File GraphicsMagick-CVE-2020-12672.patch of Package GraphicsMagick

diff -r 4917a4242fc0 -r 50395430a371 coders/png.c
--- a/coders/png.c      Fri May 01 13:49:13 2020 -0500
+++ b/coders/png.c      Sat May 30 10:18:16 2020 -0500
@@ -5689,7 +5691,28 @@
 
               if (logging)
                 (void) LogMagickEvent(CoderEvent,GetMagickModule(),
-                                      "  Processing MNG MAGN chunk");
+                                      "  Processing MNG MAGN chunk: MB=%u, ML=%u,"
+                                      " MR=%u, MT=%u, MX=%u, MY=%u,"
+                                      " X_method=%u, Y_method=%u",
+                                      mng_info->magn_mb,mng_info->magn_ml,
+                                      mng_info->magn_mr,mng_info->magn_mt,
+                                      mng_info->magn_mx,mng_info->magn_my,
+                                      mng_info->magn_methx,
+                                      mng_info->magn_methy);
+
+              /*
+                If the image width is 1, then X magnification is done
+                by simple pixel replication.
+              */
+              if (image->columns == 1)
+                  mng_info->magn_methx = 1;
+
+              /*
+                If the image height is 1, then Y magnification is done
+                by simple pixel replication.
+              */
+              if (image->rows == 1)
+                  mng_info->magn_methy = 1;
 
               if (mng_info->magn_methx == 1)
                 {
@@ -5734,12 +5757,10 @@
                   Image
                     *large_image;
 
-                  int
-                    yy;
-
                   long
                     m,
-                    y;
+                    y,
+                    yy;
 
                   register long
                     x;