diff --git a/src/ops.c b/src/ops.c
index 0f42dea..5c58e52 100644
--- a/src/ops.c
+++ b/src/ops.c
@@ -396,7 +396,10 @@
 	return;
 
     /* total is number of screen columns to be inserted/removed */
-    total = amount * p_sw;
+    total = (int)((unsigned)amount * (unsigned)p_sw);
+    if ((total / p_sw) != amount)
+	return; /* multiplication overflow */
+
     oldp = ml_get_curline();
 
     if (!left)
diff --git a/src/testdir/test_visual.vim b/src/testdir/test_visual.vim
index 371fab5..97b884f 100644
--- a/src/testdir/test_visual.vim
+++ b/src/testdir/test_visual.vim
@@ -18,6 +18,14 @@
   q!
 endfunc
 
+func Test_block_shift_overflow()
+  " This used to cause a multiplication overflow followed by a crash.
+  new
+  normal ii
+  exe "normal \<C-V>876543210>"
+  q!
+endfunc
+
 func Test_dotregister_paste()
   new
   exe "norm! ihello world\<esc>"
diff --git a/src/version.c b/src/version.c
index de89ce4..784f6c1 100644
--- a/src/version.c
+++ b/src/version.c
@@ -770,6 +770,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    879,
+/**/
     878,
 /**/
     877,