[PATCH 5.18 0764/1095] RDMA/irdma: Fix a window for use-after-free

[Greg Kroah-Hartman]

From: Mustafa Ismail <mustafa.ismail@xxxxxxxxx>

[ Upstream commit 8ecef7890b3aea78c8bbb501a4b5b8134367b821 ]

During a destroy CQ an interrupt may cause processing of a CQE after CQ
resources are freed by irdma_cq_free_rsrc(). Fix this by moving the call
to irdma_cq_free_rsrc() after the irdma_sc_cleanup_ceqes(), which is
called under the cq_lock.

Fixes: b48c24c2d710 ("RDMA/irdma: Implement device supported verb APIs")
Link: https://lore.kernel.org/r/20220705230815.265-6-shiraz.saleem@xxxxxxxxx
Signed-off-by: Bartosz Sobczak <bartosz.sobczak@xxxxxxxxx>
Signed-off-by: Mustafa Ismail <mustafa.ismail@xxxxxxxxx>
Signed-off-by: Shiraz Saleem <shiraz.saleem@xxxxxxxxx>
Signed-off-by: Leon Romanovsky <leon@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
 drivers/infiniband/hw/irdma/verbs.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/infiniband/hw/irdma/verbs.c b/drivers/infiniband/hw/irdma/verbs.c
index 6daa149dcbda..b29631f6659a 100644
--- a/drivers/infiniband/hw/irdma/verbs.c
+++ b/drivers/infiniband/hw/irdma/verbs.c
@@ -1760,11 +1760,11 @@ static int irdma_destroy_cq(struct ib_cq *ib_cq, struct ib_udata *udata)
 	spin_unlock_irqrestore(&iwcq->lock, flags);
 
 	irdma_cq_wq_destroy(iwdev->rf, cq);
-	irdma_cq_free_rsrc(iwdev->rf, iwcq);
 
 	spin_lock_irqsave(&iwceq->ce_lock, flags);
 	irdma_sc_cleanup_ceqes(cq, ceq);
 	spin_unlock_irqrestore(&iwceq->ce_lock, flags);
+	irdma_cq_free_rsrc(iwdev->rf, iwcq);
 
 	return 0;
 }
-- 
2.35.1