bugfix: usage of nil in Connection.peekFuture()

It may be possible to get a nil value from conn.getFutureImp(). We need
to check the value before using.

Author: oleg-jukovec

CHANGELOG.md

@@ -34,6 +34,7 @@ Versioning](http://semver.org/spec/v2.0.0.html) except to the first release.
 - Build with OpenSSL < 1.1.1 (#194)
 - Add `ExecuteAsync` and `ExecuteTyped` to common connector interface (#62)
 - Race conditions in methods of `Future` type (#195)
+- Usage of nil pointer in Connection.peekFuture (#195)
 
 ## [1.6.0] - 2022-06-01
 

connection.go

@@ -949,11 +949,12 @@ func (conn *Connection) peekFuture(reqid uint32) (fut *Future) {
 	defer shard.rmut.Unlock()
 
 	if conn.opts.Timeout > 0 {
-		fut = conn.getFutureImp(reqid, true)
-		pair := &shard.requests[pos]
-		*pair.last = fut
-		pair.last = &fut.next
-		fut.timeout = time.Since(epoch) + conn.opts.Timeout
+		if fut = conn.getFutureImp(reqid, true); fut != nil {
+			pair := &shard.requests[pos]
+			*pair.last = fut
+			pair.last = &fut.next
+			fut.timeout = time.Since(epoch) + conn.opts.Timeout
+		}
 	} else {
 		fut = conn.getFutureImp(reqid, false)
 	}