[gnome-remote-desktop/wip/memcpy-rowstride-fix: 1/2] vnc-pipewire-stream: Correct memcpy size calculation

[Ray Strode <halfline src gnome org>]

commit 8c41590dfd46050da565e2ea20af7dd7a8a56c3e
Author: Ray Strode <rstrode redhat com>
Date:   Thu Aug 27 14:04:03 2020 -0400

    vnc-pipewire-stream: Correct memcpy size calculation
    
    commit 78c5bcb181fe2b0b9fc17eea696feac8b504df54 introduced code
    to try to account for a row stride mismatch between source and
    destination.
    
    That commit, however, erroneously copies destination stride bytes
    from the source, which will lead to out of bounds access if the
    source has a smaller row stride.
    
    This commit addresses the problem, by instead, copying just the
    pixel data, and none of the row margin.
    
    https://gitlab.gnome.org/GNOME/gnome-remote-desktop/-/merge_requests/18

 src/grd-vnc-pipewire-stream.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)
---
diff --git a/src/grd-vnc-pipewire-stream.c b/src/grd-vnc-pipewire-stream.c
index 046c32d..ace2b5d 100644
--- a/src/grd-vnc-pipewire-stream.c
+++ b/src/grd-vnc-pipewire-stream.c
@@ -314,19 +314,21 @@ process_buffer (GrdVncPipeWireStream *stream,
     {
       int src_stride;
       int dst_stride;
+      int width;
       int height;
       int y;
 
       src_stride = buffer->datas[0].chunk->stride;
       dst_stride = grd_session_vnc_get_framebuffer_stride (stream->session);
       height = stream->spa_format.size.height;
+      width = stream->spa_format.size.width;
 
       frame->data = g_malloc (height * dst_stride);
       for (y = 0; y < height; y++)
         {
           memcpy (((uint8_t *) frame->data) + y * dst_stride,
                   ((uint8_t *) src_data) + y * src_stride,
-                  dst_stride);
+                  width * 4);
         }
     }