libtiff: Merge branch 'TiffClose_NULL_ptr_dereferencing_fix_515' into 'master' (f171d)

SDL Commits
1 
From d63de61b1ec3385f6383ef9a1f453e4b8b11d536 Mon Sep 17 00:00:00 2001
From: Su_Laus <[EMAIL REDACTED]>
Date: Fri, 3 Feb 2023 17:38:55 +0100
Subject: [PATCH] TIFFClose() avoid NULL pointer dereferencing. fix#515

Closes #515
---
 libtiff/tif_close.c | 11 +++++++----
 tools/tiffcrop.c    |  5 ++++-
 2 files changed, 11 insertions(+), 5 deletions(-)

diff --git a/libtiff/tif_close.c b/libtiff/tif_close.c
index 985d290c..907d7f13 100644
--- a/libtiff/tif_close.c
+++ b/libtiff/tif_close.c
@@ -147,9 +147,12 @@ void _TIFFCleanupIFDOffsetAndNumberMaps(TIFF *tif)
 
 void TIFFClose(TIFF *tif)
 {
-    TIFFCloseProc closeproc = tif->tif_closeproc;
-    thandle_t fd = tif->tif_clientdata;
+    if (tif != NULL)
+    {
+        TIFFCloseProc closeproc = tif->tif_closeproc;
+        thandle_t fd = tif->tif_clientdata;
 
-    TIFFCleanup(tif);
-    (void)(*closeproc)(fd);
+        TIFFCleanup(tif);
+        (void)(*closeproc)(fd);
+    }
 }
diff --git a/tools/tiffcrop.c b/tools/tiffcrop.c
index 7db69883..84e26ac6 100644
--- a/tools/tiffcrop.c
+++ b/tools/tiffcrop.c
@@ -2920,7 +2920,10 @@ int main(int argc, char *argv[])
         }
     }
 
-    TIFFClose(out);
+    if (out != NULL)
+    {
+        TIFFClose(out);
+    }
 
     return (0);
 } /* end main */