Upon failure, dma_alloc_coherent() returns NULL. If that does happen, passing some uninitialised stack contents to dma_mapping_error() - which belongs to a different API in the first place - has precious little chance of detecting it. Also include the correct header, because the fragile transitive inclusion currently providing it is going to break soon. Fixes: 20e7dce255e9 ("drm/tegra: Remove memory allocation from Falcon library") CC: Thierry Reding <thierry.reding@xxxxxxxxx> CC: Mikko Perttunen <mperttunen@xxxxxxxxxx> CC: dri-devel@xxxxxxxxxxxxxxxxxxxxx Signed-off-by: Robin Murphy <robin.murphy@xxxxxxx> --- It also doesn't appear to handle failure of the tegra_drm_alloc() path either, but that's a loose thread I have no desire to pull on... ;) v2: Resend as part of the series, originally posted separately here: https://lore.kernel.org/dri-devel/2703882439344010e33bf21ecd63cf9e5e6dc00d.1637781007.git.robin.murphy@xxxxxxx/ drivers/gpu/drm/tegra/vic.c | 7 +++---- 1 file changed, 3 insertions(+), 4 deletions(-) diff --git a/drivers/gpu/drm/tegra/vic.c b/drivers/gpu/drm/tegra/vic.c index c02010ff2b7f..da4af5371991 100644 --- a/drivers/gpu/drm/tegra/vic.c +++ b/drivers/gpu/drm/tegra/vic.c @@ -5,6 +5,7 @@ #include <linux/clk.h> #include <linux/delay.h> +#include <linux/dma-mapping.h> #include <linux/host1x.h> #include <linux/iommu.h> #include <linux/module.h> @@ -232,10 +233,8 @@ static int vic_load_firmware(struct vic *vic) if (!client->group) { virt = dma_alloc_coherent(vic->dev, size, &iova, GFP_KERNEL); - - err = dma_mapping_error(vic->dev, iova); - if (err < 0) - return err; + if (!virt) + return -ENOMEM; } else { virt = tegra_drm_alloc(tegra, size, &iova); } -- 2.28.0.dirty