diff --git a/libtiff/tif_dir.c b/libtiff/tif_dir.c

index 8bf3ea7..f812fa2 100644

--- a/libtiff/tif_dir.c

+++ b/libtiff/tif_dir.c

@@ -160,6 +160,7 @@ _TIFFVSetField(TIFF* tif, uint32 tag, va_list ap)

 	TIFFDirectory* td = &tif->tif_dir;

 	int status = 1;

 	uint32 v32, i, v;

+    double dblval;

 	char* s;

 	const TIFFField *fip = TIFFFindField(tif, tag, TIFF_ANY);

 	uint32 standard_tag = tag;

@@ -283,10 +284,16 @@ _TIFFVSetField(TIFF* tif, uint32 tag, va_list ap)

 			setDoubleArrayOneValue(&td->td_smaxsamplevalue, va_arg(ap, double), td->td_samplesperpixel);

 		break;

 	case TIFFTAG_XRESOLUTION:

-		td->td_xresolution = (float) va_arg(ap, double);

+        dblval = va_arg(ap, double);

+        if( dblval < 0 )

+            goto badvaluedouble;

+		td->td_xresolution = (float) dblval;

 		break;

 	case TIFFTAG_YRESOLUTION:

-		td->td_yresolution = (float) va_arg(ap, double);

+        dblval = va_arg(ap, double);

+        if( dblval < 0 )

+            goto badvaluedouble;

+		td->td_yresolution = (float) dblval;

 		break;

 	case TIFFTAG_PLANARCONFIG:

 		v = (uint16) va_arg(ap, uint16_vap);

@@ -693,6 +700,16 @@ badvalue32:

 		va_end(ap);

         }

 	return (0);

+badvaluedouble:

+        {

+		const TIFFField* fip=TIFFFieldWithTag(tif,tag);

+        TIFFErrorExt(tif->tif_clientdata, module,

+             "%s: Bad value %f for \"%s\" tag",

+             tif->tif_name, dblval,

+		     fip->field_name);

+        va_end(ap);

+        }

+    return (0);

 }

 /*

diff --git a/libtiff/tif_next.c b/libtiff/tif_next.c

index 524e127..81084ff 100644

--- a/libtiff/tif_next.c

+++ b/libtiff/tif_next.c

@@ -102,6 +102,8 @@ NeXTDecode(TIFF* tif, uint8* buf, tmsize_t occ, uint16 s)

 		default: {

 			uint32 npixels = 0, grey;

 			uint32 imagewidth = tif->tif_dir.td_imagewidth;

+            if( isTiled(tif) )

+                imagewidth = tif->tif_dir.td_tilewidth;

 			/*

 			 * The scanline is composed of a sequence of constant

@@ -139,10 +141,28 @@ bad:

 	return (0);

 }

+static int

+NeXTPreDecode(TIFF* tif, uint16 s)

+{

+	static const char module[] = "NeXTPreDecode";

+	TIFFDirectory *td = &tif->tif_dir;

+	(void)s;

+

+	if( td->td_bitspersample != 2 )

+	{

+		TIFFErrorExt(tif->tif_clientdata, module, "Unsupported BitsPerSample = %d",

+					 td->td_bitspersample);

+		return (0);

+	}

+	return (1);

+}

+

+

 int

 TIFFInitNeXT(TIFF* tif, int scheme)

 {

 	(void) scheme;

+	tif->tif_predecode = NeXTPreDecode;

 	tif->tif_decoderow = NeXTDecode;  

 	tif->tif_decodestrip = NeXTDecode;  

 	tif->tif_decodetile = NeXTDecode;

diff --git a/tools/tiff2pdf.c b/tools/tiff2pdf.c

index 26a1acb..2a64ec3 100644

--- a/tools/tiff2pdf.c

+++ b/tools/tiff2pdf.c

@@ -1165,6 +1165,15 @@ void t2p_read_tiff_init(T2P* t2p, TIFF* input){

 		if( (TIFFGetField(input, TIFFTAG_PLANARCONFIG, &xuint16) != 0)

 			&& (xuint16 == PLANARCONFIG_SEPARATE ) ){

 				TIFFGetField(input, TIFFTAG_SAMPLESPERPIXEL, &xuint16);

+                if( (t2p->tiff_tiles[i].tiles_tilecount % xuint16) != 0 )

+                {

+                    TIFFError(

+                        TIFF2PDF_MODULE, 

+                        "Invalid tile count, %s", 

+                        TIFFFileName(input));

+                    t2p->t2p_error = T2P_ERR_ERROR;

+                    return;

+                }

 				t2p->tiff_tiles[i].tiles_tilecount/= xuint16;

 		}

 		if( t2p->tiff_tiles[i].tiles_tilecount > 0){

@@ -1545,6 +1554,22 @@ void t2p_read_tiff_data(T2P* t2p, TIFF* input){

 #endif

 			break;

 		case PHOTOMETRIC_CIELAB:

+            if( t2p->tiff_samplesperpixel != 3){

+                TIFFError(

+                    TIFF2PDF_MODULE, 

+                    "Unsupported samplesperpixel = %d for CIELAB", 

+                    t2p->tiff_samplesperpixel);

+                t2p->t2p_error = T2P_ERR_ERROR;

+                return;

+            }

+            if( t2p->tiff_bitspersample != 8){

+                TIFFError(

+                    TIFF2PDF_MODULE, 

+                    "Invalid bitspersample = %d for CIELAB", 

+                    t2p->tiff_bitspersample);

+                t2p->t2p_error = T2P_ERR_ERROR;

+                return;

+            }

 			t2p->pdf_labrange[0]= -127;

 			t2p->pdf_labrange[1]= 127;

 			t2p->pdf_labrange[2]= -127;

@@ -1560,6 +1585,22 @@ void t2p_read_tiff_data(T2P* t2p, TIFF* input){

 			t2p->pdf_colorspace=T2P_CS_LAB;

 			break;

 		case PHOTOMETRIC_ITULAB:

+            if( t2p->tiff_samplesperpixel != 3){

+                TIFFError(

+                    TIFF2PDF_MODULE, 

+                    "Unsupported samplesperpixel = %d for ITULAB", 

+                    t2p->tiff_samplesperpixel);

+                t2p->t2p_error = T2P_ERR_ERROR;

+                return;

+            }

+            if( t2p->tiff_bitspersample != 8){

+                TIFFError(

+                    TIFF2PDF_MODULE, 

+                    "Invalid bitspersample = %d for ITULAB", 

+                    t2p->tiff_bitspersample);

+                t2p->t2p_error = T2P_ERR_ERROR;

+                return;

+            }

 			t2p->pdf_labrange[0]=-85;

 			t2p->pdf_labrange[1]=85;

 			t2p->pdf_labrange[2]=-75;

diff --git a/tools/tiffcrop.c b/tools/tiffcrop.c

index abeb4f6..ea4f7a1 100644

--- a/tools/tiffcrop.c

+++ b/tools/tiffcrop.c

@@ -1205,9 +1205,10 @@ static int writeBufferToContigTiles (TIFF* out, uint8* buf, uint32 imagelength,

   tsize_t tilesize = TIFFTileSize(out);

   unsigned char *tilebuf = NULL;

-  TIFFGetField(out, TIFFTAG_TILELENGTH, &tl;;

-  TIFFGetField(out, TIFFTAG_TILEWIDTH, &tw);

-  TIFFGetField(out, TIFFTAG_BITSPERSAMPLE, &bps;;

+  if( !TIFFGetField(out, TIFFTAG_TILELENGTH, &tl) ||

+      !TIFFGetField(out, TIFFTAG_TILEWIDTH, &tw) ||

+      !TIFFGetField(out, TIFFTAG_BITSPERSAMPLE, &bps) )

+      return 1;

   tile_buffsize = tilesize;

   if (tilesize < (tsize_t)(tl * tile_rowsize))