1From 895867b72bd6c46da79de1a07d0993cd104e92cd Mon Sep 17 00:00:00 2001
2From: Even Rouault <even.rouault@spatialys.com>
3Date: Sun, 6 Feb 2022 13:08:38 +0100
4Subject: [PATCH] TIFFFetchStripThing(): avoid calling memcpy() with a null
5 source pointer and size of zero (fixes #362)
6
7Upstream-Status: Backport
8CVE: CVE-2022-0561
9
10---
11 libtiff/tif_dirread.c | 5 +++--
12 1 file changed, 3 insertions(+), 2 deletions(-)
13
14diff --git a/libtiff/tif_dirread.c b/libtiff/tif_dirread.c
15index ae52ad4..d654a1c 100644
16--- a/libtiff/tif_dirread.c
17+++ b/libtiff/tif_dirread.c
18@@ -5766,8 +5766,9 @@ TIFFFetchStripThing(TIFF* tif, TIFFDirEntry* dir, uint32_t nstrips, uint64_t** l
19 			_TIFFfree(data);
20 			return(0);
21 		}
22-                _TIFFmemcpy(resizeddata,data, (uint32_t)dir->tdir_count * sizeof(uint64_t));
23-                _TIFFmemset(resizeddata+(uint32_t)dir->tdir_count, 0, (nstrips - (uint32_t)dir->tdir_count) * sizeof(uint64_t));
24+		if( dir->tdir_count )
25+			_TIFFmemcpy(resizeddata,data, (uint32_t)dir->tdir_count * sizeof(uint64_t));
26+		_TIFFmemset(resizeddata+(uint32_t)dir->tdir_count, 0, (nstrips - (uint32_t)dir->tdir_count) * sizeof(uint64_t));
27 		_TIFFfree(data);
28 		data=resizeddata;
29 	}
30