diff options
| author | Ian Abbott <abbotti@mev.co.uk> | 2013-08-20 11:50:19 +0100 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2013-12-20 07:45:11 -0800 |
| commit | bc049656c27b34c9b1f5f36ffa95f7a73b82c8a4 (patch) | |
| tree | 4d23d72881eba231d629b2bce6dd5bf5bf373c42 | |
| parent | 5232a7194556c819b2cea0b8395895dc5a448aae (diff) | |
staging: comedi: pcmuio: fix possible NULL deref on detach
commit 2fd2bdfccae61efe18f6b92b6a45fbf936d75b48 upstream.
pcmuio_detach() is called by the comedi core even if pcmuio_attach()
returned an error, so `dev->private` might be `NULL`. Check for that
before dereferencing it.
Also, as pointed out by Dan Carpenter, there is no need to check the
pointer passed to `kfree()` is non-NULL, so remove that check.
Signed-off-by: Ian Abbott <abbotti@mev.co.uk>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | drivers/staging/comedi/drivers/pcmuio.c | 11 |
1 files changed, 6 insertions, 5 deletions
diff --git a/drivers/staging/comedi/drivers/pcmuio.c b/drivers/staging/comedi/drivers/pcmuio.c index 0c98e26bbba..b5ed093e59c 100644 --- a/drivers/staging/comedi/drivers/pcmuio.c +++ b/drivers/staging/comedi/drivers/pcmuio.c @@ -935,12 +935,13 @@ static void pcmuio_detach(struct comedi_device *dev) struct pcmuio_private *devpriv = dev->private; int i; - for (i = 0; i < MAX_ASICS; ++i) { - if (devpriv->asics[i].irq) - free_irq(devpriv->asics[i].irq, dev); - } - if (devpriv && devpriv->sprivs) + if (devpriv) { + for (i = 0; i < MAX_ASICS; ++i) { + if (devpriv->asics[i].irq) + free_irq(devpriv->asics[i].irq, dev); + } kfree(devpriv->sprivs); + } comedi_legacy_detach(dev); } |