diff --git a/src/core/libraries/libc_internal/libc_internal_io.cpp b/src/core/libraries/libc_internal/libc_internal_io.cpp
index 0d1a8a54f..d4dc712e1 100644
--- a/src/core/libraries/libc_internal/libc_internal_io.cpp
+++ b/src/core/libraries/libc_internal/libc_internal_io.cpp
@@ -76,7 +76,8 @@ OrbisFILE* PS4_SYSV_ABI internal__Foprep(const char* path, const char* mode, Orb
     }
 
     // Preserve mode and index
-    Libraries::Kernel::PthreadMutexT file_mtx = file->_Mutex;
+    Libraries::Kernel::PthreadMutexT mtx = file->_Mutex;
+    Libraries::Kernel::PthreadMutexT* mtx_ptr = &file->_Mutex;
     u8 file_index = file->_Idx;
     u16 file_mode = file->_Mode & 0x80;
 
@@ -115,9 +116,9 @@ OrbisFILE* PS4_SYSV_ABI internal__Foprep(const char* path, const char* mode, Orb
         // Closes the file and returns EINVAL.
         file->_Mode = file_mode;
         if (flag == 0) {
-            internal__Mtxinit(&file_mtx, nullptr);
+            internal__Mtxinit(mtx_ptr, nullptr);
         } else {
-            file->_Mutex = file_mtx;
+            file->_Mutex = mtx;
             internal__Unlockfilelock(file);
         }
         internal_fclose(file);
@@ -156,9 +157,9 @@ OrbisFILE* PS4_SYSV_ABI internal__Foprep(const char* path, const char* mode, Orb
     if (fd < 0) {
         // Closes the file, but ensures errno is unchanged.
         if (flag == 0) {
-            internal__Mtxinit(&file_mtx, nullptr);
+            internal__Mtxinit(mtx_ptr, nullptr);
         } else {
-            file->_Mutex = file_mtx;
+            file->_Mutex = mtx;
             internal__Unlockfilelock(file);
         }
         s32 old_errno = *Kernel::__Error();
@@ -170,9 +171,9 @@ OrbisFILE* PS4_SYSV_ABI internal__Foprep(const char* path, const char* mode, Orb
     if (flag == 0) {
         char mtx_name[0x20];
         std::snprintf(mtx_name, 0x20, "FileFD:0x%08X", fd);
-        internal__Mtxinit(&file_mtx, mtx_name);
+        internal__Mtxinit(mtx_ptr, mtx_name);
     } else {
-        file->_Mutex = file_mtx;
+        file->_Mutex = mtx;
     }
     return file;
 }
diff --git a/src/core/libraries/libc_internal/libc_internal_threads.cpp b/src/core/libraries/libc_internal/libc_internal_threads.cpp
index 9a463a1e2..2d8ddaccb 100644
--- a/src/core/libraries/libc_internal/libc_internal_threads.cpp
+++ b/src/core/libraries/libc_internal/libc_internal_threads.cpp
@@ -10,8 +10,9 @@ namespace Libraries::LibcInternal {
 void getMutexName(char* buf, u64 size, const char* name) {
     if (name != nullptr) {
         std::snprintf(buf, size, "SceLibcI_%s", name);
+    } else {
+        std::snprintf(buf, size, "SceLibcI");
     }
-    std::snprintf(buf, size, "SceLibcI");
 }
 
 s32 PS4_SYSV_ABI internal__Mtxinit(Libraries::Kernel::PthreadMutexT* mtx, const char* name) {
@@ -26,7 +27,7 @@ s32 PS4_SYSV_ABI internal__Mtxinit(Libraries::Kernel::PthreadMutexT* mtx, const
 
     result = Libraries::Kernel::posix_pthread_mutexattr_settype(
         &attr, Libraries::Kernel::PthreadMutexType::Recursive);
-    if (result != 0) {
+    if (result == 0) {
         s32 mtx_init_result = Libraries::Kernel::scePthreadMutexInit(mtx, &attr, mtx_name);
         result = Libraries::Kernel::posix_pthread_mutexattr_destroy(&attr);
         if (mtx_init_result == 0 && result == 0) {