summary refs log tree commit diff
path: root/net/netlabel
diff options
context:
space:
mode:
authorLinus Torvalds <torvalds@linux-foundation.org>2010-04-06 08:34:06 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2010-04-06 08:34:06 -0700
commitcb4361c1dc29cd870f664c004b1817106fbce0fa (patch)
treec31533210d738c9074b21b8f31fe0399b39545f0 /net/netlabel
parent309361e09ca9e9670dc8664e5d14125bf82078af (diff)
parentfb9e2d887243499b8d28efcf80821c4f6a092395 (diff)
downloadlinux-cb4361c1dc29cd870f664c004b1817106fbce0fa.tar.gz
Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6: (37 commits)
  smc91c92_cs: fix the problem of "Unable to find hardware address"
  r8169: clean up my printk uglyness
  net: Hook up cxgb4 to Kconfig and Makefile
  cxgb4: Add main driver file and driver Makefile
  cxgb4: Add remaining driver headers and L2T management
  cxgb4: Add packet queues and packet DMA code
  cxgb4: Add HW and FW support code
  cxgb4: Add register, message, and FW definitions
  netlabel: Fix several rcu_dereference() calls used without RCU read locks
  bonding: fix potential deadlock in bond_uninit()
  net: check the length of the socket address passed to connect(2)
  stmmac: add documentation for the driver.
  stmmac: fix kconfig for crc32 build error
  be2net: fix bug in vlan rx path for big endian architecture
  be2net: fix flashing on big endian architectures
  be2net: fix a bug in flashing the redboot section
  bonding: bond_xmit_roundrobin() fix
  drivers/net: Add missing unlock
  net: gianfar - align BD ring size console messages
  net: gianfar - initialize per-queue statistics
  ...
Diffstat (limited to 'net/netlabel')
-rw-r--r--net/netlabel/netlabel_domainhash.c28
-rw-r--r--net/netlabel/netlabel_unlabeled.c66
2 files changed, 37 insertions, 57 deletions
diff --git a/net/netlabel/netlabel_domainhash.c b/net/netlabel/netlabel_domainhash.c
index 016ab9c75ebd..d37b7f80fa37 100644
--- a/net/netlabel/netlabel_domainhash.c
+++ b/net/netlabel/netlabel_domainhash.c
@@ -51,9 +51,12 @@ 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;
 
@@ -107,7 +110,8 @@ 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)
@@ -121,7 +125,7 @@ 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);
 }
 
 /**
@@ -131,7 +135,8 @@ 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)
@@ -142,7 +147,7 @@ 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;
@@ -160,8 +165,8 @@ 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)
@@ -170,7 +175,7 @@ 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;
 	}
@@ -307,8 +312,11 @@ 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 d7ea2cf390b7..a3d64aabe2f7 100644
--- a/net/netlabel/netlabel_unlabeled.c
+++ b/net/netlabel/netlabel_unlabeled.c
@@ -115,6 +115,9 @@ 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;
 
@@ -236,15 +239,13 @@ 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);
 }
 
 /**
@@ -254,7 +255,8 @@ 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)
@@ -264,7 +266,7 @@ 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;
@@ -273,33 +275,6 @@ 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
@@ -309,8 +284,7 @@ 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,
@@ -350,8 +324,7 @@ 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,
@@ -392,8 +365,7 @@ 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)
@@ -416,10 +388,10 @@ 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);
 	}
@@ -549,8 +521,7 @@ 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,
@@ -612,8 +583,7 @@ 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,
@@ -1548,8 +1518,10 @@ 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: {