From: Martin Matuska <martin@matuska.org>
Date: Tue, 14 Jan 2020 15:35:31 +0000 (+0100)
Subject: archive_ppmd7.c: avoid possible integer overflow (security)
X-Git-Tag: v3.4.2~41
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=d5475620534c70cb5b9fc78b97d6206625ca9dc3;p=thirdparty%2Flibarchive.git

archive_ppmd7.c: avoid possible integer overflow (security)

Found by LGTM.com code analysis
---

diff --git a/libarchive/archive_ppmd7.c b/libarchive/archive_ppmd7.c
index d0bacc68c..4029395b4 100644
--- a/libarchive/archive_ppmd7.c
+++ b/libarchive/archive_ppmd7.c
@@ -1000,7 +1000,7 @@ static void RangeEnc_ShiftLow(CPpmd7z_RangeEnc *p)
 
 static void RangeEnc_Encode(CPpmd7z_RangeEnc *p, UInt32 start, UInt32 size, UInt32 total)
 {
-  p->Low += start * (p->Range /= total);
+  p->Low += (UInt64)start * (UInt64)(p->Range /= total);
   p->Range *= size;
   while (p->Range < kTopValue)
   {