diff --git a/dnn/src/cuda/convolution/backward_filter/matmul.cpp b/dnn/src/cuda/convolution/backward_filter/matmul.cpp
index 7d0bbeec..4c4a2253 100644
--- a/dnn/src/cuda/convolution/backward_filter/matmul.cpp
+++ b/dnn/src/cuda/convolution/backward_filter/matmul.cpp
@@ -21,11 +21,11 @@ using namespace cuda;
 
 namespace {
 std::pair<TensorLayoutArray, MatrixMulForward::Param> sub_opr_config(
-        const ConvolutionBackwardDataImpl::CanonizedFilterMeta& fm,
+        const ConvolutionBackwardFilterImpl::CanonizedFilterMeta& fm,
         const TensorLayout& src_layout, const TensorLayout& diff_layout,
         const TensorLayout& grad_layout,
         const ConvolutionBackwardFilterImpl* opr) {
-    size_t N = grad_layout.shape[0], IC = fm.icpg,
+    size_t N = src_layout.shape[0], IC = fm.icpg,
            OC = fm.ocpg, OH = diff_layout.shape[2],
            OW = diff_layout.shape[3], FH = fm.spatial[0],
            FW = fm.spatial[1];