receive list for 'all' CAN devices (dev == NULL) */
-	d = &can_rx_alldev_list;
+	d = net->can.can_rx_alldev_list;
 	can_rcvlist_proc_show_array(m, NULL, d->rx_eff, ARRAY_SIZE(d->rx_eff));
 
 	/* eff receive list for registered CAN devices */
-	for_each_netdev_rcu(&init_net, dev) {
+	for_each_netdev_rcu(net, dev) {
 		if (dev->type == ARPHRD_CAN && dev->ml_priv) {
 			d = dev->ml_priv;
 			can_rcvlist_proc_show_array(m, dev, d->rx_eff,
@@ -487,7 +479,7 @@ static int can_rcvlist_eff_proc_show(struct seq_file *m, void *v)
 
 static int can_rcvlist_eff_proc_open(struct inode *inode, struct file *file)
 {
-	return single_open(file, can_rcvlist_eff_proc_show, NULL);
+	return single_open_net(inode, file, can_rcvlist_eff_proc_show);
 }
 
 static const struct file_operations can_rcvlist_eff_proc_fops = {
@@ -499,81 +491,85 @@ static const struct file_operations can_rcvlist_eff_proc_fops = {
 };
 
 /*
- * proc utility functions
- */
-
-static void can_remove_proc_readentry(const char *name)
-{
-	if (can_dir)
-		remove_proc_entry(name, can_dir);
-}
-
-/*
  * can_init_proc - create main CAN proc directory and procfs entries
  */
-void can_init_proc(void)
+void can_init_proc(struct net *net)
 {
 	/* create /proc/net/can directory */
-	can_dir = proc_mkdir("can", init_net.proc_net);
+	net->can.proc_dir = proc_net_mkdir(net, "can", net->proc_net);
 
-	if (!can_dir) {
-		pr_info("can: failed to create /proc/net/can.\n");
+	if (!net->can.proc_dir) {
+		printk(KERN_INFO "can: failed to create /proc/net/can . "
+			   "CONFIG_PROC_FS missing?\n");
 		return;
 	}
 
 	/* own procfs entries from the AF_CAN core */
-	pde_version     = proc_create(CAN_PROC_VERSION, 0644, can_dir,
-				      &can_version_proc_fops);
-	pde_stats       = proc_create(CAN_PROC_STATS, 0644, can_dir,
-				      &can_stats_proc_fops);
-	pde_reset_stats = proc_create(CAN_PROC_RESET_STATS, 0644, can_dir,
-				      &can_reset_stats_proc_fops);
-	pde_rcvlist_err = proc_create_data(CAN_PROC_RCVLIST_ERR, 0644, can_dir,
-					   &can_rcvlist_proc_fops, (void *)RX_ERR);
-	pde_rcvlist_all = proc_create_data(CAN_PROC_RCVLIST_ALL, 0644, can_dir,
-					   &can_rcvlist_proc_fops, (void *)RX_ALL);
-	pde_rcvlist_fil = proc_create_data(CAN_PROC_RCVLIST_FIL, 0644, can_dir,
-					   &can_rcvlist_proc_fops, (void *)RX_FIL);
-	pde_rcvlist_inv = proc_create_data(CAN_PROC_RCVLIST_INV, 0644, can_dir,
-					   &can_rcvlist_proc_fops, (void *)RX_INV);
-	pde_rcvlist_eff = proc_create(CAN_PROC_RCVLIST_EFF, 0644, can_dir,
-				      &can_rcvlist_eff_proc_fops);
-	pde_rcvlist_sff = proc_create(CAN_PROC_RCVLIST_SFF, 0644, can_dir,
-				      &can_rcvlist_sff_proc_fops);
+	net->can.pde_version     = proc_create(CAN_PROC_VERSION, 0644,
+					       net->can.proc_dir,
+					       &can_version_proc_fops);
+	net->can.pde_stats       = proc_create(CAN_PROC_STATS, 0644,
+					       net->can.proc_dir,
+					       &can_stats_proc_fops);
+	net->can.pde_reset_stats = proc_create(CAN_PROC_RESET_STATS, 0644,
+					       net->can.proc_dir,
+					       &can_reset_stats_proc_fops);
+	net->can.pde_rcvlist_err = proc_create_data(CAN_PROC_RCVLIST_ERR, 0644,
+						    net->can.proc_dir,
+						    &can_rcvlist_proc_fops,
+						    (void *)RX_ERR);
+	net->can.pde_rcvlist_all = proc_create_data(CAN_PROC_RCVLIST_ALL, 0644,
+						    net->can.proc_dir,
+						    &can_rcvlist_proc_fops,
+						    (void *)RX_ALL);
+	net->can.pde_rcvlist_fil = proc_create_data(CAN_PROC_RCVLIST_FIL, 0644,
+						    net->can.proc_dir,
+						    &can_rcvlist_proc_fops,
+						    (void *)RX_FIL);
+	net->can.pde_rcvlist_inv = proc_create_data(CAN_PROC_RCVLIST_INV, 0644,
+						    net->can.proc_dir,
+						    &can_rcvlist_proc_fops,
+						    (void *)RX_INV);
+	net->can.pde_rcvlist_eff = proc_create(CAN_PROC_RCVLIST_EFF, 0644,
+					       net->can.proc_dir,
+					       &can_rcvlist_eff_proc_fops);
+	net->can.pde_rcvlist_sff = proc_create(CAN_PROC_RCVLIST_SFF, 0644,
+					       net->can.proc_dir,
+					       &can_rcvlist_sff_proc_fops);
 }
 
 /*
  * can_remove_proc - remove procfs entries and main CAN proc directory
  */
-void can_remove_proc(void)
+void can_remove_proc(struct net *net)
 {
-	if (pde_version)
-		can_remove_proc_readentry(CAN_PROC_VERSION);
+	if (net->can.pde_version)
+		remove_proc_entry(CAN_PROC_VERSION, net->can.proc_dir);
 
-	if (pde_stats)
-		can_remove_proc_readentry(CAN_PROC_STATS);
+	if (net->can.pde_stats)
+		remove_proc_entry(CAN_PROC_STATS, net->can.proc_dir);
 
-	if (pde_reset_stats)
-		can_remove_proc_readentry(CAN_PROC_RESET_STATS);
+	if (net->can.pde_reset_stats)
+		remove_proc_entry(CAN_PROC_RESET_STATS, net->can.proc_dir);
 
-	if (pde_rcvlist_err)
-		can_remove_proc_readentry(CAN_PROC_RCVLIST_ERR);
+	if (net->can.pde_rcvlist_err)
+		remove_proc_entry(CAN_PROC_RCVLIST_ERR, net->can.proc_dir);
 
-	if (pde_rcvlist_all)
-		can_remove_proc_readentry(CAN_PROC_RCVLIST_ALL);
+	if (net->can.pde_rcvlist_all)
+		remove_proc_entry(CAN_PROC_RCVLIST_ALL, net->can.proc_dir);
 
-	if (pde_rcvlist_fil)
-		can_remove_proc_readentry(CAN_PROC_RCVLIST_FIL);
+	if (net->can.pde_rcvlist_fil)
+		remove_proc_entry(CAN_PROC_RCVLIST_FIL, net->can.proc_dir);
 
-	if (pde_rcvlist_inv)
-		can_remove_proc_readentry(CAN_PROC_RCVLIST_INV);
+	if (net->can.pde_rcvlist_inv)
+		remove_proc_entry(CAN_PROC_RCVLIST_INV, net->can.proc_dir);
 
-	if (pde_rcvlist_eff)
-		can_remove_proc_readentry(CAN_PROC_RCVLIST_EFF);
+	if (net->can.pde_rcvlist_eff)
+		remove_proc_entry(CAN_PROC_RCVLIST_EFF, net->can.proc_dir);
 
-	if (pde_rcvlist_sff)
-		can_remove_proc_readentry(CAN_PROC_RCVLIST_SFF);
+	if (net->can.pde_rcvlist_sff)
+		remove_proc_entry(CAN_PROC_RCVLIST_SFF, net->can.proc_dir);
 
-	if (can_dir)
-		remove_proc_entry("can", init_net.proc_net);
+	if (net->can.proc_dir)
+		remove_proc_entry("can", net->proc_net);
 }