tree 64c23596491de6e9e11fb197e1b8188c02e0437a
parent fbac2c5be9fd7893eba6c36e86eec1f49e95e9c6
author Shang XiaoJing <shangxiaojing@huawei.com> 1668653114 +0800
committer Greg Kroah-Hartman <gregkh@linuxfoundation.org> 1673089657 +0100

parisc: led: Fix potential null-ptr-deref in start_task()

commit 41f563ab3c33698bdfc3403c7c2e6c94e73681e4 upstream.

start_task() calls create_singlethread_workqueue() and not checked the
ret value, which may return NULL. And a null-ptr-deref may happen:

start_task()
    create_singlethread_workqueue() # failed, led_wq is NULL
    queue_delayed_work()
        queue_delayed_work_on()
            __queue_delayed_work()  # warning here, but continue
                __queue_work()      # access wq->flags, null-ptr-deref

Check the ret value and return -ENOMEM if it is NULL.

Fixes: 3499495205a6 ("[PARISC] Use work queue in LED/LCD driver instead of tasklet.")
Signed-off-by: Shang XiaoJing <shangxiaojing@huawei.com>
Signed-off-by: Helge Deller <deller@gmx.de>
Cc: <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>