diff options
author | Denys Vlasenko | 2015-10-30 23:41:53 +0100 |
---|---|---|
committer | Denys Vlasenko | 2015-10-30 23:41:53 +0100 |
commit | 6bd3fff51aa74e2ee2d87887b12182a3b09792ef (patch) | |
tree | 84b3db20aa35689538306483c0c2be9ec4670253 /archival | |
parent | 95650a86d176ee83a264fd9e7047c414b71ee7cb (diff) | |
download | busybox-6bd3fff51aa74e2ee2d87887b12182a3b09792ef.zip busybox-6bd3fff51aa74e2ee2d87887b12182a3b09792ef.tar.gz |
[g]unzip: fix recent breakage.
Also, do emit error message we so painstakingly pass from gzip internals
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Diffstat (limited to 'archival')
-rw-r--r-- | archival/libarchive/decompress_gunzip.c | 33 |
1 files changed, 21 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; } |