[PATCH net-next v3 8/8] bridge: make sure objects belong to container's owner

From: Tyler Hicks
Date: Fri Jul 20 2018 - 17:57:54 EST


When creating various bridge objects in /sys/class/net/... make sure
that they belong to the container's owner instead of global root (if
they belong to a container/namespace).

Signed-off-by: Tyler Hicks <tyhicks@xxxxxxxxxxxxx>
---
net/bridge/br_if.c | 9 +++++++++
net/bridge/br_private.h | 2 ++
net/bridge/br_sysfs_if.c | 5 ++---
3 files changed, 13 insertions(+), 3 deletions(-)

diff --git a/net/bridge/br_if.c b/net/bridge/br_if.c
index 05e42d86882d..e7c8d55212aa 100644
--- a/net/bridge/br_if.c
+++ b/net/bridge/br_if.c
@@ -26,6 +26,7 @@
#include <net/sock.h>
#include <linux/if_vlan.h>
#include <net/switchdev.h>
+#include <net/net_namespace.h>

#include "br_private.h"

@@ -204,11 +205,19 @@ static void release_nbp(struct kobject *kobj)
kfree(p);
}

+static void brport_get_ownership(struct kobject *kobj, kuid_t *uid, kgid_t *gid)
+{
+ struct net_bridge_port *p = kobj_to_brport(kobj);
+
+ net_ns_get_ownership(dev_net(p->dev), uid, gid);
+}
+
static struct kobj_type brport_ktype = {
#ifdef CONFIG_SYSFS
.sysfs_ops = &brport_sysfs_ops,
#endif
.release = release_nbp,
+ .get_ownership = brport_get_ownership,
};

static void destroy_nbp(struct net_bridge_port *p)
diff --git a/net/bridge/br_private.h b/net/bridge/br_private.h
index 5216a524b537..cf0005d2a4d0 100644
--- a/net/bridge/br_private.h
+++ b/net/bridge/br_private.h
@@ -283,6 +283,8 @@ struct net_bridge_port {
u16 group_fwd_mask;
};

+#define kobj_to_brport(obj) container_of(obj, struct net_bridge_port, kobj)
+
#define br_auto_port(p) ((p)->flags & BR_AUTO_MASK)
#define br_promisc_port(p) ((p)->flags & BR_PROMISC)

diff --git a/net/bridge/br_sysfs_if.c b/net/bridge/br_sysfs_if.c
index f99c5bf5c906..ab4c7f8adf68 100644
--- a/net/bridge/br_sysfs_if.c
+++ b/net/bridge/br_sysfs_if.c
@@ -249,13 +249,12 @@ static const struct brport_attribute *brport_attrs[] = {
};

#define to_brport_attr(_at) container_of(_at, struct brport_attribute, attr)
-#define to_brport(obj) container_of(obj, struct net_bridge_port, kobj)

static ssize_t brport_show(struct kobject *kobj,
struct attribute *attr, char *buf)
{
struct brport_attribute *brport_attr = to_brport_attr(attr);
- struct net_bridge_port *p = to_brport(kobj);
+ struct net_bridge_port *p = kobj_to_brport(kobj);

if (!brport_attr->show)
return -EINVAL;
@@ -268,7 +267,7 @@ static ssize_t brport_store(struct kobject *kobj,
const char *buf, size_t count)
{
struct brport_attribute *brport_attr = to_brport_attr(attr);
- struct net_bridge_port *p = to_brport(kobj);
+ struct net_bridge_port *p = kobj_to_brport(kobj);
ssize_t ret = -EINVAL;
char *endp;
unsigned long val;
--
2.7.4