From fca9448ae2f5ddebd841c727ee86136e1b5cbd86 Mon Sep 17 00:00:00 2001
From: Dan Carpenter <dan.carpenter@linaro.org>
Date: Wed, 6 Dec 2023 17:37:24 +0300
Subject: [PATCH] drm/imagination: Move dereference after NULL check in
pvr_mmu_backing_page_init()
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>
Signed-off-by: Maxime Ripard <mripard@kernel.org>
Link: https://patchwork.freedesktop.org/patch/msgid/13f4278e-af9c-4092-9196-bc0e6b76f1eb@moroto.mountain
---
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);
--
GitLab