sctp: fix copying more bytes than expected in sctp_add_bind_addr

[cascardo/linux.git] / net / sctp / protocol.c

diff --git a/net/sctp/protocol.c b/net/sctp/protocol.c
index ab0d538..d3d50da 100644 (file)
--- a/net/sctp/protocol.c
+++ b/net/sctp/protocol.c
@@ -60,6 +60,8 @@
 #include <net/inet_common.h>
 #include <net/inet_ecn.h>
 
+#define MAX_SCTP_PORT_HASH_ENTRIES (64 * 1024)
+
 /* Global data structures. */
 struct sctp_globals sctp_globals __read_mostly;
 
@@ -214,6 +216,7 @@ int sctp_copy_local_addr_list(struct net *net, struct sctp_bind_addr *bp,
                              (copy_flags & SCTP_ADDR6_ALLOWED) &&
                              (copy_flags & SCTP_ADDR6_PEERSUPP)))) {
                                error = sctp_add_bind_addr(bp, &addr->a,
+                                                   sizeof(addr->a),
                                                    SCTP_ADDR_SRC, GFP_ATOMIC);
                                if (error)
                                        goto end_copy;
@@ -1355,6 +1358,8 @@ static __init int sctp_init(void)
        unsigned long limit;
        int max_share;
        int order;
+       int num_entries;
+       int max_entry_order;
 
        sock_skb_cb_check_size(sizeof(struct sctp_ulpevent));
 
@@ -1407,14 +1412,24 @@ static __init int sctp_init(void)
 
        /* Size and allocate the association hash table.
         * The methodology is similar to that of the tcp hash tables.
+        * Though not identical.  Start by getting a goal size
         */
        if (totalram_pages >= (128 * 1024))
                goal = totalram_pages >> (22 - PAGE_SHIFT);
        else
                goal = totalram_pages >> (24 - PAGE_SHIFT);
 
-       for (order = 0; (1UL << order) < goal; order++)
-               ;
+       /* Then compute the page order for said goal */
+       order = get_order(goal);
+
+       /* Now compute the required page order for the maximum sized table we
+        * want to create
+        */
+       max_entry_order = get_order(MAX_SCTP_PORT_HASH_ENTRIES *
+                                   sizeof(struct sctp_bind_hashbucket));
+
+       /* Limit the page order by that maximum hash table size */
+       order = min(order, max_entry_order);
 
        /* Allocate and initialize the endpoint hash table.  */
        sctp_ep_hashsize = 64;
@@ -1430,20 +1445,35 @@ static __init int sctp_init(void)
                INIT_HLIST_HEAD(&sctp_ep_hashtable[i].chain);
        }
 
-       /* Allocate and initialize the SCTP port hash table.  */
+       /* Allocate and initialize the SCTP port hash table.
+        * Note that order is initalized to start at the max sized
+        * table we want to support.  If we can't get that many pages
+        * reduce the order and try again
+        */
        do {
-               sctp_port_hashsize = (1UL << order) * PAGE_SIZE /
-                                       sizeof(struct sctp_bind_hashbucket);
-               if ((sctp_port_hashsize > (64 * 1024)) && order > 0)
-                       continue;
                sctp_port_hashtable = (struct sctp_bind_hashbucket *)
                        __get_free_pages(GFP_KERNEL | __GFP_NOWARN, order);
        } while (!sctp_port_hashtable && --order > 0);
+
        if (!sctp_port_hashtable) {
                pr_err("Failed bind hash alloc\n");
                status = -ENOMEM;
                goto err_bhash_alloc;
        }
+
+       /* Now compute the number of entries that will fit in the
+        * port hash space we allocated
+        */
+       num_entries = (1UL << order) * PAGE_SIZE /
+                     sizeof(struct sctp_bind_hashbucket);
+
+       /* And finish by rounding it down to the nearest power of two
+        * this wastes some memory of course, but its needed because
+        * the hash function operates based on the assumption that
+        * that the number of entries is a power of two
+        */
+       sctp_port_hashsize = rounddown_pow_of_two(num_entries);
+
        for (i = 0; i < sctp_port_hashsize; i++) {
                spin_lock_init(&sctp_port_hashtable[i].lock);
                INIT_HLIST_HEAD(&sctp_port_hashtable[i].chain);
@@ -1452,7 +1482,8 @@ static __init int sctp_init(void)
        if (sctp_transport_hashtable_init())
                goto err_thash_alloc;
 
-       pr_info("Hash tables configured (bind %d)\n", sctp_port_hashsize);
+       pr_info("Hash tables configured (bind %d/%d)\n", sctp_port_hashsize,
+               num_entries);
 
        sctp_sysctl_register();