[PATCH AUTOSEL 5.2 076/171] drm/msm/adreno: Ensure that the zap shader region is big enough

[Sasha Levin <sashal@kernel.org>]

From: Jordan Crouse <jcrouse@codeaurora.org>

[ Upstream commit 6672e11cad662ce6631e04c38f92a140a99c042c ]

Before loading the zap shader we should ensure that the reserved memory
region is big enough to hold the loaded file.

Signed-off-by: Jordan Crouse <jcrouse@codeaurora.org>
Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Reviewed-by: Jeffrey Hugo <jeffrey.l.hugo@gmail.com>
Signed-off-by: Rob Clark <robdclark@chromium.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/gpu/drm/msm/adreno/adreno_gpu.c | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/msm/adreno/adreno_gpu.c b/drivers/gpu/drm/msm/adreno/adreno_gpu.c
index a9c0ac937b00..9acbbc0f3232 100644
--- a/drivers/gpu/drm/msm/adreno/adreno_gpu.c
+++ b/drivers/gpu/drm/msm/adreno/adreno_gpu.c
@@ -56,7 +56,6 @@ static int zap_shader_load_mdt(struct msm_gpu *gpu, const char *fwname,
 		return ret;
 
 	mem_phys = r.start;
-	mem_size = resource_size(&r);
 
 	/* Request the MDT file for the firmware */
 	fw = adreno_request_fw(to_adreno_gpu(gpu), fwname);
@@ -72,6 +71,13 @@ static int zap_shader_load_mdt(struct msm_gpu *gpu, const char *fwname,
 		goto out;
 	}
 
+	if (mem_size > resource_size(&r)) {
+		DRM_DEV_ERROR(dev,
+			"memory region is too small to load the MDT\n");
+		ret = -E2BIG;
+		goto out;
+	}
+
 	/* Allocate memory for the firmware image */
 	mem_region = memremap(mem_phys, mem_size,  MEMREMAP_WC);
 	if (!mem_region) {
-- 
2.20.1