[PATCH AUTOSEL 4.4 27/31] RDMA/cma: Fix rdma_resolve_route() memory leak

[Sasha Levin]

From: Gerd Rausch <gerd.rausch@xxxxxxxxxx>

[ Upstream commit 74f160ead74bfe5f2b38afb4fcf86189f9ff40c9 ]

Fix a memory leak when "mda_resolve_route() is called more than once on
the same "rdma_cm_id".

This is possible if cma_query_handler() triggers the
RDMA_CM_EVENT_ROUTE_ERROR flow which puts the state machine back and
allows rdma_resolve_route() to be called again.

Link: https://lore.kernel.org/r/f6662b7b-bdb7-2706-1e12-47c61d3474b6@xxxxxxxxxx
Signed-off-by: Gerd Rausch <gerd.rausch@xxxxxxxxxx>
Signed-off-by: Jason Gunthorpe <jgg@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
 drivers/infiniband/core/cma.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/infiniband/core/cma.c b/drivers/infiniband/core/cma.c
index b59a4a819aaa..b5e7bd23857e 100644
--- a/drivers/infiniband/core/cma.c
+++ b/drivers/infiniband/core/cma.c
@@ -2227,7 +2227,8 @@ static int cma_resolve_ib_route(struct rdma_id_private *id_priv, int timeout_ms)
 	work->new_state = RDMA_CM_ROUTE_RESOLVED;
 	work->event.event = RDMA_CM_EVENT_ROUTE_RESOLVED;
 
-	route->path_rec = kmalloc(sizeof *route->path_rec, GFP_KERNEL);
+	if (!route->path_rec)
+		route->path_rec = kmalloc(sizeof *route->path_rec, GFP_KERNEL);
 	if (!route->path_rec) {
 		ret = -ENOMEM;
 		goto err1;
-- 
2.30.2