diff options
Diffstat (limited to 'net/netlabel')
| -rw-r--r-- | net/netlabel/netlabel_domainhash.c | 28 | ||||
| -rw-r--r-- | net/netlabel/netlabel_unlabeled.c | 66 |
2 files changed, 37 insertions, 57 deletions
diff --git a/net/netlabel/netlabel_domainhash.c b/net/netlabel/netlabel_domainhash.c index 0bfeaab88ef5..06ab41b6b57a 100644 --- a/net/netlabel/netlabel_domainhash.c +++ b/net/netlabel/netlabel_domainhash.c @@ -50,9 +50,12 @@ struct netlbl_domhsh_tbl { }; /* Domain hash table */ -/* XXX - updates should be so rare that having one spinlock for the entire - * hash table should be okay */ +/* updates should be so rare that having one spinlock for the entire hash table + * should be okay */ static DEFINE_SPINLOCK(netlbl_domhsh_lock); +#define netlbl_domhsh_rcu_deref(p) \ + rcu_dereference_check(p, rcu_read_lock_held() || \ + lockdep_is_held(&netlbl_domhsh_lock)) static struct netlbl_domhsh_tbl *netlbl_domhsh = NULL; static struct netlbl_dom_map *netlbl_domhsh_def = NULL; @@ -106,7 +109,8 @@ static void netlbl_domhsh_free_entry(struct rcu_head *entry) * Description: * This is the hashing function for the domain hash table, it returns the * correct bucket number for the domain. The caller is responsibile for - * calling the rcu_read_[un]lock() functions. + * ensuring that the hash table is protected with either a RCU read lock or the + * hash table lock. * */ static u32 netlbl_domhsh_hash(const char *key) @@ -120,7 +124,7 @@ static u32 netlbl_domhsh_hash(const char *key) for (iter = 0, val = 0, len = strlen(key); iter < len; iter++) val = (val << 4 | (val >> (8 * sizeof(u32) - 4))) ^ key[iter]; - return val & (rcu_dereference(netlbl_domhsh)->size - 1); + return val & (netlbl_domhsh_rcu_deref(netlbl_domhsh)->size - 1); } /** @@ -130,7 +134,8 @@ static u32 netlbl_domhsh_hash(const char *key) * Description: * Searches the domain hash table and returns a pointer to the hash table * entry if found, otherwise NULL is returned. The caller is responsibile for - * the rcu hash table locks (i.e. the caller much call rcu_read_[un]lock()). + * ensuring that the hash table is protected with either a RCU read lock or the + * hash table lock. * */ static struct netlbl_dom_map *netlbl_domhsh_search(const char *domain) @@ -141,7 +146,7 @@ static struct netlbl_dom_map *netlbl_domhsh_search(const char *domain) if (domain != NULL) { bkt = netlbl_domhsh_hash(domain); - bkt_list = &rcu_dereference(netlbl_domhsh)->tbl[bkt]; + bkt_list = &netlbl_domhsh_rcu_deref(netlbl_domhsh)->tbl[bkt]; list_for_each_entry_rcu(iter, bkt_list, list) if (iter->valid && strcmp(iter->domain, domain) == 0) return iter; @@ -159,8 +164,8 @@ static struct netlbl_dom_map *netlbl_domhsh_search(const char *domain) * Searches the domain hash table and returns a pointer to the hash table * entry if an exact match is found, if an exact match is not present in the * hash table then the default entry is returned if valid otherwise NULL is - * returned. The caller is responsibile for the rcu hash table locks - * (i.e. the caller much call rcu_read_[un]lock()). + * returned. The caller is responsibile ensuring that the hash table is + * protected with either a RCU read lock or the hash table lock. * */ static struct netlbl_dom_map *netlbl_domhsh_search_def(const char *domain) @@ -169,7 +174,7 @@ static struct netlbl_dom_map *netlbl_domhsh_search_def(const char *domain) entry = netlbl_domhsh_search(domain); if (entry == NULL) { - entry = rcu_dereference(netlbl_domhsh_def); + entry = netlbl_domhsh_rcu_deref(netlbl_domhsh_def); if (entry != NULL && !entry->valid) entry = NULL; } @@ -306,8 +311,11 @@ int netlbl_domhsh_add(struct netlbl_dom_map *entry, struct netlbl_af6list *tmp6; #endif /* IPv6 */ + /* XXX - we can remove this RCU read lock as the spinlock protects the + * entire function, but before we do we need to fixup the + * netlbl_af[4,6]list RCU functions to do "the right thing" with + * respect to rcu_dereference() when only a spinlock is held. */ rcu_read_lock(); - spin_lock(&netlbl_domhsh_lock); if (entry->domain != NULL) entry_old = netlbl_domhsh_search(entry->domain); diff --git a/net/netlabel/netlabel_unlabeled.c b/net/netlabel/netlabel_unlabeled.c index 852d9d7976b9..3b4fde7622a3 100644 --- a/net/netlabel/netlabel_unlabeled.c +++ b/net/netlabel/netlabel_unlabeled.c @@ -114,6 +114,9 @@ struct netlbl_unlhsh_walk_arg { /* updates should be so rare that having one spinlock for the entire * hash table should be okay */ static DEFINE_SPINLOCK(netlbl_unlhsh_lock); +#define netlbl_unlhsh_rcu_deref(p) \ + rcu_dereference_check(p, rcu_read_lock_held() || \ + lockdep_is_held(&netlbl_unlhsh_lock)) static struct netlbl_unlhsh_tbl *netlbl_unlhsh = NULL; static struct netlbl_unlhsh_iface *netlbl_unlhsh_def = NULL; @@ -235,15 +238,13 @@ static void netlbl_unlhsh_free_iface(struct rcu_head *entry) * Description: * This is the hashing function for the unlabeled hash table, it returns the * bucket number for the given device/interface. The caller is responsible for - * calling the rcu_read_[un]lock() functions. + * ensuring that the hash table is protected with either a RCU read lock or + * the hash table lock. * */ static u32 netlbl_unlhsh_hash(int ifindex) { - /* this is taken _almost_ directly from - * security/selinux/netif.c:sel_netif_hasfn() as they do pretty much - * the same thing */ - return ifindex & (rcu_dereference(netlbl_unlhsh)->size - 1); + return ifindex & (netlbl_unlhsh_rcu_deref(netlbl_unlhsh)->size - 1); } /** @@ -253,7 +254,8 @@ static u32 netlbl_unlhsh_hash(int ifindex) * Description: * Searches the unlabeled connection hash table and returns a pointer to the * interface entry which matches @ifindex, otherwise NULL is returned. The - * caller is responsible for calling the rcu_read_[un]lock() functions. + * caller is responsible for ensuring that the hash table is protected with + * either a RCU read lock or the hash table lock. * */ static struct netlbl_unlhsh_iface *netlbl_unlhsh_search_iface(int ifindex) @@ -263,7 +265,7 @@ static struct netlbl_unlhsh_iface *netlbl_unlhsh_search_iface(int ifindex) struct netlbl_unlhsh_iface *iter; bkt = netlbl_unlhsh_hash(ifindex); - bkt_list = &rcu_dereference(netlbl_unlhsh)->tbl[bkt]; + bkt_list = &netlbl_unlhsh_rcu_deref(netlbl_unlhsh)->tbl[bkt]; list_for_each_entry_rcu(iter, bkt_list, list) if (iter->valid && iter->ifindex == ifindex) return iter; @@ -272,33 +274,6 @@ static struct netlbl_unlhsh_iface *netlbl_unlhsh_search_iface(int ifindex) } /** - * netlbl_unlhsh_search_iface_def - Search for a matching interface entry - * @ifindex: the network interface - * - * Description: - * Searches the unlabeled connection hash table and returns a pointer to the - * interface entry which matches @ifindex. If an exact match can not be found - * and there is a valid default entry, the default entry is returned, otherwise - * NULL is returned. The caller is responsible for calling the - * rcu_read_[un]lock() functions. - * - */ -static struct netlbl_unlhsh_iface *netlbl_unlhsh_search_iface_def(int ifindex) -{ - struct netlbl_unlhsh_iface *entry; - - entry = netlbl_unlhsh_search_iface(ifindex); - if (entry != NULL) - return entry; - - entry = rcu_dereference(netlbl_unlhsh_def); - if (entry != NULL && entry->valid) - return entry; - - return NULL; -} - -/** * netlbl_unlhsh_add_addr4 - Add a new IPv4 address entry to the hash table * @iface: the associated interface entry * @addr: IPv4 address in network byte order @@ -308,8 +283,7 @@ static struct netlbl_unlhsh_iface *netlbl_unlhsh_search_iface_def(int ifindex) * Description: * Add a new address entry into the unlabeled connection hash table using the * interface entry specified by @iface. On success zero is returned, otherwise - * a negative value is returned. The caller is responsible for calling the - * rcu_read_[un]lock() functions. + * a negative value is returned. * */ static int netlbl_unlhsh_add_addr4(struct netlbl_unlhsh_iface *iface, @@ -349,8 +323,7 @@ static int netlbl_unlhsh_add_addr4(struct netlbl_unlhsh_iface *iface, * Description: * Add a new address entry into the unlabeled connection hash table using the * interface entry specified by @iface. On success zero is returned, otherwise - * a negative value is returned. The caller is responsible for calling the - * rcu_read_[un]lock() functions. + * a negative value is returned. * */ static int netlbl_unlhsh_add_addr6(struct netlbl_unlhsh_iface *iface, @@ -391,8 +364,7 @@ static int netlbl_unlhsh_add_addr6(struct netlbl_unlhsh_iface *iface, * Description: * Add a new, empty, interface entry into the unlabeled connection hash table. * On success a pointer to the new interface entry is returned, on failure NULL - * is returned. The caller is responsible for calling the rcu_read_[un]lock() - * functions. + * is returned. * */ static struct netlbl_unlhsh_iface *netlbl_unlhsh_add_iface(int ifindex) @@ -415,10 +387,10 @@ static struct netlbl_unlhsh_iface *netlbl_unlhsh_add_iface(int ifindex) if (netlbl_unlhsh_search_iface(ifindex) != NULL) goto add_iface_failure; list_add_tail_rcu(&iface->list, - &rcu_dereference(netlbl_unlhsh)->tbl[bkt]); + &netlbl_unlhsh_rcu_deref(netlbl_unlhsh)->tbl[bkt]); } else { INIT_LIST_HEAD(&iface->list); - if (rcu_dereference(netlbl_unlhsh_def) != NULL) + if (netlbl_unlhsh_rcu_deref(netlbl_unlhsh_def) != NULL) goto add_iface_failure; rcu_assign_pointer(netlbl_unlhsh_def, iface); } @@ -548,8 +520,7 @@ unlhsh_add_return: * * Description: * Remove an IP address entry from the unlabeled connection hash table. - * Returns zero on success, negative values on failure. The caller is - * responsible for calling the rcu_read_[un]lock() functions. + * Returns zero on success, negative values on failure. * */ static int netlbl_unlhsh_remove_addr4(struct net *net, @@ -611,8 +582,7 @@ static int netlbl_unlhsh_remove_addr4(struct net *net, * * Description: * Remove an IP address entry from the unlabeled connection hash table. - * Returns zero on success, negative values on failure. The caller is - * responsible for calling the rcu_read_[un]lock() functions. + * Returns zero on success, negative values on failure. * */ static int netlbl_unlhsh_remove_addr6(struct net *net, @@ -1547,8 +1517,10 @@ int netlbl_unlabel_getattr(const struct sk_buff *skb, struct netlbl_unlhsh_iface *iface; rcu_read_lock(); - iface = netlbl_unlhsh_search_iface_def(skb->skb_iif); + iface = netlbl_unlhsh_search_iface(skb->skb_iif); if (iface == NULL) + iface = rcu_dereference(netlbl_unlhsh_def); + if (iface == NULL || !iface->valid) goto unlabel_getattr_nolabel; switch (family) { case PF_INET: { |