1From 7b91458541769f3d7eddc55a39d01730af2489fc Mon Sep 17 00:00:00 2001
2From: Even Rouault <even.rouault@spatialys.com>
3Date: Sat, 5 Feb 2022 20:36:41 +0100
4Subject: [PATCH] TIFFReadDirectory(): avoid calling memcpy() with a null
5 source pointer and size of zero (fixes #362)
6
7Upstream-Status: Backport
8CVE: CVE-2022-0562
9
10---
11 libtiff/tif_dirread.c | 3 ++-
12 1 file changed, 2 insertions(+), 1 deletion(-)
13
14diff --git a/libtiff/tif_dirread.c b/libtiff/tif_dirread.c
15index d84147a..ae52ad4 100644
16--- a/libtiff/tif_dirread.c
17+++ b/libtiff/tif_dirread.c
18@@ -4173,7 +4173,8 @@ TIFFReadDirectory(TIFF* tif)
19                     goto bad;
20                 }
21
22-                memcpy(new_sampleinfo, tif->tif_dir.td_sampleinfo, old_extrasamples * sizeof(uint16_t));
23+                if (old_extrasamples > 0)
24+                    memcpy(new_sampleinfo, tif->tif_dir.td_sampleinfo, old_extrasamples * sizeof(uint16_t));
25                 _TIFFsetShortArray(&tif->tif_dir.td_sampleinfo, new_sampleinfo, tif->tif_dir.td_extrasamples);
26                 _TIFFfree(new_sampleinfo);
27         }
28