From fd5d7947f614d837cb3b08e132a025c4e1536d37 Mon Sep 17 00:00:00 2001
From: lat9nq <22451773+lat9nq@users.noreply.github.com>
Date: Tue, 20 Jun 2023 15:49:47 -0400
Subject: [PATCH 1/2] time_zone_manager: Stop on comma

This is a deviation from the reference time zone implementation. The
actual code will set a pointer to the time zone name here, but for us we
have a limited number of characters to work with, and the name of the
time zone here could be larger than 8 characters.

We can make the assumption that time zone names greater than five
characters in length include a comma that denotes more data. Nintendo
just truncates that data for the name, so we can do the same.

time_zone_manager: Check for length of array

Just to be double sure that we never break past the array length,
directly compare against it.
---
 src/core/hle/service/time/time_zone_manager.cpp | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/src/core/hle/service/time/time_zone_manager.cpp b/src/core/hle/service/time/time_zone_manager.cpp
index 63aacd19f..43d0a19b8 100644
--- a/src/core/hle/service/time/time_zone_manager.cpp
+++ b/src/core/hle/service/time/time_zone_manager.cpp
@@ -911,7 +911,9 @@ static Result ToCalendarTimeInternal(const TimeZoneRule& rules, s64 time,
 
     calendar_additional_info.is_dst = rules.ttis[tti_index].is_dst;
     const char* time_zone{&rules.chars[rules.ttis[tti_index].abbreviation_list_index]};
-    for (int index{}; time_zone[index] != '\0'; ++index) {
+    for (u32 index{}; time_zone[index] != '\0' && time_zone[index] != ',' &&
+                      index < calendar_additional_info.timezone_name.size() - 1;
+         ++index) {
         calendar_additional_info.timezone_name[index] = time_zone[index];
     }
     return ResultSuccess;

From ae1a8a7dc7bbe656d9abac646472df2ccf1660db Mon Sep 17 00:00:00 2001
From: lat9nq <22451773+lat9nq@users.noreply.github.com>
Date: Tue, 20 Jun 2023 15:52:17 -0400
Subject: [PATCH 2/2] time_zone_manager: Add null terminator

We aren't null-terminating this string after the copy, and we need to.
---
 src/core/hle/service/time/time_zone_manager.cpp | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/src/core/hle/service/time/time_zone_manager.cpp b/src/core/hle/service/time/time_zone_manager.cpp
index 43d0a19b8..205371a26 100644
--- a/src/core/hle/service/time/time_zone_manager.cpp
+++ b/src/core/hle/service/time/time_zone_manager.cpp
@@ -911,11 +911,13 @@ static Result ToCalendarTimeInternal(const TimeZoneRule& rules, s64 time,
 
     calendar_additional_info.is_dst = rules.ttis[tti_index].is_dst;
     const char* time_zone{&rules.chars[rules.ttis[tti_index].abbreviation_list_index]};
-    for (u32 index{}; time_zone[index] != '\0' && time_zone[index] != ',' &&
-                      index < calendar_additional_info.timezone_name.size() - 1;
+    u32 index;
+    for (index = 0; time_zone[index] != '\0' && time_zone[index] != ',' &&
+                    index < calendar_additional_info.timezone_name.size() - 1;
          ++index) {
         calendar_additional_info.timezone_name[index] = time_zone[index];
     }
+    calendar_additional_info.timezone_name[index] = '\0';
     return ResultSuccess;
 }