From 0ba9ea6a3b98d6454164ac12a29baef30f1ef595 Mon Sep 17 00:00:00 2001
From: Stephen Miller <56742918+StevenMiller123@users.noreply.github.com>
Date: Fri, 2 May 2025 13:22:05 -0500
Subject: [PATCH] Only perform early read-write open when truncating is needed
 (#2874)

Should stop some fs error spam when games open files from /app0, as this open call would fail from reduced permissions.
---
 src/core/libraries/kernel/file_system.cpp | 15 ++++++++-------
 1 file changed, 8 insertions(+), 7 deletions(-)

diff --git a/src/core/libraries/kernel/file_system.cpp b/src/core/libraries/kernel/file_system.cpp
index cb1fd14a2..ad372325c 100644
--- a/src/core/libraries/kernel/file_system.cpp
+++ b/src/core/libraries/kernel/file_system.cpp
@@ -181,10 +181,6 @@ s32 PS4_SYSV_ABI open(const char* raw_path, s32 flags, u16 mode) {
             return -1;
         }
     } else {
-        // Start by opening as read-write so we can truncate regardless of flags.
-        // Since open starts by closing the file, this won't interfere with later open calls.
-        e = file->f.Open(file->m_host_name, Common::FS::FileAccessMode::ReadWrite);
-
         file->type = Core::FileSys::FileType::Regular;
 
         if (truncate && read_only) {
@@ -192,9 +188,14 @@ s32 PS4_SYSV_ABI open(const char* raw_path, s32 flags, u16 mode) {
             h->DeleteHandle(handle);
             *__Error() = POSIX_EROFS;
             return -1;
-        } else if (truncate && e == 0) {
-            // If the file was opened successfully and truncate was enabled, reduce size to 0
-            file->f.SetSize(0);
+        } else if (truncate) {
+            // Open the file as read-write so we can truncate regardless of flags.
+            // Since open starts by closing the file, this won't interfere with later open calls.
+            e = file->f.Open(file->m_host_name, Common::FS::FileAccessMode::ReadWrite);
+            if (e == 0) {
+                // If the file was opened successfully, reduce size to 0
+                file->f.SetSize(0);
+            }
         }
 
         if (read) {