From: Joakim Tjernlund <Joakim.Tjernlund@transmode.se>
Date: Mon, 8 Feb 2010 17:55:15 +0000 (+0100)
Subject: gunzip: inflate_codes(): add fix from upstream gzip to prevent false CRC error
X-Git-Tag: 1_17_0~469
X-Git-Url: https://git.librecmc.org/?a=commitdiff_plain;h=0866b369003fbf81f8f35eb15360a628b3f3aa9a;p=oweals%2Fbusybox.git

gunzip: inflate_codes(): add fix from upstream gzip to prevent false CRC error

Signed-off-by: Joakim Tjernlund <Joakim.Tjernlund@transmode.se>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
---

diff --git a/archival/libunarchive/decompress_unzip.c b/archival/libunarchive/decompress_unzip.c
index feaa047bd..33e877ec8 100644
--- a/archival/libunarchive/decompress_unzip.c
+++ b/archival/libunarchive/decompress_unzip.c
@@ -575,13 +575,16 @@ static NOINLINE int inflate_codes(STATE_PARAM_ONLY)
 			do {
 				/* Was: nn -= (e = (e = GUNZIP_WSIZE - ((dd &= GUNZIP_WSIZE - 1) > w ? dd : w)) > nn ? nn : e); */
 				/* Who wrote THAT?? rewritten as: */
+				unsigned delta;
+
 				dd &= GUNZIP_WSIZE - 1;
 				e = GUNZIP_WSIZE - (dd > w ? dd : w);
+				delta = w > dd ? w - dd : dd - w;
 				if (e > nn) e = nn;
 				nn -= e;
 
 				/* copy to new buffer to prevent possible overwrite */
-				if (w - dd >= e) {	/* (this test assumes unsigned comparison) */
+				if (delta >= e) {
 					memcpy(gunzip_window + w, gunzip_window + dd, e);
 					w += e;
 					dd += e;