Re: [PATCH] media: media/pci: prevent memory leak in bttv_probe
From: butt3rflyh4ck
Date: Fri Apr 17 2020 - 05:45:41 EST
On Fri, Apr 17, 2020 at 3:26 PM Hans Verkuil <hverkuil-cisco@xxxxxxxxx> wrote:
>
> On 25/03/2020 10:01, Xiaolong Huang wrote:
> > In bttv_probe if some functions such as pci_enable_device,
> > pci_set_dma_mask and request_mem_region fails the allocated
> > memory for btv should be released.
> >
> > Signed-off-by: Xiaolong Huang <butterflyhuangxx@xxxxxxxxx>
> > ---
> > drivers/media/pci/bt8xx/bttv-driver.c | 8 ++++++++
> > 1 file changed, 8 insertions(+)
> >
> > diff --git a/drivers/media/pci/bt8xx/bttv-driver.c b/drivers/media/pci/bt8xx/bttv-driver.c
> > index a359da7773a9..37ac59110383 100644
> > --- a/drivers/media/pci/bt8xx/bttv-driver.c
> > +++ b/drivers/media/pci/bt8xx/bttv-driver.c
> > @@ -4013,10 +4013,14 @@ static int bttv_probe(struct pci_dev *dev, const struct pci_device_id *pci_id)
> > btv->id = dev->device;
> > if (pci_enable_device(dev)) {
> > pr_warn("%d: Can't enable device\n", btv->c.nr);
> > + bttvs[btv->c.nr] = NULL;
> > + kfree(btv);
> > return -EIO;
>
> Let's change this...
>
> > }
> > if (pci_set_dma_mask(dev, DMA_BIT_MASK(32))) {
> > pr_warn("%d: No suitable DMA available\n", btv->c.nr);
> > + bttvs[btv->c.nr] = NULL;
> > + kfree(btv);
> > return -EIO;
>
> this...
>
> > }
> > if (!request_mem_region(pci_resource_start(dev,0),
> > @@ -4025,6 +4029,8 @@ static int bttv_probe(struct pci_dev *dev, const struct pci_device_id *pci_id)
> > pr_warn("%d: can't request iomem (0x%llx)\n",
> > btv->c.nr,
> > (unsigned long long)pci_resource_start(dev, 0));
> > + bttvs[btv->c.nr] = NULL;
> > + kfree(btv);
> > return -EBUSY;
>
> and this to a goto free_mem.
>
> > }
> > pci_set_master(dev);
> > @@ -4211,6 +4217,8 @@ static int bttv_probe(struct pci_dev *dev, const struct pci_device_id *pci_id)
> > release_mem_region(pci_resource_start(btv->c.pci,0),
> > pci_resource_len(btv->c.pci,0));
> > pci_disable_device(btv->c.pci);
>
> And add the free_mem: label here.
>
> > + bttvs[btv->c.nr] = NULL;
> > + kfree(btv);
> > return result;
> > }
> >
> >
>
> Regards,
>
> Hans
Good, I will modify the patch and resend a new one.
Thanks,
Butt3flyh4ck