From f2e4a30c4158031dcbf6cc627cd8fd73b3f75e0e Mon Sep 17 00:00:00 2001 From: Tariq Saeed Date: Thu, 22 May 2014 10:42:32 +1000 Subject: [PATCH] ocfs2/o2net: incorrect to terminate accepting connections loop upon rejecting an invalid one Orabug: 17489469 When o2net-accept-one() rejects an illegal connection, it terminates the loop picking up the remaining queued connections. This fix will continue accepting connections till the queue is emtpy. Signed-off-by: Tariq Saseed Signed-off-by: Srinivas Eeda Cc: Joel Becker Reviewed-by: Mark Fasheh Signed-off-by: Andrew Morton --- fs/ocfs2/cluster/tcp.c | 18 ++++++++++++++++++ 1 file changed, 18 insertions(+) diff --git a/fs/ocfs2/cluster/tcp.c b/fs/ocfs2/cluster/tcp.c index 40cc827afcde..681691bc233a 100644 --- a/fs/ocfs2/cluster/tcp.c +++ b/fs/ocfs2/cluster/tcp.c @@ -1921,12 +1921,30 @@ out: return ret; } +/* + * This function is invoked in response to one or more + * pending accepts at softIRQ level. We must drain the + * entire que before returning. + */ + static void o2net_accept_many(struct work_struct *work) { struct socket *sock = o2net_listen_sock; int more; int err; + /* + * It is critical to note that due to interrupt moderation + * at the network driver level, we can't assume to get a + * softIRQ for every single conn since tcp SYN packets + * can arrive back-to-back, and therefore many pending + * accepts may result in just 1 softIRQ. If we terminate + * the o2net_accept_one() loop upon seeing an err, what happens + * to the rest of the conns in the queue? If no new SYN + * arrives for hours, no softIRQ will be delivered, + * and the connections will just sit in the queue. + */ + for (;;) { err = o2net_accept_one(sock, &more); if (!more) -- 2.39.5