Adds check for negative search request size (#25397)

* Adds check for negative search request size

This change adds a check to `SearchSourceBuilder` to throw and exception if the size set on it is set to a negative value.

Closes #22530

* fix error in reindex

* update re-index tests

* Addresses review comment

* Fixed tests

* Added random negative size test

* Fixes test

2 files changed, 11 insertions, 2 deletions

diff --git a/core/src/main/java/org/elasticsearch/index/reindex/AbstractBulkByScrollRequest.java b/core/src/main/java/org/elasticsearch/index/reindex/AbstractBulkByScrollRequest.java
index 5bfae5fde9..9f10304622 100644
--- a/core/src/main/java/org/elasticsearch/index/reindex/AbstractBulkByScrollRequest.java
+++ b/core/src/main/java/org/elasticsearch/index/reindex/AbstractBulkByScrollRequest.java
@@ -171,6 +171,9 @@ public abstract class AbstractBulkByScrollRequest<Self extends AbstractBulkByScr
      * documents.
      */
     public Self setSize(int size) {
+        if (size < 0) {
+            throw new IllegalArgumentException("[size] parameter cannot be negative, found [" + size + "]");
+        }
         this.size = size;
         return self();
     }
@@ -367,10 +370,13 @@ public abstract class AbstractBulkByScrollRequest<Self extends AbstractBulkByScr
                 .setShouldStoreResult(false)
                 // Split requests per second between all slices
                 .setRequestsPerSecond(requestsPerSecond / slices)
-                // Size is split between workers. This means the size might round down!
-                .setSize(size == SIZE_ALL_MATCHES ? SIZE_ALL_MATCHES : size / slices)
                 // Sub requests don't have workers
                 .setSlices(1);
+        if (size != -1) {
+            // Size is split between workers. This means the size might round
+            // down!
+            request.setSize(size == SIZE_ALL_MATCHES ? SIZE_ALL_MATCHES : size / slices);
+        }
         // Set the parent task so this task is cancelled if we cancel the parent
         request.setParentTask(slicingTask);
         // TODO It'd be nice not to refresh on every slice. Instead we should refresh after the sub requests finish.
diff --git a/core/src/main/java/org/elasticsearch/search/builder/SearchSourceBuilder.java b/core/src/main/java/org/elasticsearch/search/builder/SearchSourceBuilder.java
index 91edc29160..537635895e 100644
--- a/core/src/main/java/org/elasticsearch/search/builder/SearchSourceBuilder.java
+++ b/core/src/main/java/org/elasticsearch/search/builder/SearchSourceBuilder.java
@@ -345,6 +345,9 @@ public final class SearchSourceBuilder extends ToXContentToBytes implements Writ
      * The number of search hits to return. Defaults to <tt>10</tt>.
      */
     public SearchSourceBuilder size(int size) {
+        if (size < 0) {
+            throw new IllegalArgumentException("[size] parameter cannot be negative, found [" + size + "]");
+        }
         this.size = size;
         return this;
     }