| Message ID | 13f4278e-af9c-4092-9196-bc0e6b76f1eb@moroto.mountain (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | drm/imagination: Move dereference after NULL check in pvr_mmu_backing_page_init() | expand |
Hi Dan, Thank you for the patch. On Wed, 2023-12-06 at 17:37 +0300, Dan Carpenter wrote: > This code dereferences "page->pvr_dev" and then checked for NULL on the > next line. Re-order it to avoid a potential NULL pointer dereference. > > Fixes: ff5f643de0bf ("drm/imagination: Add GEM and VM related code") > Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org> Reviewed-by: Frank Binns <frank.binns@imgtec.com> > --- > drivers/gpu/drm/imagination/pvr_mmu.c | 4 +++- > 1 file changed, 3 insertions(+), 1 deletion(-) > > diff --git a/drivers/gpu/drm/imagination/pvr_mmu.c b/drivers/gpu/drm/imagination/pvr_mmu.c > index c8562bfc0dcd..4fe70610ed94 100644 > --- a/drivers/gpu/drm/imagination/pvr_mmu.c > +++ b/drivers/gpu/drm/imagination/pvr_mmu.c > @@ -316,12 +316,14 @@ pvr_mmu_backing_page_init(struct pvr_mmu_backing_page *page, > static void > pvr_mmu_backing_page_fini(struct pvr_mmu_backing_page *page) > { > - struct device *dev = from_pvr_device(page->pvr_dev)->dev; > + struct device *dev; > > /* Do nothing if no allocation is present. */ > if (!page->pvr_dev) > return; > > + dev = from_pvr_device(page->pvr_dev)->dev; > + > dma_unmap_page(dev, page->dma_addr, PVR_MMU_BACKING_PAGE_SIZE, > DMA_TO_DEVICE); >
On Wed, 06 Dec 2023 17:37:24 +0300, Dan Carpenter wrote: > This code dereferences "page->pvr_dev" and then checked for NULL on the > next line. Re-order it to avoid a potential NULL pointer dereference. > > Applied to drm/drm-misc (drm-misc-next). Thanks! Maxime
diff --git a/drivers/gpu/drm/imagination/pvr_mmu.c b/drivers/gpu/drm/imagination/pvr_mmu.c index c8562bfc0dcd..4fe70610ed94 100644 --- a/drivers/gpu/drm/imagination/pvr_mmu.c +++ b/drivers/gpu/drm/imagination/pvr_mmu.c @@ -316,12 +316,14 @@ pvr_mmu_backing_page_init(struct pvr_mmu_backing_page *page, static void pvr_mmu_backing_page_fini(struct pvr_mmu_backing_page *page) { - struct device *dev = from_pvr_device(page->pvr_dev)->dev; + struct device *dev; /* Do nothing if no allocation is present. */ if (!page->pvr_dev) return; + dev = from_pvr_device(page->pvr_dev)->dev; + dma_unmap_page(dev, page->dma_addr, PVR_MMU_BACKING_PAGE_SIZE, DMA_TO_DEVICE);
This code dereferences "page->pvr_dev" and then checked for NULL on the next line. Re-order it to avoid a potential NULL pointer dereference. Fixes: ff5f643de0bf ("drm/imagination: Add GEM and VM related code") Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org> --- drivers/gpu/drm/imagination/pvr_mmu.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-)