--- vdev_raidz.c	2019-02-19 15:46:11.000000000 -0800
+++ vdev_raidz.c	2019-02-19 15:37:29.000000000 -0800
@@ -565,16 +565,13 @@
 	if (!dofree) {
 		for (c = 0; c < rm->rm_firstdatacol; c++) {
 			rm->rm_col[c].rc_abd =
 			    abd_alloc_linear(rm->rm_col[c].rc_size, B_TRUE);
 		}
 
-		rm->rm_col[c].rc_abd = abd_get_offset(abd, 0);
-		off = rm->rm_col[c].rc_size;
-
-		for (c = c + 1; c < acols; c++) {
+		for (off = 0; c < acols; c++) {
 			rm->rm_col[c].rc_abd = abd_get_offset(abd, off);
 			off += rm->rm_col[c].rc_size;
 		}
 	}
 
 	/*