From 681066ec1d41e4b299146bada52cef846b323c04 Mon Sep 17 00:00:00 2001 From: Christian König Date: Tue, 27 Feb 2018 12:49:56 +0100 Subject: drm/prime: fix potential race in drm_gem_map_detach MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Unpin the GEM object only after freeing the sg table. Signed-off-by: Christian König Reviewed-by: Daniel Vetter Acked-by: Roger He Signed-off-by: Alex Deucher Link: https://patchwork.freedesktop.org/patch/msgid/20180227115000.4105-1-christian.koenig@amd.com --- drivers/gpu/drm/drm_prime.c | 32 ++++++++++++++++---------------- 1 file changed, 16 insertions(+), 16 deletions(-) (limited to 'drivers/gpu/drm/drm_prime.c') diff --git a/drivers/gpu/drm/drm_prime.c b/drivers/gpu/drm/drm_prime.c index e82a976f0fba..c38dacda6119 100644 --- a/drivers/gpu/drm/drm_prime.c +++ b/drivers/gpu/drm/drm_prime.c @@ -230,26 +230,26 @@ void drm_gem_map_detach(struct dma_buf *dma_buf, struct drm_prime_attachment *prime_attach = attach->priv; struct drm_gem_object *obj = dma_buf->priv; struct drm_device *dev = obj->dev; - struct sg_table *sgt; - if (dev->driver->gem_prime_unpin) - dev->driver->gem_prime_unpin(obj); + if (prime_attach) { + struct sg_table *sgt = prime_attach->sgt; - if (!prime_attach) - return; - - sgt = prime_attach->sgt; - if (sgt) { - if (prime_attach->dir != DMA_NONE) - dma_unmap_sg_attrs(attach->dev, sgt->sgl, sgt->nents, - prime_attach->dir, - DMA_ATTR_SKIP_CPU_SYNC); - sg_free_table(sgt); + if (sgt) { + if (prime_attach->dir != DMA_NONE) + dma_unmap_sg_attrs(attach->dev, sgt->sgl, + sgt->nents, + prime_attach->dir, + DMA_ATTR_SKIP_CPU_SYNC); + sg_free_table(sgt); + } + + kfree(sgt); + kfree(prime_attach); + attach->priv = NULL; } - kfree(sgt); - kfree(prime_attach); - attach->priv = NULL; + if (dev->driver->gem_prime_unpin) + dev->driver->gem_prime_unpin(obj); } EXPORT_SYMBOL(drm_gem_map_detach); -- cgit