diff --git a/ChangeLog b/ChangeLog
index 0f154d66..93c01f80 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,13 @@
+2016-12-03 Even Rouault <even.rouault at spatialys.com>
+
+	* libtiff/tif_pixarlog.c, libtiff/tif_luv.c: fix heap-based buffer
+	overflow on generation of PixarLog / LUV compressed files, with
+	ColorMap, TransferFunction attached and nasty plays with bitspersample.
+	The fix for LUV has not been tested, but suffers from the same kind
+	of issue of PixarLog.
+	Reported by Agostino Sarubbo.
+	Fixes http://bugzilla.maptools.org/show_bug.cgi?id=2604
+
 2016-12-02 Even Rouault <even.rouault at spatialys.com>
 
 	* tools/tiffcp.c: avoid uint32 underflow in cpDecodedStrips that 
diff --git a/libtiff/tif_luv.c b/libtiff/tif_luv.c
index ca08f30a..f42ac013 100644
--- a/libtiff/tif_luv.c
+++ b/libtiff/tif_luv.c
@@ -1,4 +1,4 @@
-/* $Id: tif_luv.c,v 1.43 2016-09-04 21:32:56 erouault Exp $ */
+/* $Id: tif_luv.c,v 1.44 2016-12-02 23:05:51 erouault Exp $ */
 
 /*
  * Copyright (c) 1997 Greg Ward Larson
@@ -158,6 +158,7 @@
 typedef struct logLuvState LogLuvState;
 
 struct logLuvState {
+        int                     encoder_state;  /* 1 if encoder correctly initialized */
 	int                     user_datafmt;   /* user data format */
 	int                     encode_meth;    /* encoding method */
 	int                     pixel_size;     /* bytes per pixel */
@@ -1552,6 +1553,7 @@ LogLuvSetupEncode(TIFF* tif)
 		    td->td_photometric, "must be either LogLUV or LogL");
 		break;
 	}
+	sp->encoder_state = 1;
 	return (1);
 notsupported:
 	TIFFErrorExt(tif->tif_clientdata, module,
@@ -1563,19 +1565,27 @@ notsupported:
 static void
 LogLuvClose(TIFF* tif)
 {
+        LogLuvState* sp = (LogLuvState*) tif->tif_data;
 	TIFFDirectory *td = &tif->tif_dir;
 
+	assert(sp != 0);
 	/*
 	 * For consistency, we always want to write out the same
 	 * bitspersample and sampleformat for our TIFF file,
 	 * regardless of the data format being used by the application.
 	 * Since this routine is called after tags have been set but
 	 * before they have been recorded in the file, we reset them here.
+         * Note: this is really a nasty approach. See PixarLogClose
 	 */
-	td->td_samplesperpixel =
-	    (td->td_photometric == PHOTOMETRIC_LOGL) ? 1 : 3;
-	td->td_bitspersample = 16;
-	td->td_sampleformat = SAMPLEFORMAT_INT;
+        if( sp->encoder_state )
+        {
+            /* See PixarLogClose. Might avoid issues with tags whose size depends
+             * on those below, but not completely sure this is enough. */
+            td->td_samplesperpixel =
+                (td->td_photometric == PHOTOMETRIC_LOGL) ? 1 : 3;
+            td->td_bitspersample = 16;
+            td->td_sampleformat = SAMPLEFORMAT_INT;
+        }
 }
 
 static void
diff --git a/libtiff/tif_pixarlog.c b/libtiff/tif_pixarlog.c
index f4af2bab..9836dce6 100644
--- a/libtiff/tif_pixarlog.c
+++ b/libtiff/tif_pixarlog.c
@@ -1,4 +1,4 @@
-/* $Id: tif_pixarlog.c,v 1.48 2016-09-23 22:12:18 erouault Exp $ */
+/* $Id: tif_pixarlog.c,v 1.49 2016-12-02 23:05:51 erouault Exp $ */
 
 /*
  * Copyright (c) 1996-1997 Sam Leffler
@@ -1233,8 +1233,10 @@ PixarLogPostEncode(TIFF* tif)
 static void
 PixarLogClose(TIFF* tif)
 {
+        PixarLogState* sp = (PixarLogState*) tif->tif_data;
 	TIFFDirectory *td = &tif->tif_dir;
 
+	assert(sp != 0);
 	/* In a really sneaky (and really incorrect, and untruthful, and
 	 * troublesome, and error-prone) maneuver that completely goes against
 	 * the spirit of TIFF, and breaks TIFF, on close, we covertly
@@ -1243,8 +1245,19 @@ PixarLogClose(TIFF* tif)
 	 * readers that don't know about PixarLog, or how to set
 	 * the PIXARLOGDATFMT pseudo-tag.
 	 */
-	td->td_bitspersample = 8;
-	td->td_sampleformat = SAMPLEFORMAT_UINT;
+
+        if (sp->state&PLSTATE_INIT) {
+            /* We test the state to avoid an issue such as in
+             * http://bugzilla.maptools.org/show_bug.cgi?id=2604
+             * What appends in that case is that the bitspersample is 1 and
+             * a TransferFunction is set. The size of the TransferFunction
+             * depends on 1<<bitspersample. So if we increase it, an access
+             * out of the buffer will happen at directory flushing.
+             * Another option would be to clear those targs. 
+             */
+            td->td_bitspersample = 8;
+            td->td_sampleformat = SAMPLEFORMAT_UINT;
+        }
 }
 
 static void