* libtiff/tif_dir.c: discard values of SMinSampleValue and

SMaxSampleValue when they have been read and the value of
SamplesPerPixel is changed afterwards (like when reading a
OJPEG compressed image with a missing SamplesPerPixel tag,
and whose photometric is RGB or YCbCr, forcing SamplesPerPixel
being 3). Otherwise when rewriting the directory (for example
with tiffset, we will expect 3 values whereas the array had been
allocated with just one), thus causing a out of bound read access.
Fixes http://bugzilla.maptools.org/show_bug.cgi?id=2500
(CVE-2014-8127, duplicate: CVE-2016-3658)

* libtiff/tif_write.c: avoid null pointer dereference on td_stripoffset
when writing directory, if FIELD_STRIPOFFSETS was artificially set
for a hack case	in OJPEG case.
Fixes http://bugzilla.maptools.org/show_bug.cgi?id=2500
(CVE-2014-8127, duplicate: CVE-2016-3658)

3 files changed, 57 insertions, 4 deletions

diff --git a/ChangeLog b/ChangeLog
index ae09b648..29941fc3 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,24 @@
 2016-10-25 Even Rouault <even.rouault at spatialys.com>
 
+	* libtiff/tif_dir.c: discard values of SMinSampleValue and
+	SMaxSampleValue when they have been read and the value of
+	SamplesPerPixel is changed afterwards (like when reading a
+	OJPEG compressed image with a missing SamplesPerPixel tag,
+	and whose photometric is RGB or YCbCr, forcing SamplesPerPixel
+	being 3). Otherwise when rewriting the directory (for example
+	with tiffset, we will expect 3 values whereas the array had been
+	allocated with just one), thus causing a out of bound read access.
+	Fixes http://bugzilla.maptools.org/show_bug.cgi?id=2500
+	(CVE-2014-8127, duplicate: CVE-2016-3658)
+	
+	* libtiff/tif_write.c: avoid null pointer dereference on td_stripoffset
+	when writing directory, if FIELD_STRIPOFFSETS was artificially set
+	for a hack case	in OJPEG case.
+	Fixes http://bugzilla.maptools.org/show_bug.cgi?id=2500
+	(CVE-2014-8127, duplicate: CVE-2016-3658)
+
+2016-10-25 Even Rouault <even.rouault at spatialys.com>
+
 	* tools/tiffinfo.c: fix out-of-bound read on some tiled images.
 	(http://bugzilla.maptools.org/show_bug.cgi?id=2517)
 
diff --git a/libtiff/tif_dir.c b/libtiff/tif_dir.c
index ca5d979f..ad21655a 100644
--- a/libtiff/tif_dir.c
+++ b/libtiff/tif_dir.c
@@ -1,4 +1,4 @@
-/* $Id: tif_dir.c,v 1.126 2016-09-04 21:32:56 erouault Exp $ */
+/* $Id: tif_dir.c,v 1.127 2016-10-25 21:35:15 erouault Exp $ */
 
 /*
  * Copyright (c) 1988-1997 Sam Leffler
@@ -256,6 +256,28 @@ _TIFFVSetField(TIFF* tif, uint32 tag, va_list ap)
 		v = (uint16) va_arg(ap, uint16_vap);
 		if (v == 0)
 			goto badvalue;
+        if( v != td->td_samplesperpixel )
+        {
+            /* See http://bugzilla.maptools.org/show_bug.cgi?id=2500 */
+            if( td->td_sminsamplevalue != NULL )
+            {
+                TIFFWarningExt(tif->tif_clientdata,module,
+                    "SamplesPerPixel tag value is changing, "
+                    "but SMinSampleValue tag was read with a different value. Cancelling it");
+                TIFFClrFieldBit(tif,FIELD_SMINSAMPLEVALUE);
+                _TIFFfree(td->td_sminsamplevalue);
+                td->td_sminsamplevalue = NULL;
+            }
+            if( td->td_smaxsamplevalue != NULL )
+            {
+                TIFFWarningExt(tif->tif_clientdata,module,
+                    "SamplesPerPixel tag value is changing, "
+                    "but SMaxSampleValue tag was read with a different value. Cancelling it");
+                TIFFClrFieldBit(tif,FIELD_SMAXSAMPLEVALUE);
+                _TIFFfree(td->td_smaxsamplevalue);
+                td->td_smaxsamplevalue = NULL;
+            }
+        }
 		td->td_samplesperpixel = (uint16) v;
 		break;
 	case TIFFTAG_ROWSPERSTRIP:
diff --git a/libtiff/tif_dirwrite.c b/libtiff/tif_dirwrite.c
index 837fdd0f..d34f6f61 100644
--- a/libtiff/tif_dirwrite.c
+++ b/libtiff/tif_dirwrite.c
@@ -1,4 +1,4 @@
-/* $Id: tif_dirwrite.c,v 1.82 2016-09-02 22:42:00 erouault Exp $ */
+/* $Id: tif_dirwrite.c,v 1.83 2016-10-25 21:35:15 erouault Exp $ */
 
 /*
  * Copyright (c) 1988-1997 Sam Leffler
@@ -542,8 +542,20 @@ TIFFWriteDirectorySec(TIFF* tif, int isimage, int imagedone, uint64* pdiroff)
 			{
 				if (!isTiled(tif))
 				{
-					if (!TIFFWriteDirectoryTagLongLong8Array(tif,&ndir,dir,TIFFTAG_STRIPOFFSETS,tif->tif_dir.td_nstrips,tif->tif_dir.td_stripoffset))
-						goto bad;
+                    /* td_stripoffset might be NULL in an odd OJPEG case. See
+                     *  tif_dirread.c around line 3634.
+                     * XXX: OJPEG hack.
+                     * If a) compression is OJPEG, b) it's not a tiled TIFF,
+                     * and c) the number of strips is 1,
+                     * then we tolerate the absence of stripoffsets tag,
+                     * because, presumably, all required data is in the
+                     * JpegInterchangeFormat stream.
+                     * We can get here when using tiffset on such a file.
+                     * See http://bugzilla.maptools.org/show_bug.cgi?id=2500
+                    */
+                    if (tif->tif_dir.td_stripoffset != NULL &&
+                        !TIFFWriteDirectoryTagLongLong8Array(tif,&ndir,dir,TIFFTAG_STRIPOFFSETS,tif->tif_dir.td_nstrips,tif->tif_dir.td_stripoffset))
+                        goto bad;
 				}
 				else
 				{