Fix security (#655)

* fix, some warning

* fix alerts

examples/tm_yolofastest.cpp

@@ -454,7 +454,7 @@ static void run_yolo(graph_t graph, std::vector<BBoxRect> &boxes, int img_width,
     bool letterbox = false;
     float roi_left = 0.f, roi_top = 0.f, roi_width = 1.f, roi_height = 1.f;
 
-    if (true == letterbox)
+    if (letterbox)
     {
         if (img_width > img_height)
         {

examples/tm_yolov5s_timvx.cpp

@@ -294,7 +294,7 @@ void get_input_data_focus_uint8(const char* image_file, uint8_t* input_data, int
 
     img_new.convertTo(img_new, CV_32FC3);
     float* img_data   = (float* )img_new.data;
-    float* input_temp = (float* )malloc(3 * letterbox_cols * letterbox_rows * sizeof(float));
+    float* input_temp = (float* )malloc(3 * (size_t)letterbox_cols * letterbox_rows * sizeof(float));
 
     /* nhwc to nchw */
     for (int h = 0; h < letterbox_rows; h++)

source/device/cpu/op/conv/x86/conv_dw_kernel_x86.c

@@ -2565,7 +2565,7 @@ int conv_dw_run(struct tensor* input_tensor, struct tensor* weight_tensor, struc
         input_tmp = input;
     else
     {
-        input_tmp = ( float* )sys_malloc(inh_tmp * inw_tmp * group * sizeof(float));
+        input_tmp = ( float* )sys_malloc((size_t)inh_tmp * inw_tmp * group * sizeof(float));
 #pragma omp parallel for num_threads(num_thread)        
         for (int g = 0; g < group; g++)
         {

source/device/cpu/op/pooling/x86/pooling_pack_hcl_x86.h

@@ -1716,7 +1716,7 @@ static void pack4(float* input, float* input_buffer, int in_h, int in_w)
         {
             for (int c = 0; c < PACK4; c++)
             {
-                input_buffer[i * in_w * PACK4 + j * PACK4 + c] = input[c * in_w * in_h + i * in_w + j];
+                input_buffer[i * in_w * PACK4 + j * PACK4 + c] = input[(unsigned long)c * in_w * in_h + i * in_w + j];
             }
         }
     }

source/device/cpu/op/rnn/rnn_ref.c

@@ -223,7 +223,7 @@ static int run(struct node_ops* node_ops, struct exec_node* exec_node, struct ex
     int batch_size = input_tensor->dims[1];
     int output_len = rnn_param->output_len;
 
-    float* init_h = ( float* )malloc(batch_size * hidden_size * sizeof(float));
+    float* init_h = ( float* )malloc((size_t)batch_size * hidden_size * sizeof(float));
     if (init_h == NULL)
     {
         return -1;