diff options
Diffstat (limited to 'security/selinux/netif.c')
| -rw-r--r-- | security/selinux/netif.c | 123 |
1 files changed, 52 insertions, 71 deletions
diff --git a/security/selinux/netif.c b/security/selinux/netif.c index 694e9e43855f..e24b2cba28ea 100644 --- a/security/selinux/netif.c +++ b/security/selinux/netif.c @@ -1,3 +1,4 @@ +// SPDX-License-Identifier: GPL-2.0-only /* * Network interface table. * @@ -9,10 +10,6 @@ * Copyright (C) 2003 Red Hat, Inc., James Morris <jmorris@redhat.com> * Copyright (C) 2007 Hewlett-Packard Development Company, L.P. * Paul Moore <paul@paul-moore.com> - * - * This program is free software; you can redistribute it and/or modify - * it under the terms of the GNU General Public License version 2, - * as published by the Free Software Foundation. */ #include <linux/init.h> #include <linux/types.h> @@ -25,6 +22,7 @@ #include <linux/rcupdate.h> #include <net/net_namespace.h> +#include "initcalls.h" #include "security.h" #include "objsec.h" #include "netif.h" @@ -39,12 +37,12 @@ struct sel_netif { }; static u32 sel_netif_total; -static LIST_HEAD(sel_netif_list); static DEFINE_SPINLOCK(sel_netif_lock); static struct list_head sel_netif_hash[SEL_NETIF_HASH_SIZE]; /** * sel_netif_hashfn - Hashing function for the interface table + * @ns: the network namespace * @ifindex: the network interface * * Description: @@ -52,13 +50,14 @@ static struct list_head sel_netif_hash[SEL_NETIF_HASH_SIZE]; * bucket number for the given interface. * */ -static inline u32 sel_netif_hashfn(int ifindex) +static inline u32 sel_netif_hashfn(const struct net *ns, int ifindex) { - return (ifindex & (SEL_NETIF_HASH_SIZE - 1)); + return (((uintptr_t)ns + ifindex) & (SEL_NETIF_HASH_SIZE - 1)); } /** * sel_netif_find - Search for an interface record + * @ns: the network namespace * @ifindex: the network interface * * Description: @@ -66,15 +65,15 @@ static inline u32 sel_netif_hashfn(int ifindex) * If an entry can not be found in the table return NULL. * */ -static inline struct sel_netif *sel_netif_find(int ifindex) +static inline struct sel_netif *sel_netif_find(const struct net *ns, + int ifindex) { - int idx = sel_netif_hashfn(ifindex); + u32 idx = sel_netif_hashfn(ns, ifindex); struct sel_netif *netif; list_for_each_entry_rcu(netif, &sel_netif_hash[idx], list) - /* all of the devices should normally fit in the hash, so we - * optimize for that case */ - if (likely(netif->nsec.ifindex == ifindex)) + if (net_eq(netif->nsec.ns, ns) && + netif->nsec.ifindex == ifindex) return netif; return NULL; @@ -91,12 +90,12 @@ static inline struct sel_netif *sel_netif_find(int ifindex) */ static int sel_netif_insert(struct sel_netif *netif) { - int idx; + u32 idx; if (sel_netif_total >= SEL_NETIF_HASH_MAX) return -ENOSPC; - idx = sel_netif_hashfn(netif->nsec.ifindex); + idx = sel_netif_hashfn(netif->nsec.ns, netif->nsec.ifindex); list_add_rcu(&netif->list, &sel_netif_hash[idx]); sel_netif_total++; @@ -120,70 +119,69 @@ static void sel_netif_destroy(struct sel_netif *netif) /** * sel_netif_sid_slow - Lookup the SID of a network interface using the policy + * @ns: the network namespace * @ifindex: the network interface * @sid: interface SID * * Description: - * This function determines the SID of a network interface by quering the + * This function determines the SID of a network interface by querying the * security policy. The result is added to the network interface table to * speedup future queries. Returns zero on success, negative values on * failure. * */ -static int sel_netif_sid_slow(int ifindex, u32 *sid) +static int sel_netif_sid_slow(struct net *ns, int ifindex, u32 *sid) { - int ret; + int ret = 0; struct sel_netif *netif; - struct sel_netif *new = NULL; + struct sel_netif *new; struct net_device *dev; /* NOTE: we always use init's network namespace since we don't * currently support containers */ - dev = dev_get_by_index(&init_net, ifindex); + dev = dev_get_by_index(ns, ifindex); if (unlikely(dev == NULL)) { - printk(KERN_WARNING - "SELinux: failure in sel_netif_sid_slow()," - " invalid network interface (%d)\n", ifindex); + pr_warn("SELinux: failure in %s(), invalid network interface (%d)\n", + __func__, ifindex); return -ENOENT; } spin_lock_bh(&sel_netif_lock); - netif = sel_netif_find(ifindex); + netif = sel_netif_find(ns, ifindex); if (netif != NULL) { *sid = netif->nsec.sid; - ret = 0; goto out; } - new = kzalloc(sizeof(*new), GFP_ATOMIC); - if (new == NULL) { - ret = -ENOMEM; - goto out; - } - ret = security_netif_sid(dev->name, &new->nsec.sid); - if (ret != 0) - goto out; - new->nsec.ifindex = ifindex; - ret = sel_netif_insert(new); + + ret = security_netif_sid(dev->name, sid); if (ret != 0) goto out; - *sid = new->nsec.sid; + + /* If this memory allocation fails still return 0. The SID + * is valid, it just won't be added to the cache. + */ + new = kmalloc(sizeof(*new), GFP_ATOMIC); + if (new) { + new->nsec.ns = ns; + new->nsec.ifindex = ifindex; + new->nsec.sid = *sid; + if (sel_netif_insert(new)) + kfree(new); + } out: spin_unlock_bh(&sel_netif_lock); dev_put(dev); - if (unlikely(ret)) { - printk(KERN_WARNING - "SELinux: failure in sel_netif_sid_slow()," - " unable to determine network interface label (%d)\n", - ifindex); - kfree(new); - } + if (unlikely(ret)) + pr_warn("SELinux: failure in %s(), unable to determine network interface label (%d)\n", + __func__, ifindex); return ret; } /** * sel_netif_sid - Lookup the SID of a network interface + * @ns: the network namespace * @ifindex: the network interface * @sid: interface SID * @@ -195,12 +193,12 @@ out: * on failure. * */ -int sel_netif_sid(int ifindex, u32 *sid) +int sel_netif_sid(struct net *ns, int ifindex, u32 *sid) { struct sel_netif *netif; rcu_read_lock(); - netif = sel_netif_find(ifindex); + netif = sel_netif_find(ns, ifindex); if (likely(netif != NULL)) { *sid = netif->nsec.sid; rcu_read_unlock(); @@ -208,11 +206,12 @@ int sel_netif_sid(int ifindex, u32 *sid) } rcu_read_unlock(); - return sel_netif_sid_slow(ifindex, sid); + return sel_netif_sid_slow(ns, ifindex, sid); } /** * sel_netif_kill - Remove an entry from the network interface table + * @ns: the network namespace * @ifindex: the network interface * * Description: @@ -220,13 +219,13 @@ int sel_netif_sid(int ifindex, u32 *sid) * table if it exists. * */ -static void sel_netif_kill(int ifindex) +static void sel_netif_kill(const struct net *ns, int ifindex) { struct sel_netif *netif; rcu_read_lock(); spin_lock_bh(&sel_netif_lock); - netif = sel_netif_find(ifindex); + netif = sel_netif_find(ns, ifindex); if (netif) sel_netif_destroy(netif); spin_unlock_bh(&sel_netif_lock); @@ -240,7 +239,7 @@ static void sel_netif_kill(int ifindex) * Remove all entries from the network interface table. * */ -static void sel_netif_flush(void) +void sel_netif_flush(void) { int idx; struct sel_netif *netif; @@ -252,25 +251,13 @@ static void sel_netif_flush(void) spin_unlock_bh(&sel_netif_lock); } -static int sel_netif_avc_callback(u32 event) -{ - if (event == AVC_CALLBACK_RESET) { - sel_netif_flush(); - synchronize_net(); - } - return 0; -} - static int sel_netif_netdev_notifier_handler(struct notifier_block *this, unsigned long event, void *ptr) { struct net_device *dev = netdev_notifier_info_to_dev(ptr); - if (dev_net(dev) != &init_net) - return NOTIFY_DONE; - if (event == NETDEV_DOWN) - sel_netif_kill(dev->ifindex); + sel_netif_kill(dev_net(dev), dev->ifindex); return NOTIFY_DONE; } @@ -279,11 +266,11 @@ static struct notifier_block sel_netif_netdev_notifier = { .notifier_call = sel_netif_netdev_notifier_handler, }; -static __init int sel_netif_init(void) +int __init sel_netif_init(void) { - int i, err; + int i; - if (!selinux_enabled) + if (!selinux_enabled_boot) return 0; for (i = 0; i < SEL_NETIF_HASH_SIZE; i++) @@ -291,12 +278,6 @@ static __init int sel_netif_init(void) register_netdevice_notifier(&sel_netif_netdev_notifier); - err = avc_add_callback(sel_netif_avc_callback, AVC_CALLBACK_RESET); - if (err) - panic("avc_add_callback() failed, error %d\n", err); - - return err; + return 0; } -__initcall(sel_netif_init); - |