[ 24/36] sctp: refactor sctp_outq_teardown to insure proper re-initalization

Greg Kroah-Hartman
2013-02-12T20:43:24Z

From: Neil Horman <nhorman@tuxdriver.com>

[ Upstream commit 2f94aabd9f6c925d77aecb3ff020f1cc12ed8f86 ]

Jamie Parsons reported a problem recently, in which the re-initalization of an
association (The duplicate init case), resulted in a loss of receive window
space. He tracked down the root cause to sctp_outq_teardown, which discarded
all the data on an outq during a re-initalization of the corresponding
association, but never reset the outq->outstanding_data field to zero. I wrote,
and he tested this fix, which does a proper full re-initalization of the outq,
fixing this problem, and hopefully future proofing us from simmilar issues down
the road.

Signed-off-by: Neil Horman <nhorman@tuxdriver.com>
Reported-by: Jamie Parsons <Jamie.Parsons@metaswitch.com>
Tested-by: Jamie Parsons <Jamie.Parsons@metaswitch.com>
CC: Jamie Parsons <Jamie.Parsons@metaswitch.com>
CC: Vlad Yasevich <vyasevich@gmail.com>
CC: "David S. Miller" <davem@davemloft.net>
CC: netdev@vger.kernel.org
Acked-by: Vlad Yasevich <vyasevich@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
net/sctp/outqueue.c | 12 ++++++++----
1 file changed, 8 insertions(+), 4 deletions(-)

--- a/net/sctp/outqueue.c
+++ b/net/sctp/outqueue.c
@@ -223,7 +223,7 @@ void sctp_outq_init(struct sctp_associat

/* Free the outqueue structure and any related pending chunks.
*/
-void sctp_outq_teardown(struct sctp_outq *q)
+static void __sctp_outq_teardown(struct sctp_outq *q)
{
struct sctp_transport *transport;
struct list_head *lchunk, *temp;
@@ -276,8 +276,6 @@ void sctp_outq_teardown(struct sctp_outq
sctp_chunk_free(chunk);
}

- q->error = 0;
-
/* Throw away any leftover control chunks. */
list_for_each_entry_safe(chunk, tmp, &q->control_chunk_list, list) {
list_del_init(&chunk->list);
@@ -285,11 +283,17 @@ void sctp_outq_teardown(struct sctp_outq
}
}

+void sctp_outq_teardown(struct sctp_outq *q)
+{
+ __sctp_outq_teardown(q);
+ sctp_outq_init(q->asoc, q);
+}
+
/* Free the outqueue structure and any related pending chunks. */
void sctp_outq_free(struct sctp_outq *q)
{
/* Throw away leftover chunks. */
- sctp_outq_teardown(q);
+ __sctp_outq_teardown(q);

/* If we were kmalloc()'d, free the memory. */
if (q->malloced)