From 6a47669d2182f52019dfa8d8a07595b283f4e4e4 Mon Sep 17 00:00:00 2001
From: twinaphex <autechre1024@hotmail.com>
Date: Tue, 23 Jan 2018 03:41:25 +0100
Subject: [PATCH] Prevent some heap corruptions/exceptions

---
 libretro-common/compat/fopen_utf8.c         | 3 ++-
 libretro-common/formats/png/rpng.c          | 2 +-
 libretro-common/streams/trans_stream_zlib.c | 3 ++-
 menu/drivers/xmb.c                          | 3 ++-
 4 files changed, 7 insertions(+), 4 deletions(-)

diff --git a/libretro-common/compat/fopen_utf8.c b/libretro-common/compat/fopen_utf8.c
index 65fa4c9dc8..abd50cf275 100644
--- a/libretro-common/compat/fopen_utf8.c
+++ b/libretro-common/compat/fopen_utf8.c
@@ -22,7 +22,8 @@ FILE* fopen_utf8(const char * filename, const char * mode)
    if (!filename_local)
       return NULL;
    ret = fopen(filename_local, mode);
-   free(filename_local);
+   if (filename_local)
+      free(filename_local);
    return ret;
 #else
    wchar_t * filename_w = utf8_to_utf16_string_alloc(filename);
diff --git a/libretro-common/formats/png/rpng.c b/libretro-common/formats/png/rpng.c
index c316ea28f0..b9010c1320 100644
--- a/libretro-common/formats/png/rpng.c
+++ b/libretro-common/formats/png/rpng.c
@@ -1220,7 +1220,7 @@ bool rpng_set_buf_ptr(rpng_t *rpng, void *data)
 
 rpng_t *rpng_alloc(void)
 {
-   rpng_t *rpng = (rpng_t*)calloc(1, sizeof(rpng_t));
+   rpng_t *rpng = (rpng_t*)calloc(1, sizeof(*rpng));
    if (!rpng)
       return NULL;
    return rpng;
diff --git a/libretro-common/streams/trans_stream_zlib.c b/libretro-common/streams/trans_stream_zlib.c
index d37e6b9713..ec350119ca 100644
--- a/libretro-common/streams/trans_stream_zlib.c
+++ b/libretro-common/streams/trans_stream_zlib.c
@@ -69,7 +69,8 @@ static void zlib_inflate_stream_free(void *data)
       return;
    if (z->inited)
       inflateEnd(&z->z);
-   free(z);
+   if (z)
+      free(z);
 }
 
 static bool zlib_deflate_define(void *data, const char *prop, uint32_t val)
diff --git a/menu/drivers/xmb.c b/menu/drivers/xmb.c
index 54d8d784b8..03cd69a6f4 100755
--- a/menu/drivers/xmb.c
+++ b/menu/drivers/xmb.c
@@ -3893,7 +3893,8 @@ static void xmb_context_reset(void *data, bool is_threaded)
          xmb_update_thumbnail_image(xmb);
       xmb_update_savestate_thumbnail_image(xmb);
 
-      free(iconpath);
+      if (iconpath)
+         free(iconpath);
    }
 }