From: sms Subject: Fix CVE-2014-8139: CRC32 verification heap-based overflow Bug-Debian: http://bugs.debian.org/773722 The patch comes from unzip_6.0-8+deb7u2.debian.tar.gz Upstream-Status: Backport CVE: CVE-2014-8139 Signed-off-by: Roy Li --- a/extract.c +++ b/extract.c @@ -298,6 +298,8 @@ #ifndef SFX static ZCONST char Far InconsistEFlength[] = "bad extra-field entry:\n \ EF block length (%u bytes) exceeds remaining EF data (%u bytes)\n"; + static ZCONST char Far TooSmallEBlength[] = "bad extra-field entry:\n \ + EF block length (%u bytes) invalid (< %d)\n"; static ZCONST char Far InvalidComprDataEAs[] = " invalid compressed data for EAs\n"; # if (defined(WIN32) && defined(NTSD_EAS)) @@ -2023,7 +2025,8 @@ ebID = makeword(ef); ebLen = (unsigned)makeword(ef+EB_LEN); - if (ebLen > (ef_len - EB_HEADSIZE)) { + if (ebLen > (ef_len - EB_HEADSIZE)) + { /* Discovered some extra field inconsistency! */ if (uO.qflag) Info(slide, 1, ((char *)slide, "%-22s ", @@ -2158,11 +2161,19 @@ } break; case EF_PKVMS: - if (makelong(ef+EB_HEADSIZE) != + if (ebLen < 4) + { + Info(slide, 1, + ((char *)slide, LoadFarString(TooSmallEBlength), + ebLen, 4)); + } + else if (makelong(ef+EB_HEADSIZE) != crc32(CRCVAL_INITIAL, ef+(EB_HEADSIZE+4), (extent)(ebLen-4))) + { Info(slide, 1, ((char *)slide, LoadFarString(BadCRC_EAs))); + } break; case EF_PKW32: case EF_PKUNIX: