backport of:

From 4746f16253b784287bc8a5003990c1c3b9a03a62 Mon Sep 17 00:00:00 2001
From: Su_Laus <sulau@freenet.de>
Date: Thu, 25 Aug 2022 16:11:41 +0200
Subject: [PATCH] tiffcrop: disable incompatibility of -Z, -X, -Y, -z options
 with any PAGE_MODE_x option (fixes #411 and #413)
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tiffcrop does not support –Z, -z, -X and –Y options together with any other PAGE_MODE_x options like  -H, -V, -P, -J, -K or –S.

Code analysis:

With the options –Z, -z, the crop.selections are set to a value > 0. Within main(), this triggers the call of processCropSelections(), which copies the sections from the read_buff into seg_buffs[].
In the following code in main(), the only supported step, where that seg_buffs are further handled are within an if-clause with  if (page.mode == PAGE_MODE_NONE) .

Execution of the else-clause often leads to buffer-overflows.

Therefore, the above option combination is not supported and will be disabled to prevent those buffer-overflows.

The MR solves issues #411 and #413.
---
 doc/tools/tiffcrop.rst |  8 ++++++++
 tools/tiffcrop.c       | 32 +++++++++++++++++++++++++-------
 2 files changed, 33 insertions(+), 7 deletions(-)

--- tiff-4.4.0.orig/tools/tiffcrop.c
+++ tiff-4.4.0/tools/tiffcrop.c
@@ -2155,6 +2158,16 @@ void  process_command_opts (int argc, ch
         TIFFError("tiffcrop input error", "The crop options(-X|-Y), -Z, -z and -S are mutually exclusive.->exit");
         exit(EXIT_FAILURE);
     }
+    /* Check for not allowed combination:
+     * Any of the -X, -Y, -Z and -z options together with other PAGE_MODE_x options
+     * such as -H, -V, -P, -J or -K are not supported and may cause buffer overflows.
+.    */
+    if ((XY + Z + R > 0) && page->mode != PAGE_MODE_NONE) {
+        TIFFError("tiffcrop input error",
+            "Any of the crop options -X, -Y, -Z and -z together with other PAGE_MODE_x options such as - H, -V, -P, -J or -K is not supported and may cause buffer overflows..->exit");
+        exit(EXIT_FAILURE);
+    }
+
   }  /* end process_command_opts */
 
 /* Start a new output file if one has not been previously opened or