libtiff: fix the FPE in tiffcrop (#393) (e4894)

https://github.com/libsdl-org/libtiff/commit/e48949887edfab2cc1b11f5e1cae2e62f1be11fe

From e48949887edfab2cc1b11f5e1cae2e62f1be11fe Mon Sep 17 00:00:00 2001
From: 4ugustus <[EMAIL REDACTED]>
Date: Tue, 8 Mar 2022 16:22:04 +0000
Subject: [PATCH] fix the FPE in tiffcrop (#393)

Backported from commit 32ea0722ee68f503b7a3f9b2d557acb293fc8cde
---
 libtiff/tif_dir.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/libtiff/tif_dir.c b/libtiff/tif_dir.c
index 347b7115..f0295422 100644
--- a/libtiff/tif_dir.c
+++ b/libtiff/tif_dir.c
@@ -335,13 +335,13 @@ _TIFFVSetField(TIFF* tif, uint32 tag, va_list ap)
 		break;
 	case TIFFTAG_XRESOLUTION:
         dblval = va_arg(ap, double);
-        if( dblval < 0 )
+        if( dblval != dblval || dblval < 0 )
             goto badvaluedouble;
 		td->td_xresolution = _TIFFClampDoubleToFloat( dblval );
 		break;
 	case TIFFTAG_YRESOLUTION:
         dblval = va_arg(ap, double);
-        if( dblval < 0 )
+        if( dblval != dblval || dblval < 0 )
             goto badvaluedouble;
 		td->td_yresolution = _TIFFClampDoubleToFloat( dblval );
 		break;