tiffcrop: disable incompatibility of -Z, -X, -Y, -z options with any PAGE_MODE_x option (fixes #411 and #413)

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.

1 files changed, 8 insertions, 0 deletions

diff --git a/doc/tools/tiffcrop.rst b/doc/tools/tiffcrop.rst
index ee0d2d81..b5e8e744 100644
--- a/doc/tools/tiffcrop.rst
+++ b/doc/tools/tiffcrop.rst
@@ -415,6 +415,14 @@ Options
   Note: :program:`tiffcrop` may be compiled with :command:`-DDEVELMODE` to enable
   additional very low level debug reporting.
 
+However, not all option combinations are permitted.
+
+  Note 1: The (-X|-Y), -Z, -z and -S options are mutually exclusive.
+  In no case should the options be applied to a given selection successively.
+
+  Note 2: 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.
+  
 Examples
 --------