[PATCH AUTOSEL 5.0 003/173] rapidio: fix a NULL pointer dereference when create_workqueue() fails

Sasha Levin
2019-06-01T13:41:01Z

From: Kangjie Lu <kjlu@umn.edu>

[ Upstream commit 23015b22e47c5409620b1726a677d69e5cd032ba ]

In case create_workqueue fails, the fix releases resources and returns
-ENOMEM to avoid NULL pointer dereference.

Signed-off-by: Kangjie Lu <kjlu@umn.edu>
Acked-by: Alexandre Bounine <alex.bou9@gmail.com>
Cc: Matt Porter <mporter@kernel.crashing.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/rapidio/rio_cm.c | 8 ++++++++
1 file changed, 8 insertions(+)

diff --git a/drivers/rapidio/rio_cm.c b/drivers/rapidio/rio_cm.c
index bad0e0ea4f305..ef989a15aefc4 100644
--- a/drivers/rapidio/rio_cm.c
+++ b/drivers/rapidio/rio_cm.c
@@ -2145,6 +2145,14 @@ static int riocm_add_mport(struct device *dev,
mutex_init(&cm->rx_lock);
riocm_rx_fill(cm, RIOCM_RX_RING_SIZE);
cm->rx_wq = create_workqueue(DRV_NAME "/rxq");
+ if (!cm->rx_wq) {
+ riocm_error("failed to allocate IBMBOX_%d on %s",
+ cmbox, mport->name);
+ rio_release_outb_mbox(mport, cmbox);
+ kfree(cm);
+ return -ENOMEM;
+ }
+
INIT_WORK(&cm->rx_work, rio_ibmsg_handler);

cm->tx_slot = 0;
--
2.20.1