[SCTP]: Add bind hash locking to the migrate code
SCTP accept code tries to add a newliy created socket
to a bind bucket without holding a lock. On a really
busy system, that can causes slab corruptions.
Add a lock around this code.
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/sctp/socket.c b/net/sctp/socket.c
index ff8bc95..9f5d793 100644
--- a/net/sctp/socket.c
+++ b/net/sctp/socket.c
@@ -6325,6 +6325,7 @@
struct sctp_endpoint *newep = newsp->ep;
struct sk_buff *skb, *tmp;
struct sctp_ulpevent *event;
+ struct sctp_bind_hashbucket *head;
int flags = 0;
/* Migrate socket buffer sizes and all the socket level options to the
@@ -6342,10 +6343,15 @@
newsp->hmac = NULL;
/* Hook this new socket in to the bind_hash list. */
+ head = &sctp_port_hashtable[sctp_phashfn(inet_sk(oldsk)->num)];
+ sctp_local_bh_disable();
+ sctp_spin_lock(&head->lock);
pp = sctp_sk(oldsk)->bind_hash;
sk_add_bind_node(newsk, &pp->owner);
sctp_sk(newsk)->bind_hash = pp;
inet_sk(newsk)->num = inet_sk(oldsk)->num;
+ sctp_spin_unlock(&head->lock);
+ sctp_local_bh_enable();
/* Copy the bind_addr list from the original endpoint to the new
* endpoint so that we can handle restarts properly
