diff --git a/src/target/target.c b/src/target/target.c
index a0da26c..e433bdb 100644
--- a/src/target/target.c
+++ b/src/target/target.c
@@ -199,7 +199,8 @@ int target_flash_erase(target *t, target_addr addr, size_t len)
 	int ret = 0;
 	while (len) {
 		struct target_flash *f = flash_for_addr(t, addr);
-		size_t tmplen = MIN(len, f->length - (addr % f->length));
+		size_t tmptarget = MIN(addr + len, f->start + f->length);
+		size_t tmplen = tmptarget - addr;
 		ret |= f->erase(f, addr, tmplen);
 		addr += tmplen;
 		len -= tmplen;