diff options
Diffstat (limited to 'lib/kobject_uevent.c')
-rw-r--r-- | lib/kobject_uevent.c | 119 |
1 files changed, 104 insertions, 15 deletions
diff --git a/lib/kobject_uevent.c b/lib/kobject_uevent.c index 920a3ca6e259..70af0a7f97c0 100644 --- a/lib/kobject_uevent.c +++ b/lib/kobject_uevent.c @@ -18,18 +18,25 @@ #include <linux/string.h> #include <linux/kobject.h> #include <linux/module.h> - +#include <linux/slab.h> +#include <linux/user_namespace.h> #include <linux/socket.h> #include <linux/skbuff.h> #include <linux/netlink.h> #include <net/sock.h> +#include <net/net_namespace.h> u64 uevent_seqnum; char uevent_helper[UEVENT_HELPER_PATH_LEN] = CONFIG_UEVENT_HELPER_PATH; static DEFINE_SPINLOCK(sequence_lock); -#if defined(CONFIG_NET) -static struct sock *uevent_sock; +#ifdef CONFIG_NET +struct uevent_sock { + struct list_head list; + struct sock *sk; +}; +static LIST_HEAD(uevent_sock_list); +static DEFINE_MUTEX(uevent_sock_mutex); #endif /* the strings here must match the enum in include/linux/kobject.h */ @@ -76,6 +83,39 @@ out: return ret; } +#ifdef CONFIG_NET +static int kobj_bcast_filter(struct sock *dsk, struct sk_buff *skb, void *data) +{ + struct kobject *kobj = data; + const struct kobj_ns_type_operations *ops; + + ops = kobj_ns_ops(kobj); + if (ops) { + const void *sock_ns, *ns; + ns = kobj->ktype->namespace(kobj); + sock_ns = ops->netlink_ns(dsk); + return sock_ns != ns; + } + + return 0; +} +#endif + +static int kobj_usermode_filter(struct kobject *kobj) +{ + const struct kobj_ns_type_operations *ops; + + ops = kobj_ns_ops(kobj); + if (ops) { + const void *init_ns, *ns; + ns = kobj->ktype->namespace(kobj); + init_ns = ops->initial_ns(); + return ns != init_ns; + } + + return 0; +} + /** * kobject_uevent_env - send an uevent with environmental data * @@ -83,7 +123,7 @@ out: * @kobj: struct kobject that the action is happening to * @envp_ext: pointer to environmental data * - * Returns 0 if kobject_uevent() is completed with success or the + * Returns 0 if kobject_uevent_env() is completed with success or the * corresponding error when it fails. */ int kobject_uevent_env(struct kobject *kobj, enum kobject_action action, @@ -95,10 +135,13 @@ int kobject_uevent_env(struct kobject *kobj, enum kobject_action action, const char *subsystem; struct kobject *top_kobj; struct kset *kset; - struct kset_uevent_ops *uevent_ops; + const struct kset_uevent_ops *uevent_ops; u64 seq; int i = 0; int retval = 0; +#ifdef CONFIG_NET + struct uevent_sock *ue_sk; +#endif pr_debug("kobject: '%s' (%p): %s\n", kobject_name(kobj), kobj, __func__); @@ -210,7 +253,9 @@ int kobject_uevent_env(struct kobject *kobj, enum kobject_action action, #if defined(CONFIG_NET) /* send netlink message */ - if (uevent_sock) { + mutex_lock(&uevent_sock_mutex); + list_for_each_entry(ue_sk, &uevent_sock_list, list) { + struct sock *uevent_sock = ue_sk->sk; struct sk_buff *skb; size_t len; @@ -232,18 +277,21 @@ int kobject_uevent_env(struct kobject *kobj, enum kobject_action action, } NETLINK_CB(skb).dst_group = 1; - retval = netlink_broadcast(uevent_sock, skb, 0, 1, - GFP_KERNEL); + retval = netlink_broadcast_filtered(uevent_sock, skb, + 0, 1, GFP_KERNEL, + kobj_bcast_filter, + kobj); /* ENOBUFS should be handled in userspace */ if (retval == -ENOBUFS) retval = 0; } else retval = -ENOMEM; } + mutex_unlock(&uevent_sock_mutex); #endif /* call uevent_helper, usually only enabled during early boot */ - if (uevent_helper[0]) { + if (uevent_helper[0] && !kobj_usermode_filter(kobj)) { char *argv [3]; argv [0] = uevent_helper; @@ -269,7 +317,7 @@ exit: EXPORT_SYMBOL_GPL(kobject_uevent_env); /** - * kobject_uevent - notify userspace by ending an uevent + * kobject_uevent - notify userspace by sending an uevent * * @action: action that is happening * @kobj: struct kobject that the action is happening to @@ -319,18 +367,59 @@ int add_uevent_var(struct kobj_uevent_env *env, const char *format, ...) EXPORT_SYMBOL_GPL(add_uevent_var); #if defined(CONFIG_NET) -static int __init kobject_uevent_init(void) +static int uevent_net_init(struct net *net) { - uevent_sock = netlink_kernel_create(&init_net, NETLINK_KOBJECT_UEVENT, - 1, NULL, NULL, THIS_MODULE); - if (!uevent_sock) { + struct uevent_sock *ue_sk; + + ue_sk = kzalloc(sizeof(*ue_sk), GFP_KERNEL); + if (!ue_sk) + return -ENOMEM; + + ue_sk->sk = netlink_kernel_create(net, NETLINK_KOBJECT_UEVENT, + 1, NULL, NULL, THIS_MODULE); + if (!ue_sk->sk) { printk(KERN_ERR "kobject_uevent: unable to create netlink socket!\n"); + kfree(ue_sk); return -ENODEV; } - netlink_set_nonroot(NETLINK_KOBJECT_UEVENT, NL_NONROOT_RECV); + mutex_lock(&uevent_sock_mutex); + list_add_tail(&ue_sk->list, &uevent_sock_list); + mutex_unlock(&uevent_sock_mutex); return 0; } +static void uevent_net_exit(struct net *net) +{ + struct uevent_sock *ue_sk; + + mutex_lock(&uevent_sock_mutex); + list_for_each_entry(ue_sk, &uevent_sock_list, list) { + if (sock_net(ue_sk->sk) == net) + goto found; + } + mutex_unlock(&uevent_sock_mutex); + return; + +found: + list_del(&ue_sk->list); + mutex_unlock(&uevent_sock_mutex); + + netlink_kernel_release(ue_sk->sk); + kfree(ue_sk); +} + +static struct pernet_operations uevent_net_ops = { + .init = uevent_net_init, + .exit = uevent_net_exit, +}; + +static int __init kobject_uevent_init(void) +{ + netlink_set_nonroot(NETLINK_KOBJECT_UEVENT, NL_NONROOT_RECV); + return register_pernet_subsys(&uevent_net_ops); +} + + postcore_initcall(kobject_uevent_init); #endif |