*** 75,84 ****
--- 75,87 ----
  dump_free(dmu_sendarg_t *dsp, uint64_t object, uint64_t offset,
      uint64_t length)
  {
          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
           * same type (i.e., DRR_FREE records can only be aggregated with
           * other DRR_FREE records.  DRR_FREEOBJECTS records can only be