From: Bharat Potnuri <bharat@chelsio.com>
Date: Tue, 1 Aug 2017 10:58:35 +0530
Subject: [PATCH] RDMA/uverbs: Initialize cq_context appropriately
References: bnc#1060662
Patch-mainline: v4.12.10
Git-commit: 65159c051c45f269cf40a14f9404248f2d524920
Git-commit: 699a2d5b1b880b4e4e1c7d55fa25659322cf5b51

commit 65159c051c45f269cf40a14f9404248f2d524920 upstream.

Initializing cq_context with ev_queue in create_cq(), leads to NULL pointer
dereference in ib_uverbs_comp_handler(), if application doesnot use completion
channel. This patch fixes the cq_context initialization.

Fixes: 1e7710f3f65 ("IB/core: Change completion channel to use the reworked")
Signed-off-by: Potnuri Bharat Teja <bharat@chelsio.com>
Reviewed-by: Matan Barak <matanb@mellanox.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
(cherry picked from commit 699a2d5b1b880b4e4e1c7d55fa25659322cf5b51)
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
---
 drivers/infiniband/core/uverbs_cmd.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/infiniband/core/uverbs_cmd.c b/drivers/infiniband/core/uverbs_cmd.c
index f3f9d0b5dce0..5ea2d80800f9 100644
--- a/drivers/infiniband/core/uverbs_cmd.c
+++ b/drivers/infiniband/core/uverbs_cmd.c
@@ -1015,7 +1015,7 @@ static struct ib_ucq_object *create_cq(struct ib_uverbs_file *file,
 	cq->uobject       = &obj->uobject;
 	cq->comp_handler  = ib_uverbs_comp_handler;
 	cq->event_handler = ib_uverbs_cq_event_handler;
-	cq->cq_context    = &ev_file->ev_queue;
+	cq->cq_context    = ev_file ? &ev_file->ev_queue : NULL;
 	atomic_set(&cq->usecnt, 0);
 
 	obj->uobject.object = cq;
-- 
2.14.2