set: Fixed GetAvailableLanguageCodes() to follow the max_entries

Rightnow, in games use GetAvailableLanguageCodes(), there is a WriteBuffer() with size larger than the buffer_size. (Core Critical core\hle\kernel\hle_ipc.cpp:WriteBuffer:296: size (0000000000000088) is greater than buffer_size (0000000000000078))

0x88 = 17(languages) * 8
0x78 = 15(languages) * 8

GetAvailableLanguageCodes() can only support 15 languages.
After firmware 4.0.0 there are 17 supported language instead of 15, to enable this GetAvailableLanguageCodes2() need to be used.
So GetAvailableLanguageCodes() will be caped at 15 languages.
Reference:
http://switchbrew.org/index.php/Settings_services

2 files changed, 45 insertions, 8 deletions

diff --git a/src/core/hle/service/set/set.cpp b/src/core/hle/service/set/set.cpp
index a461e72ec..92b0640e8 100644
--- a/src/core/hle/service/set/set.cpp
+++ b/src/core/hle/service/set/set.cpp
@@ -32,24 +32,59 @@ constexpr std::array<LanguageCode, 17> available_language_codes = {{
     LanguageCode::ZH_HANT,
 }};
 
+constexpr size_t pre4_0_0_max_entries = 0xF;
+constexpr size_t post4_0_0_max_entries = 0x40;
+
 LanguageCode GetLanguageCodeFromIndex(size_t index) {
     return available_language_codes.at(index);
 }
 
-void SET::GetAvailableLanguageCodes(Kernel::HLERequestContext& ctx) {
-    ctx.WriteBuffer(available_language_codes);
+template <size_t size>
+static std::array<LanguageCode, size> MakeLanguageCodeSubset() {
+    std::array<LanguageCode, size> arr;
+    std::copy_n(available_language_codes.begin(), size, arr.begin());
+    return arr;
+}
 
+static void PushResponseLanguageCode(Kernel::HLERequestContext& ctx, size_t max_size) {
     IPC::ResponseBuilder rb{ctx, 3};
     rb.Push(RESULT_SUCCESS);
-    rb.Push(static_cast<u32>(available_language_codes.size()));
+    if (available_language_codes.size() > max_size)
+        rb.Push(static_cast<u32>(max_size));
+    else
+        rb.Push(static_cast<u32>(available_language_codes.size()));
+}
+
+void SET::GetAvailableLanguageCodes(Kernel::HLERequestContext& ctx) {
+    if (available_language_codes.size() > pre4_0_0_max_entries)
+        ctx.WriteBuffer(MakeLanguageCodeSubset<pre4_0_0_max_entries>());
+    else
+        ctx.WriteBuffer(available_language_codes);
+
+    PushResponseLanguageCode(ctx, pre4_0_0_max_entries);
+
+    LOG_DEBUG(Service_SET, "called");
+}
+
+void SET::GetAvailableLanguageCodes2(Kernel::HLERequestContext& ctx) {
+    if (available_language_codes.size() > post4_0_0_max_entries)
+        ctx.WriteBuffer(MakeLanguageCodeSubset<post4_0_0_max_entries>());
+    else
+        ctx.WriteBuffer(available_language_codes);
+
+    PushResponseLanguageCode(ctx, post4_0_0_max_entries);
 
     LOG_DEBUG(Service_SET, "called");
 }
 
 void SET::GetAvailableLanguageCodeCount(Kernel::HLERequestContext& ctx) {
-    IPC::ResponseBuilder rb{ctx, 3};
-    rb.Push(RESULT_SUCCESS);
-    rb.Push(static_cast<u32>(available_language_codes.size()));
+    PushResponseLanguageCode(ctx, pre4_0_0_max_entries);
+
+    LOG_DEBUG(Service_SET, "called");
+}
+
+void SET::GetAvailableLanguageCodeCount2(Kernel::HLERequestContext& ctx) {
+    PushResponseLanguageCode(ctx, post4_0_0_max_entries);
 
     LOG_DEBUG(Service_SET, "called");
 }
@@ -69,8 +104,8 @@ SET::SET() : ServiceFramework("set") {
         {2, nullptr, "MakeLanguageCode"},
         {3, &SET::GetAvailableLanguageCodeCount, "GetAvailableLanguageCodeCount"},
         {4, nullptr, "GetRegionCode"},
-        {5, &SET::GetAvailableLanguageCodes, "GetAvailableLanguageCodes2"},
-        {6, &SET::GetAvailableLanguageCodeCount, "GetAvailableLanguageCodeCount2"},
+        {5, &SET::GetAvailableLanguageCodes2, "GetAvailableLanguageCodes2"},
+        {6, &SET::GetAvailableLanguageCodeCount2, "GetAvailableLanguageCodeCount2"},
         {7, nullptr, "GetKeyCodeMap"},
         {8, nullptr, "GetQuestFlag"},
     };
diff --git a/src/core/hle/service/set/set.h b/src/core/hle/service/set/set.h
index 4232b6162..669e740b7 100644
--- a/src/core/hle/service/set/set.h
+++ b/src/core/hle/service/set/set.h
@@ -38,7 +38,9 @@ public:
 private:
     void GetLanguageCode(Kernel::HLERequestContext& ctx);
     void GetAvailableLanguageCodes(Kernel::HLERequestContext& ctx);
+    void GetAvailableLanguageCodes2(Kernel::HLERequestContext& ctx);
     void GetAvailableLanguageCodeCount(Kernel::HLERequestContext& ctx);
+    void GetAvailableLanguageCodeCount2(Kernel::HLERequestContext& ctx);
 };
 
 } // namespace Service::Set