[PATCH 6.1 284/609] drm/amdgpu: fix division by zero with invalid uvd dimensions

6.1-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Boyuan Zhang <[email protected]>

commit 0c01c811be47e6b146552dd59bfedbea8f09b8f4 upstream.

When width or height is less than 16, width_in_mb or height_in_mb
becomes 0, leading to fs_in_mb being 0. This causes a division by
zero when calculating num_dpb_buffer in H264 and H264 Perf decode
paths.

Add validation to reject frames with width < 16 or height < 16
before performing any calculations that depend on these values.

V2: Format change - move up all vaiable definitions.
V3: Use warn_once to avoid spam.

Signed-off-by: Boyuan Zhang <[email protected]>
Reviewed-by: Leo Liu <[email protected]>
Reviewed-by: Alex Deucher <[email protected]>
Signed-off-by: Alex Deucher <[email protected]>
(cherry picked from commit 3e41d26c70b0a459d041cc19482a226c4b7423cb)
Cc: [email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>
---
 drivers/gpu/drm/amd/amdgpu/amdgpu_uvd.c |    8 ++++++++
 1 file changed, 8 insertions(+)

--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_uvd.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_uvd.c
@@ -630,6 +630,14 @@ static int amdgpu_uvd_cs_msg_decode(stru
 	unsigned image_size, tmp, min_dpb_size, num_dpb_buffer;
 	unsigned min_ctx_size = ~0;
 
+	/* Reject invalid dimensions to prevent division by zero */
+	if (width < 16 || height < 16) {
+		dev_WARN_ONCE(adev->dev, 1,
+			      "Invalid UVD decoding dimensions (%dx%d)!\n",
+			      width, height);
+		return -EINVAL;
+	}
+
 	image_size = width * height;
 	image_size += image_size / 2;
 	image_size = ALIGN(image_size, 1024);