libtiff: tiffset: fix global-buffer-overflow for ASCII tags where count is required (fixes #355) (6ac63)

SDL Commits
1 
From 6ac631c1b490e9c736ab4019aeadebdfa4cae011 Mon Sep 17 00:00:00 2001
From: 4ugustus <[EMAIL REDACTED]>
Date: Tue, 25 Jan 2022 16:25:28 +0000
Subject: [PATCH] tiffset: fix global-buffer-overflow for ASCII tags where
 count is required (fixes #355)

---
 tools/tiffset.c | 17 ++++++++++++++---
 1 file changed, 14 insertions(+), 3 deletions(-)

diff --git a/tools/tiffset.c b/tools/tiffset.c
index 75cf45c0..1330d828 100644
--- a/tools/tiffset.c
+++ b/tools/tiffset.c
@@ -32,6 +32,7 @@
 #include <stdio.h>
 #include <string.h>
 #include <stdlib.h>
+#include <stdint.h>
 
 #include "tiffio.h"
 
@@ -148,9 +149,19 @@ main(int argc, char* argv[])
 
             arg_index++;
             if (TIFFFieldDataType(fip) == TIFF_ASCII) {
-                if (TIFFSetField(tiff, TIFFFieldTag(fip), argv[arg_index]) != 1)
-                    fprintf( stderr, "Failed to set %s=%s\n",
-                             TIFFFieldName(fip), argv[arg_index] );
+                if(TIFFFieldPassCount( fip )) {
+                    size_t len;
+                    len = strlen(argv[arg_index]) + 1;
+                    if (len > UINT16_MAX || TIFFSetField(tiff, TIFFFieldTag(fip),
+                            (uint16)len, argv[arg_index]) != 1)
+                        fprintf( stderr, "Failed to set %s=%s\n",
+                            TIFFFieldName(fip), argv[arg_index] );
+                } else {
+                    if (TIFFSetField(tiff, TIFFFieldTag(fip),
+                            argv[arg_index]) != 1)
+                        fprintf( stderr, "Failed to set %s=%s\n",
+                            TIFFFieldName(fip), argv[arg_index] );
+                }
             } else if (TIFFFieldWriteCount(fip) > 0
 		       || TIFFFieldWriteCount(fip) == TIFF_VARIABLE) {
                 int     ret = 1;