libertas: check return value of alloc_workqueue

Function alloc_workqueue() will return a NULL pointer if there is no
enough memory, and its return value should be validated before using.
However, in function if_spi_probe(), its return value is not checked.
This may result in a NULL dereference bug. This patch fixes the bug.

Signed-off-by: Pan Bian <bianpan2016@163.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>

diff --git a/drivers/net/wireless/marvell/libertas/if_spi.c b/drivers/net/wireless/marvell/libertas/if_spi.c
index c3a53cd..7b4955c 100644 (file)
--- a/drivers/net/wireless/marvell/libertas/if_spi.c
+++ b/drivers/net/wireless/marvell/libertas/if_spi.c
@@ -1181,6 +1181,10 @@ static int if_spi_probe(struct spi_device *spi)
 
        /* Initialize interrupt handling stuff. */
        card->workqueue = alloc_workqueue("libertas_spi", WQ_MEM_RECLAIM, 0);
+       if (!card->workqueue) {
+               err = -ENOMEM;
+               goto remove_card;
+       }
        INIT_WORK(&card->packet_work, if_spi_host_to_card_worker);
        INIT_WORK(&card->resume_work, if_spi_resume_worker);
 
@@ -1209,6 +1213,7 @@ release_irq:
        free_irq(spi->irq, card);
 terminate_workqueue:
        destroy_workqueue(card->workqueue);
+remove_card:
        lbs_remove_card(priv); /* will call free_netdev */
 free_card:
        free_if_spi_card(card);