diff --git a/sys/cam/ctl/ctl.c b/sys/cam/ctl/ctl.c
index 88337523946a..8d85bc55a6a4 100644
--- a/sys/cam/ctl/ctl.c
+++ b/sys/cam/ctl/ctl.c
@@ -5808,9 +5808,8 @@ ctl_write_same(struct ctl_scsiio *ctsio)
 		break; /* NOTREACHED */
 	}
 
-	/* NDOB and ANCHOR flags can be used only together with UNMAP */
-	if ((byte2 & SWS_UNMAP) == 0 &&
-	    (byte2 & (SWS_NDOB | SWS_ANCHOR)) != 0) {
+	/* ANCHOR flag can be used only together with UNMAP */
+	if ((byte2 & SWS_UNMAP) == 0 && (byte2 & SWS_ANCHOR) != 0) {
 		ctl_set_invalid_field(ctsio, /*sks_valid*/ 1,
 		    /*command*/ 1, /*field*/ 1, /*bit_valid*/ 1, /*bit*/ 0);
 		ctl_done((union ctl_io *)ctsio);
diff --git a/sys/cam/ctl/ctl_backend_block.c b/sys/cam/ctl/ctl_backend_block.c
index 2ef5598de6f9..a37ac7bd05bf 100644
--- a/sys/cam/ctl/ctl_backend_block.c
+++ b/sys/cam/ctl/ctl_backend_block.c
@@ -1357,7 +1357,12 @@ ctl_be_block_cw_dispatch_ws(struct ctl_be_block_lun *be_lun,
 		buf = beio->sg_segs[i].addr;
 		end = buf + seglen;
 		for (; buf < end; buf += cbe_lun->blocksize) {
-			memcpy(buf, io->scsiio.kern_data_ptr, cbe_lun->blocksize);
+			if (lbalen->flags & SWS_NDOB) {
+				memset(buf, 0, cbe_lun->blocksize);
+			} else {
+				memcpy(buf, io->scsiio.kern_data_ptr,
+				    cbe_lun->blocksize);
+			}
 			if (lbalen->flags & SWS_LBDATA)
 				scsi_ulto4b(lbalen->lba + lba, buf);
 			lba++;