From 053a33d24df939d1c35f3b6f233a0c57ac185184 Mon Sep 17 00:00:00 2001
From: Shahar Mike <chakaz@users.noreply.github.com>
Date: Mon, 6 Nov 2023 13:31:23 +0200
Subject: [PATCH] fix(rename-command): Fix subtle UB when renaming commands
 (#2132)

In practive, commands larger than SSO would not work.

Fixes #2131
---
 src/server/command_registry.cc |  2 +-
 src/server/dragonfly_test.cc   | 25 +++++++++++++++----------
 2 files changed, 16 insertions(+), 11 deletions(-)

diff --git a/src/server/command_registry.cc b/src/server/command_registry.cc
index 5e3483acf..fc1eae083 100644
--- a/src/server/command_registry.cc
+++ b/src/server/command_registry.cc
@@ -117,7 +117,7 @@ void CommandRegistry::Init(unsigned int thread_count) {
 }
 
 CommandRegistry& CommandRegistry::operator<<(CommandId cmd) {
-  auto k = cmd.name();
+  string k = string(cmd.name());
 
   absl::InlinedVector<std::string_view, 2> maybe_subcommand = StrSplit(cmd.name(), " ");
   const bool is_sub_command = maybe_subcommand.size() == 2;
diff --git a/src/server/dragonfly_test.cc b/src/server/dragonfly_test.cc
index cde768de9..507d89c27 100644
--- a/src/server/dragonfly_test.cc
+++ b/src/server/dragonfly_test.cc
@@ -99,8 +99,9 @@ class DflyRenameCommandTest : public DflyEngineTest {
  protected:
   DflyRenameCommandTest() : DflyEngineTest() {
     // rename flushall to myflushall, flushdb command will not be able to execute
-    absl::SetFlag(&FLAGS_rename_command,
-                  std::vector<std::string>({"flushall=myflushall", "flushdb="}));
+    absl::SetFlag(
+        &FLAGS_rename_command,
+        std::vector<std::string>({"flushall=myflushall", "flushdb=", "ping=abcdefghijklmnop"}));
   }
 
   void TearDown() {
@@ -113,16 +114,20 @@ TEST_F(DflyRenameCommandTest, RenameCommand) {
   Run({"set", "a", "1"});
   ASSERT_EQ(1, CheckedInt({"dbsize"}));
   // flushall should not execute anything and should return error, as it was renamed.
-  RespExpr resp = Run({"flushall"});
-  ASSERT_THAT(resp, ErrArg("unknown command `FLUSHALL`"));
+  ASSERT_THAT(Run({"flushall"}), ErrArg("unknown command `FLUSHALL`"));
+
   ASSERT_EQ(1, CheckedInt({"dbsize"}));
-  resp = Run({"myflushall"});
-  ASSERT_EQ(resp, "OK");
+
+  ASSERT_EQ(Run({"myflushall"}), "OK");
+
   ASSERT_EQ(0, CheckedInt({"dbsize"}));
-  resp = Run({"flushdb", "0"});
-  ASSERT_THAT(resp, ErrArg("unknown command `FLUSHDB`"));
-  resp = Run({""});
-  ASSERT_THAT(resp, ErrArg("unknown command ``"));
+
+  ASSERT_THAT(Run({"flushdb", "0"}), ErrArg("unknown command `FLUSHDB`"));
+
+  ASSERT_THAT(Run({""}), ErrArg("unknown command ``"));
+
+  ASSERT_THAT(Run({"ping"}), ErrArg("unknown command `PING`"));
+  ASSERT_THAT(Run({"abcdefghijklmnop"}), "PONG");
 }
 
 TEST_F(SingleThreadDflyEngineTest, GlobalSingleThread) {