From 6bd3fff51aa74e2ee2d87887b12182a3b09792ef Mon Sep 17 00:00:00 2001 From: Denys Vlasenko Date: Fri, 30 Oct 2015 23:41:53 +0100 Subject: [PATCH] [g]unzip: fix recent breakage. Also, do emit error message we so painstakingly pass from gzip internals Signed-off-by: Denys Vlasenko Signed-off-by: Arnout Vandecappelle (Essensium/Mind) --- archival/libarchive/decompress_gunzip.c | 33 +++++++++++++++++++++------------ testsuite/unzip.tests | 1 + 2 files changed, 22 insertions(+), 12 deletions(-) diff --git a/archival/libarchive/decompress_gunzip.c b/archival/libarchive/decompress_gunzip.c index 30bf451..20e4d9a 100644 --- a/archival/libarchive/decompress_gunzip.c +++ b/archival/libarchive/decompress_gunzip.c @@ -309,8 +309,7 @@ static int huft_build(const unsigned *b, const unsigned n, huft_t *q; /* points to current table */ huft_t r; /* table entry for structure assignment */ huft_t *u[BMAX]; /* table stack */ - unsigned v[N_MAX]; /* values in order of bit length */ - unsigned v_end; + unsigned v[N_MAX + 1]; /* values in order of bit length. last v[] is never used */ int ws[BMAX + 1]; /* bits decoded stack */ int w; /* bits decoded */ unsigned x[BMAX + 1]; /* bit offsets, then code stack */ @@ -365,15 +364,17 @@ static int huft_build(const unsigned *b, const unsigned n, *xp++ = j; } - /* Make a table of values in order of bit lengths */ + /* Make a table of values in order of bit lengths. + * To detect bad input, unused v[i]'s are set to invalid value UINT_MAX. + * In particular, last v[i] is never filled and must not be accessed. + */ + memset(v, 0xff, sizeof(v)); p = b; i = 0; - v_end = 0; do { j = *p++; if (j != 0) { v[x[j]++] = i; - v_end = x[j]; } } while (++i < n); @@ -435,7 +436,9 @@ static int huft_build(const unsigned *b, const unsigned n, /* set up table entry in r */ r.b = (unsigned char) (k - w); - if (p >= v + v_end) { // Was "if (p >= v + n)" but v[] can be shorter! + if (/*p >= v + n || -- redundant, caught by the second check: */ + *p == UINT_MAX /* do we access uninited v[i]? (see memset(v))*/ + ) { r.e = 99; /* out of values--invalid code */ } else if (*p < s) { r.e = (unsigned char) (*p < 256 ? 16 : 15); /* 256 is EOB code */ @@ -520,8 +523,9 @@ static NOINLINE int inflate_codes(STATE_PARAM_ONLY) e = t->e; if (e > 16) do { - if (e == 99) - abort_unzip(PASS_STATE_ONLY);; + if (e == 99) { + abort_unzip(PASS_STATE_ONLY); + } bb >>= t->b; k -= t->b; e -= 16; @@ -557,8 +561,9 @@ static NOINLINE int inflate_codes(STATE_PARAM_ONLY) e = t->e; if (e > 16) do { - if (e == 99) + if (e == 99) { abort_unzip(PASS_STATE_ONLY); + } bb >>= t->b; k -= t->b; e -= 16; @@ -824,8 +829,9 @@ static int inflate_block(STATE_PARAM smallint *e) b_dynamic >>= 4; k_dynamic -= 4; - if (nl > 286 || nd > 30) + if (nl > 286 || nd > 30) { abort_unzip(PASS_STATE_ONLY); /* bad lengths */ + } /* read in bit-length-code lengths */ for (j = 0; j < nb; j++) { @@ -906,12 +912,14 @@ static int inflate_block(STATE_PARAM smallint *e) bl = lbits; i = huft_build(ll, nl, 257, cplens, cplext, &inflate_codes_tl, &bl); - if (i != 0) + if (i != 0) { abort_unzip(PASS_STATE_ONLY); + } bd = dbits; i = huft_build(ll + nl, nd, 0, cpdist, cpdext, &inflate_codes_td, &bd); - if (i != 0) + if (i != 0) { abort_unzip(PASS_STATE_ONLY); + } /* set up data for inflate_codes() */ inflate_codes_setup(PASS_STATE bl, bd); @@ -999,6 +1007,7 @@ inflate_unzip_internal(STATE_PARAM transformer_state_t *xstate) error_msg = "corrupted data"; if (setjmp(error_jmp)) { /* Error from deep inside zip machinery */ + bb_error_msg(error_msg); n = -1; goto ret; } diff --git a/testsuite/unzip.tests b/testsuite/unzip.tests index ca0a458..d8738a3 100755 --- a/testsuite/unzip.tests +++ b/testsuite/unzip.tests @@ -34,6 +34,7 @@ rm foo.zip testing "unzip (bad archive)" "uudecode; unzip bad.zip 2>&1; echo \$?" \ "Archive: bad.zip inflating: ]3j½r«IK-%Ix +unzip: corrupted data unzip: inflate error 1 " \ -- 2.6.2