diff options
Diffstat (limited to 'lib/kobject_uevent.c')
| -rw-r--r-- | lib/kobject_uevent.c | 178 |
1 files changed, 126 insertions, 52 deletions
diff --git a/lib/kobject_uevent.c b/lib/kobject_uevent.c index 15ea216a67ce6..63d0816ab23b0 100644 --- a/lib/kobject_uevent.c +++ b/lib/kobject_uevent.c @@ -22,6 +22,7 @@ #include <linux/socket.h> #include <linux/skbuff.h> #include <linux/netlink.h> +#include <linux/uidgid.h> #include <linux/uuid.h> #include <linux/ctype.h> #include <net/sock.h> @@ -231,30 +232,6 @@ out: return r; } -#ifdef CONFIG_NET -static int kobj_bcast_filter(struct sock *dsk, struct sk_buff *skb, void *data) -{ - struct kobject *kobj = data, *ksobj; - const struct kobj_ns_type_operations *ops; - - ops = kobj_ns_ops(kobj); - if (!ops && kobj->kset) { - ksobj = &kobj->kset->kobj; - if (ksobj->parent != NULL) - ops = kobj_ns_ops(ksobj->parent); - } - - if (ops && ops->netlink_ns && kobj->ktype->namespace) { - const void *sock_ns, *ns; - ns = kobj->ktype->namespace(kobj); - sock_ns = ops->netlink_ns(dsk); - return sock_ns != ns; - } - - return 0; -} -#endif - #ifdef CONFIG_UEVENT_HELPER static int kobj_usermode_filter(struct kobject *kobj) { @@ -296,15 +273,44 @@ static void cleanup_uevent_env(struct subprocess_info *info) } #endif -static int kobject_uevent_net_broadcast(struct kobject *kobj, - struct kobj_uevent_env *env, +#ifdef CONFIG_NET +static struct sk_buff *alloc_uevent_skb(struct kobj_uevent_env *env, const char *action_string, const char *devpath) { - int retval = 0; -#if defined(CONFIG_NET) + struct netlink_skb_parms *parms; + struct sk_buff *skb = NULL; + char *scratch; + size_t len; + + /* allocate message with maximum possible size */ + len = strlen(action_string) + strlen(devpath) + 2; + skb = alloc_skb(len + env->buflen, GFP_KERNEL); + if (!skb) + return NULL; + + /* add header */ + scratch = skb_put(skb, len); + sprintf(scratch, "%s@%s", action_string, devpath); + + skb_put_data(skb, env->buf, env->buflen); + + parms = &NETLINK_CB(skb); + parms->creds.uid = GLOBAL_ROOT_UID; + parms->creds.gid = GLOBAL_ROOT_GID; + parms->dst_group = 1; + parms->portid = 0; + + return skb; +} + +static int uevent_net_broadcast_untagged(struct kobj_uevent_env *env, + const char *action_string, + const char *devpath) +{ struct sk_buff *skb = NULL; struct uevent_sock *ue_sk; + int retval = 0; /* send netlink message */ list_for_each_entry(ue_sk, &uevent_sock_list, list) { @@ -314,37 +320,99 @@ static int kobject_uevent_net_broadcast(struct kobject *kobj, continue; if (!skb) { - /* allocate message with the maximum possible size */ - size_t len = strlen(action_string) + strlen(devpath) + 2; - char *scratch; - retval = -ENOMEM; - skb = alloc_skb(len + env->buflen, GFP_KERNEL); + skb = alloc_uevent_skb(env, action_string, devpath); if (!skb) continue; - - /* add header */ - scratch = skb_put(skb, len); - sprintf(scratch, "%s@%s", action_string, devpath); - - skb_put_data(skb, env->buf, env->buflen); - - NETLINK_CB(skb).dst_group = 1; } - retval = netlink_broadcast_filtered(uevent_sock, skb_get(skb), - 0, 1, GFP_KERNEL, - kobj_bcast_filter, - kobj); + retval = netlink_broadcast(uevent_sock, skb_get(skb), 0, 1, + GFP_KERNEL); /* ENOBUFS should be handled in userspace */ if (retval == -ENOBUFS || retval == -ESRCH) retval = 0; } consume_skb(skb); -#endif + return retval; } +static int uevent_net_broadcast_tagged(struct sock *usk, + struct kobj_uevent_env *env, + const char *action_string, + const char *devpath) +{ + struct user_namespace *owning_user_ns = sock_net(usk)->user_ns; + struct sk_buff *skb = NULL; + int ret = 0; + + skb = alloc_uevent_skb(env, action_string, devpath); + if (!skb) + return -ENOMEM; + + /* fix credentials */ + if (owning_user_ns != &init_user_ns) { + struct netlink_skb_parms *parms = &NETLINK_CB(skb); + kuid_t root_uid; + kgid_t root_gid; + + /* fix uid */ + root_uid = make_kuid(owning_user_ns, 0); + if (uid_valid(root_uid)) + parms->creds.uid = root_uid; + + /* fix gid */ + root_gid = make_kgid(owning_user_ns, 0); + if (gid_valid(root_gid)) + parms->creds.gid = root_gid; + } + + ret = netlink_broadcast(usk, skb, 0, 1, GFP_KERNEL); + /* ENOBUFS should be handled in userspace */ + if (ret == -ENOBUFS || ret == -ESRCH) + ret = 0; + + return ret; +} +#endif + +static int kobject_uevent_net_broadcast(struct kobject *kobj, + struct kobj_uevent_env *env, + const char *action_string, + const char *devpath) +{ + int ret = 0; + +#ifdef CONFIG_NET + const struct kobj_ns_type_operations *ops; + const struct net *net = NULL; + + ops = kobj_ns_ops(kobj); + if (!ops && kobj->kset) { + struct kobject *ksobj = &kobj->kset->kobj; + if (ksobj->parent != NULL) + ops = kobj_ns_ops(ksobj->parent); + } + + /* kobjects currently only carry network namespace tags and they + * are the only tag relevant here since we want to decide which + * network namespaces to broadcast the uevent into. + */ + if (ops && ops->netlink_ns && kobj->ktype->namespace) + if (ops->type == KOBJ_NS_TYPE_NET) + net = kobj->ktype->namespace(kobj); + + if (!net) + ret = uevent_net_broadcast_untagged(env, action_string, + devpath); + else + ret = uevent_net_broadcast_tagged(net->uevent_sock->sk, env, + action_string, devpath); +#endif + + return ret; +} + static void zap_modalias_env(struct kobj_uevent_env *env) { static const char modalias_prefix[] = "MODALIAS="; @@ -703,9 +771,13 @@ static int uevent_net_init(struct net *net) net->uevent_sock = ue_sk; - mutex_lock(&uevent_sock_mutex); - list_add_tail(&ue_sk->list, &uevent_sock_list); - mutex_unlock(&uevent_sock_mutex); + /* Restrict uevents to initial user namespace. */ + if (sock_net(ue_sk->sk)->user_ns == &init_user_ns) { + mutex_lock(&uevent_sock_mutex); + list_add_tail(&ue_sk->list, &uevent_sock_list); + mutex_unlock(&uevent_sock_mutex); + } + return 0; } @@ -713,9 +785,11 @@ static void uevent_net_exit(struct net *net) { struct uevent_sock *ue_sk = net->uevent_sock; - mutex_lock(&uevent_sock_mutex); - list_del(&ue_sk->list); - mutex_unlock(&uevent_sock_mutex); + if (sock_net(ue_sk->sk)->user_ns == &init_user_ns) { + mutex_lock(&uevent_sock_mutex); + list_del(&ue_sk->list); + mutex_unlock(&uevent_sock_mutex); + } netlink_kernel_release(ue_sk->sk); kfree(ue_sk); |