diff --git a/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dmu_send.c b/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dmu_send.c
index 81fd9f29f4fd..0b8cc6267b8a 100644
--- a/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dmu_send.c
+++ b/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dmu_send.c
@@ -93,6 +93,9 @@ dump_free(dmu_sendarg_t *dsp, uint64_t object, uint64_t offset,
 {
 	struct drr_free *drrf = &(dsp->dsa_drr->drr_u.drr_free);
 
+	if (length != -1ULL && offset + length < offset)
+		length = -1ULL;
+
 	/*
 	 * If there is a pending op, but it's not PENDING_FREE, push it out,
 	 * since free block aggregation can only be done for blocks of the