From ab13cd992405f84dc48b7d49b54c5de06a7cd5ab Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Felf=C3=B6ldi=20Zsolt?= <zsfelfoldi@gmail.com>
Date: Fri, 21 Sep 2018 09:59:21 +0200
Subject: [PATCH] les: fix invalid delivery handling in retriever (#17727)

---
 les/retrieve.go | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/les/retrieve.go b/les/retrieve.go
index c3d788813..d77cfea74 100644
--- a/les/retrieve.go
+++ b/les/retrieve.go
@@ -212,11 +212,18 @@ func (r *sentReq) stateRequesting() reqStateFn {
 				// no need to go to stopped state because waiting() already returned false
 				return nil
 			}
-		case rpSoftTimeout, rpDeliveredInvalid:
+		case rpSoftTimeout:
 			// last request timed out, try asking a new peer
 			go r.tryRequest()
 			r.lastReqQueued = true
 			return r.stateRequesting
+		case rpDeliveredInvalid:
+			// if it was the last sent request (set to nil by update) then start a new one
+			if !r.lastReqQueued && r.lastReqSentTo == nil {
+				go r.tryRequest()
+				r.lastReqQueued = true
+			}
+			return r.stateRequesting
 		case rpDeliveredValid:
 			r.stop(nil)
 			return r.stateStopped