SERVER-62205 Check maxChunkSize parameter in (auto)splitVector requests

3 files changed, 13 insertions, 1 deletions

diff --git a/jstests/sharding/libs/mongos_api_params_util.js b/jstests/sharding/libs/mongos_api_params_util.js
index 4f144479c62..63e4f3e1ae4 100644
--- a/jstests/sharding/libs/mongos_api_params_util.js
+++ b/jstests/sharding/libs/mongos_api_params_util.js
@@ -1258,7 +1258,7 @@ let MongosAPIParametersUtil = (function() {
                     keyPattern: {_id: 1},
                     min: {_id: 0},
                     max: {_id: MaxKey},
-                    maxChunkSizeBytes: 1024
+                    maxChunkSizeBytes: 1024 * 1024
                 })
             }
         },
diff --git a/src/mongo/db/s/auto_split_vector_command.cpp b/src/mongo/db/s/auto_split_vector_command.cpp
index 32275403eff..1dd6b15df10 100644
--- a/src/mongo/db/s/auto_split_vector_command.cpp
+++ b/src/mongo/db/s/auto_split_vector_command.cpp
@@ -39,6 +39,8 @@
 namespace mongo {
 namespace {
 
+static constexpr int64_t kSmallestChunkSizeSupported = 1024 * 1024;
+
 class AutoSplitVectorCommand final : public TypedCommand<AutoSplitVectorCommand> {
 public:
     AllowedOnSecondary secondaryAllowed(ServiceContext*) const override {
@@ -67,6 +69,11 @@ public:
 
             const auto& req = request();
 
+            uassert(ErrorCodes::ErrorCodes::InvalidOptions,
+                    str::stream() << "maxChunksSizeBytes cannot be smaller than "
+                                  << kSmallestChunkSizeSupported,
+                    req.getMaxChunkSizeBytes() >= kSmallestChunkSizeSupported);
+
             auto splitKeys = autoSplitVector(opCtx,
                                              ns(),
                                              req.getKeyPattern(),
diff --git a/src/mongo/db/s/split_vector_command.cpp b/src/mongo/db/s/split_vector_command.cpp
index 6efe68ca5f2..3d2ba885bb7 100644
--- a/src/mongo/db/s/split_vector_command.cpp
+++ b/src/mongo/db/s/split_vector_command.cpp
@@ -133,6 +133,11 @@ public:
             maxChunkSizeBytes = maxSizeBytesElem.numberLong();
         }
 
+        if (maxChunkSizeBytes.is_initialized() && *maxChunkSizeBytes < 1024 * 1024) {
+            errmsg = "maxChunkSize must be at least 1MB";
+            return false;
+        }
+
         auto splitKeys = splitVector(opCtx,
                                      nss,
                                      keyPattern,