[PATCH 06/11] RDMA/nes: abnormal listener termination causes loopback node crash

Faisal Latif
2009-12-09T22:41:15Z

when listener is destroyed for loopback connection, listener node is
getting reset event. This causes crash as listener is not expecting
reset event. Code review of cm_event_reset() durring debugging showed
the cm_id ref count in incrementing after calling its event handler
and not before.

Signed-off-by: Faisal Latif <faisal.latif-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>
---
drivers/infiniband/hw/nes/nes_cm.c | 16 +++-------------
1 files changed, 3 insertions(+), 13 deletions(-)

diff --git a/drivers/infiniband/hw/nes/nes_cm.c b/drivers/infiniband/hw/nes/nes_cm.c
index ec04786..20e21f1 100644
--- a/drivers/infiniband/hw/nes/nes_cm.c
+++ b/drivers/infiniband/hw/nes/nes_cm.c
@@ -1014,18 +1014,6 @@ static int mini_cm_dec_refcnt_listen(struct nes_cm_core *cm_core,
cm_node->state = NES_CM_STATE_LISTENER_DESTROYED;
loopback->state = NES_CM_STATE_CLOSED;

- event.cm_node = cm_node;
- event.cm_info.rem_addr =
- cm_node->rem_addr;
- event.cm_info.loc_addr =
- cm_node->loc_addr;
- event.cm_info.rem_port =
- cm_node->rem_port;
- event.cm_info.loc_port =
- cm_node->loc_port;
- event.cm_info.cm_id = cm_node->cm_id;
- cm_event_reset(&event);
-
rem_ref_cm_node(cm_node->cm_core,
cm_node);

@@ -3440,6 +3428,8 @@ static void cm_event_reset(struct nes_cm_event *event)

nes_debug(NES_DBG_CM, "%p - cm_id = %p\n", event->cm_node, cm_id);
nesqp = cm_id->provider_data;
+ if (!nesqp)
+ return;

nesqp->cm_id = NULL;
/* cm_id->provider_data = NULL; */
@@ -3451,8 +3441,8 @@ static void cm_event_reset(struct nes_cm_event *event)
cm_event.private_data = NULL;
cm_event.private_data_len = 0;

- ret = cm_id->event_handler(cm_id, &cm_event);
cm_id->add_ref(cm_id);
+ ret = cm_id->event_handler(cm_id, &cm_event);
atomic_inc(&cm_closes);
cm_event.event = IW_CM_EVENT_CLOSE;
cm_event.status = IW_CM_EVENT_STATUS_OK;
--
1.5.3.3