rapidio: fix a NULL pointer dereference when create_workqueue() fails

[ 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>

diff --git a/drivers/rapidio/rio_cm.c b/drivers/rapidio/rio_cm.c
index bad0e0e..ef989a1 100644 (file)
--- 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;