releases/3.16.3/libceph-gracefully-handle-large-reply-messages-from-the-mon.patch

   1 From 73c3d4812b4c755efeca0140f606f83772a39ce4 Mon Sep 17 00:00:00 2001
   2 From: Sage Weil <sage@redhat.com>
   3 Date: Mon, 4 Aug 2014 07:01:54 -0700
   4 Subject: libceph: gracefully handle large reply messages from the mon
   5
   6 From: Sage Weil <sage@redhat.com>
   7
   8 commit 73c3d4812b4c755efeca0140f606f83772a39ce4 upstream.
   9
  10 We preallocate a few of the message types we get back from the mon.  If we
  11 get a larger message than we are expecting, fall back to trying to allocate
  12 a new one instead of blindly using the one we have.
  13
  14 Signed-off-by: Sage Weil <sage@redhat.com>
  15 Reviewed-by: Ilya Dryomov <ilya.dryomov@inktank.com>
  16 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
  17
  18 ---
  19  net/ceph/mon_client.c |    8 ++++++++
  20  1 file changed, 8 insertions(+)
  21
  22 --- a/net/ceph/mon_client.c
  23 +++ b/net/ceph/mon_client.c
  24 @@ -1181,7 +1181,15 @@ static struct ceph_msg *mon_alloc_msg(st
  25         if (!m) {
  26                 pr_info("alloc_msg unknown type %d\n", type);
  27                 *skip = 1;
  28 +       } else if (front_len > m->front_alloc_len) {
  29 +               pr_warning("mon_alloc_msg front %d > prealloc %d (%u#%llu)\n",
  30 +                          front_len, m->front_alloc_len,
  31 +                          (unsigned int)con->peer_name.type,
  32 +                          le64_to_cpu(con->peer_name.num));
  33 +               ceph_msg_put(m);
  34 +               m = ceph_msg_new(type, front_len, GFP_NOFS, false);
  35         }
  36 +
  37         return m;
  38  }
  39