From mboxrd@z Thu Jan 1 00:00:00 1970 From: Peter =?utf-8?q?M=C3=BCller?= To: development@lists.ipfire.org Subject: [PATCH] zlib: Pick up upstream patch for memory corruption fix Date: Thu, 24 Mar 2022 08:37:22 +0000 Message-ID: MIME-Version: 1.0 Content-Type: multipart/mixed; boundary="===============1850201643795595007==" List-Id: --===============1850201643795595007== Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable See: https://www.openwall.com/lists/oss-security/2022/03/24/1 Signed-off-by: Peter M=C3=BCller --- lfs/zlib | 6 +- ...ate-on-some-input-when-using-Z_FIXED.patch | 338 ++++++++++++++++++ 2 files changed, 343 insertions(+), 1 deletion(-) create mode 100644 src/patches/zlib-fix-a-bug-that-can-crash-deflate-on-some= -input-when-using-Z_FIXED.patch diff --git a/lfs/zlib b/lfs/zlib index 2c89b4803..c2386778d 100644 --- a/lfs/zlib +++ b/lfs/zlib @@ -1,7 +1,7 @@ ############################################################################= ### # = # # IPFire.org - A linux based firewall = # -# Copyright (C) 2007-2021 IPFire Team = # +# Copyright (C) 2007-2022 IPFire Team = # # = # # This program is free software: you can redistribute it and/or modify = # # it under the terms of the GNU General Public License as published by = # @@ -78,6 +78,10 @@ $(TARGET) : $(patsubst %,$(DIR_DL)/%,$(objects)) @$(PREBUILD) @rm -rf $(DIR_APP) && cd $(DIR_SRC) && tar axf $(DIR_DL)/$(DL_FILE) cd $(DIR_APP) && CROSS_PREFIX=3D$(CROSS_PREFIX) ./configure --prefix=3D$(PR= EFIX) --shared + + # https://www.openwall.com/lists/oss-security/2022/03/24/1 + cd $(DIR_APP) && patch -Np1 -i $(DIR_SRC)/src/patches/zlib-fix-a-bug-that-c= an-crash-deflate-on-some-input-when-using-Z_FIXED.patch + cd $(DIR_APP) && make $(MAKETUNING) cd $(DIR_APP) && make install =20 diff --git a/src/patches/zlib-fix-a-bug-that-can-crash-deflate-on-some-input-= when-using-Z_FIXED.patch b/src/patches/zlib-fix-a-bug-that-can-crash-deflate-= on-some-input-when-using-Z_FIXED.patch new file mode 100644 index 000000000..2b46bcce5 --- /dev/null +++ b/src/patches/zlib-fix-a-bug-that-can-crash-deflate-on-some-input-when-us= ing-Z_FIXED.patch @@ -0,0 +1,338 @@ +commit 5c44459c3b28a9bd3283aaceab7c615f8020c531 +Author: Mark Adler +Date: Tue Apr 17 22:09:22 2018 -0700 + + Fix a bug that can crash deflate on some input when using Z_FIXED. + =20 + This bug was reported by Danilo Ramos of Eideticom, Inc. It has + lain in wait 13 years before being found! The bug was introduced + in zlib 1.2.2.2, with the addition of the Z_FIXED option. That + option forces the use of fixed Huffman codes. For rare inputs with + a large number of distant matches, the pending buffer into which + the compressed data is written can overwrite the distance symbol + table which it overlays. That results in corrupted output due to + invalid distances, and can result in out-of-bound accesses, + crashing the application. + =20 + The fix here combines the distance buffer and literal/length + buffers into a single symbol buffer. Now three bytes of pending + buffer space are opened up for each literal or length/distance + pair consumed, instead of the previous two bytes. This assures + that the pending buffer cannot overwrite the symbol table, since + the maximum fixed code compressed length/distance is 31 bits, and + since there are four bytes of pending space for every three bytes + of symbol space. + +diff --git a/deflate.c b/deflate.c +index 425babc..19cba87 100644 +--- a/deflate.c ++++ b/deflate.c +@@ -255,11 +255,6 @@ int ZEXPORT deflateInit2_(strm, level, method, windowBi= ts, memLevel, strategy, + int wrap =3D 1; + static const char my_version[] =3D ZLIB_VERSION; +=20 +- ushf *overlay; +- /* We overlay pending_buf and d_buf+l_buf. This works since the average +- * output size for (length,distance) codes is <=3D 24 bits. +- */ +- + if (version =3D=3D Z_NULL || version[0] !=3D my_version[0] || + stream_size !=3D sizeof(z_stream)) { + return Z_VERSION_ERROR; +@@ -329,9 +324,47 @@ int ZEXPORT deflateInit2_(strm, level, method, windowBi= ts, memLevel, strategy, +=20 + s->lit_bufsize =3D 1 << (memLevel + 6); /* 16K elements by default */ +=20 +- overlay =3D (ushf *) ZALLOC(strm, s->lit_bufsize, sizeof(ush)+2); +- s->pending_buf =3D (uchf *) overlay; +- s->pending_buf_size =3D (ulg)s->lit_bufsize * (sizeof(ush)+2L); ++ /* We overlay pending_buf and sym_buf. This works since the average size ++ * for length/distance pairs over any compressed block is assured to be= 31 ++ * bits or less. ++ * ++ * Analysis: The longest fixed codes are a length code of 8 bits plus 5 ++ * extra bits, for lengths 131 to 257. The longest fixed distance codes= are ++ * 5 bits plus 13 extra bits, for distances 16385 to 32768. The longest ++ * possible fixed-codes length/distance pair is then 31 bits total. ++ * ++ * sym_buf starts one-fourth of the way into pending_buf. So there are ++ * three bytes in sym_buf for every four bytes in pending_buf. Each sym= bol ++ * in sym_buf is three bytes -- two for the distance and one for the ++ * literal/length. As each symbol is consumed, the pointer to the next ++ * sym_buf value to read moves forward three bytes. From that symbol, u= p to ++ * 31 bits are written to pending_buf. The closest the written pending_= buf ++ * bits gets to the next sym_buf symbol to read is just before the last ++ * code is written. At that time, 31*(n-2) bits have been written, just ++ * after 24*(n-2) bits have been consumed from sym_buf. sym_buf starts = at ++ * 8*n bits into pending_buf. (Note that the symbol buffer fills when n= -1 ++ * symbols are written.) The closest the writing gets to what is unread= is ++ * then n+14 bits. Here n is lit_bufsize, which is 16384 by default, and ++ * can range from 128 to 32768. ++ * ++ * Therefore, at a minimum, there are 142 bits of space between what is ++ * written and what is read in the overlain buffers, so the symbols can= not ++ * be overwritten by the compressed data. That space is actually 139 bi= ts, ++ * due to the three-bit fixed-code block header. ++ * ++ * That covers the case where either Z_FIXED is specified, forcing fixed ++ * codes, or when the use of fixed codes is chosen, because that choice ++ * results in a smaller compressed block than dynamic codes. That latter ++ * condition then assures that the above analysis also covers all dynam= ic ++ * blocks. A dynamic-code block will only be chosen to be emitted if it= has ++ * fewer bits than a fixed-code block would for the same set of symbols. ++ * Therefore its average symbol length is assured to be less than 31. So ++ * the compressed data for a dynamic block also cannot overwrite the ++ * symbols from which it is being constructed. ++ */ ++ ++ s->pending_buf =3D (uchf *) ZALLOC(strm, s->lit_bufsize, 4); ++ s->pending_buf_size =3D (ulg)s->lit_bufsize * 4; +=20 + if (s->window =3D=3D Z_NULL || s->prev =3D=3D Z_NULL || s->head =3D=3D = Z_NULL || + s->pending_buf =3D=3D Z_NULL) { +@@ -340,8 +373,12 @@ int ZEXPORT deflateInit2_(strm, level, method, windowBi= ts, memLevel, strategy, + deflateEnd (strm); + return Z_MEM_ERROR; + } +- s->d_buf =3D overlay + s->lit_bufsize/sizeof(ush); +- s->l_buf =3D s->pending_buf + (1+sizeof(ush))*s->lit_bufsize; ++ s->sym_buf =3D s->pending_buf + s->lit_bufsize; ++ s->sym_end =3D (s->lit_bufsize - 1) * 3; ++ /* We avoid equality with lit_bufsize*3 because of wraparound at 64K ++ * on 16 bit machines and because stored blocks are restricted to ++ * 64K-1 bytes. ++ */ +=20 + s->level =3D level; + s->strategy =3D strategy; +@@ -552,7 +589,7 @@ int ZEXPORT deflatePrime (strm, bits, value) +=20 + if (deflateStateCheck(strm)) return Z_STREAM_ERROR; + s =3D strm->state; +- if ((Bytef *)(s->d_buf) < s->pending_out + ((Buf_size + 7) >> 3)) ++ if (s->sym_buf < s->pending_out + ((Buf_size + 7) >> 3)) + return Z_BUF_ERROR; + do { + put =3D Buf_size - s->bi_valid; +@@ -1113,7 +1150,6 @@ int ZEXPORT deflateCopy (dest, source) + #else + deflate_state *ds; + deflate_state *ss; +- ushf *overlay; +=20 +=20 + if (deflateStateCheck(source) || dest =3D=3D Z_NULL) { +@@ -1133,8 +1169,7 @@ int ZEXPORT deflateCopy (dest, source) + ds->window =3D (Bytef *) ZALLOC(dest, ds->w_size, 2*sizeof(Byte)); + ds->prev =3D (Posf *) ZALLOC(dest, ds->w_size, sizeof(Pos)); + ds->head =3D (Posf *) ZALLOC(dest, ds->hash_size, sizeof(Pos)); +- overlay =3D (ushf *) ZALLOC(dest, ds->lit_bufsize, sizeof(ush)+2); +- ds->pending_buf =3D (uchf *) overlay; ++ ds->pending_buf =3D (uchf *) ZALLOC(dest, ds->lit_bufsize, 4); +=20 + if (ds->window =3D=3D Z_NULL || ds->prev =3D=3D Z_NULL || ds->head =3D= =3D Z_NULL || + ds->pending_buf =3D=3D Z_NULL) { +@@ -1148,8 +1183,7 @@ int ZEXPORT deflateCopy (dest, source) + zmemcpy(ds->pending_buf, ss->pending_buf, (uInt)ds->pending_buf_size); +=20 + ds->pending_out =3D ds->pending_buf + (ss->pending_out - ss->pending_bu= f); +- ds->d_buf =3D overlay + ds->lit_bufsize/sizeof(ush); +- ds->l_buf =3D ds->pending_buf + (1+sizeof(ush))*ds->lit_bufsize; ++ ds->sym_buf =3D ds->pending_buf + ds->lit_bufsize; +=20 + ds->l_desc.dyn_tree =3D ds->dyn_ltree; + ds->d_desc.dyn_tree =3D ds->dyn_dtree; +@@ -1925,7 +1959,7 @@ local block_state deflate_fast(s, flush) + FLUSH_BLOCK(s, 1); + return finish_done; + } +- if (s->last_lit) ++ if (s->sym_next) + FLUSH_BLOCK(s, 0); + return block_done; + } +@@ -2056,7 +2090,7 @@ local block_state deflate_slow(s, flush) + FLUSH_BLOCK(s, 1); + return finish_done; + } +- if (s->last_lit) ++ if (s->sym_next) + FLUSH_BLOCK(s, 0); + return block_done; + } +@@ -2131,7 +2165,7 @@ local block_state deflate_rle(s, flush) + FLUSH_BLOCK(s, 1); + return finish_done; + } +- if (s->last_lit) ++ if (s->sym_next) + FLUSH_BLOCK(s, 0); + return block_done; + } +@@ -2170,7 +2204,7 @@ local block_state deflate_huff(s, flush) + FLUSH_BLOCK(s, 1); + return finish_done; + } +- if (s->last_lit) ++ if (s->sym_next) + FLUSH_BLOCK(s, 0); + return block_done; + } +diff --git a/deflate.h b/deflate.h +index 23ecdd3..d4cf1a9 100644 +--- a/deflate.h ++++ b/deflate.h +@@ -217,7 +217,7 @@ typedef struct internal_state { + /* Depth of each subtree used as tie breaker for trees of equal frequen= cy + */ +=20 +- uchf *l_buf; /* buffer for literals or lengths */ ++ uchf *sym_buf; /* buffer for distances and literals/lengths */ +=20 + uInt lit_bufsize; + /* Size of match buffer for literals/lengths. There are 4 reasons for +@@ -239,13 +239,8 @@ typedef struct internal_state { + * - I can't count above 4 + */ +=20 +- uInt last_lit; /* running index in l_buf */ +- +- ushf *d_buf; +- /* Buffer for distances. To simplify the code, d_buf and l_buf have +- * the same number of elements. To use different lengths, an extra flag +- * array would be necessary. +- */ ++ uInt sym_next; /* running index in sym_buf */ ++ uInt sym_end; /* symbol table full when sym_next reaches this */ +=20 + ulg opt_len; /* bit length of current block with optimal trees */ + ulg static_len; /* bit length of current block with static trees */ +@@ -325,20 +320,22 @@ void ZLIB_INTERNAL _tr_stored_block OF((deflate_state = *s, charf *buf, +=20 + # define _tr_tally_lit(s, c, flush) \ + { uch cc =3D (c); \ +- s->d_buf[s->last_lit] =3D 0; \ +- s->l_buf[s->last_lit++] =3D cc; \ ++ s->sym_buf[s->sym_next++] =3D 0; \ ++ s->sym_buf[s->sym_next++] =3D 0; \ ++ s->sym_buf[s->sym_next++] =3D cc; \ + s->dyn_ltree[cc].Freq++; \ +- flush =3D (s->last_lit =3D=3D s->lit_bufsize-1); \ ++ flush =3D (s->sym_next =3D=3D s->sym_end); \ + } + # define _tr_tally_dist(s, distance, length, flush) \ + { uch len =3D (uch)(length); \ + ush dist =3D (ush)(distance); \ +- s->d_buf[s->last_lit] =3D dist; \ +- s->l_buf[s->last_lit++] =3D len; \ ++ s->sym_buf[s->sym_next++] =3D dist; \ ++ s->sym_buf[s->sym_next++] =3D dist >> 8; \ ++ s->sym_buf[s->sym_next++] =3D len; \ + dist--; \ + s->dyn_ltree[_length_code[len]+LITERALS+1].Freq++; \ + s->dyn_dtree[d_code(dist)].Freq++; \ +- flush =3D (s->last_lit =3D=3D s->lit_bufsize-1); \ ++ flush =3D (s->sym_next =3D=3D s->sym_end); \ + } + #else + # define _tr_tally_lit(s, c, flush) flush =3D _tr_tally(s, 0, c) +diff --git a/trees.c b/trees.c +index 4f4a650..decaeb7 100644 +--- a/trees.c ++++ b/trees.c +@@ -416,7 +416,7 @@ local void init_block(s) +=20 + s->dyn_ltree[END_BLOCK].Freq =3D 1; + s->opt_len =3D s->static_len =3D 0L; +- s->last_lit =3D s->matches =3D 0; ++ s->sym_next =3D s->matches =3D 0; + } +=20 + #define SMALLEST 1 +@@ -948,7 +948,7 @@ void ZLIB_INTERNAL _tr_flush_block(s, buf, stored_len, l= ast) +=20 + Tracev((stderr, "\nopt %lu(%lu) stat %lu(%lu) stored %lu lit %u ", + opt_lenb, s->opt_len, static_lenb, s->static_len, stored_le= n, +- s->last_lit)); ++ s->sym_next / 3)); +=20 + if (static_lenb <=3D opt_lenb) opt_lenb =3D static_lenb; +=20 +@@ -1017,8 +1017,9 @@ int ZLIB_INTERNAL _tr_tally (s, dist, lc) + unsigned dist; /* distance of matched string */ + unsigned lc; /* match length-MIN_MATCH or unmatched char (if dist=3D= =3D0) */ + { +- s->d_buf[s->last_lit] =3D (ush)dist; +- s->l_buf[s->last_lit++] =3D (uch)lc; ++ s->sym_buf[s->sym_next++] =3D dist; ++ s->sym_buf[s->sym_next++] =3D dist >> 8; ++ s->sym_buf[s->sym_next++] =3D lc; + if (dist =3D=3D 0) { + /* lc is the unmatched char */ + s->dyn_ltree[lc].Freq++; +@@ -1033,30 +1034,7 @@ int ZLIB_INTERNAL _tr_tally (s, dist, lc) + s->dyn_ltree[_length_code[lc]+LITERALS+1].Freq++; + s->dyn_dtree[d_code(dist)].Freq++; + } +- +-#ifdef TRUNCATE_BLOCK +- /* Try to guess if it is profitable to stop the current block here */ +- if ((s->last_lit & 0x1fff) =3D=3D 0 && s->level > 2) { +- /* Compute an upper bound for the compressed length */ +- ulg out_length =3D (ulg)s->last_lit*8L; +- ulg in_length =3D (ulg)((long)s->strstart - s->block_start); +- int dcode; +- for (dcode =3D 0; dcode < D_CODES; dcode++) { +- out_length +=3D (ulg)s->dyn_dtree[dcode].Freq * +- (5L+extra_dbits[dcode]); +- } +- out_length >>=3D 3; +- Tracev((stderr,"\nlast_lit %u, in %ld, out ~%ld(%ld%%) ", +- s->last_lit, in_length, out_length, +- 100L - out_length*100L/in_length)); +- if (s->matches < s->last_lit/2 && out_length < in_length/2) return = 1; +- } +-#endif +- return (s->last_lit =3D=3D s->lit_bufsize-1); +- /* We avoid equality with lit_bufsize because of wraparound at 64K +- * on 16 bit machines and because stored blocks are restricted to +- * 64K-1 bytes. +- */ ++ return (s->sym_next =3D=3D s->sym_end); + } +=20 + /* =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D +@@ -1069,13 +1047,14 @@ local void compress_block(s, ltree, dtree) + { + unsigned dist; /* distance of matched string */ + int lc; /* match length or unmatched char (if dist =3D=3D 0= ) */ +- unsigned lx =3D 0; /* running index in l_buf */ ++ unsigned sx =3D 0; /* running index in sym_buf */ + unsigned code; /* the code to send */ + int extra; /* number of extra bits to send */ +=20 +- if (s->last_lit !=3D 0) do { +- dist =3D s->d_buf[lx]; +- lc =3D s->l_buf[lx++]; ++ if (s->sym_next !=3D 0) do { ++ dist =3D s->sym_buf[sx++] & 0xff; ++ dist +=3D (unsigned)(s->sym_buf[sx++] & 0xff) << 8; ++ lc =3D s->sym_buf[sx++]; + if (dist =3D=3D 0) { + send_code(s, lc, ltree); /* send a literal byte */ + Tracecv(isgraph(lc), (stderr," '%c' ", lc)); +@@ -1100,11 +1079,10 @@ local void compress_block(s, ltree, dtree) + } + } /* literal or match pair ? */ +=20 +- /* Check that the overlay between pending_buf and d_buf+l_buf is ok= : */ +- Assert((uInt)(s->pending) < s->lit_bufsize + 2*lx, +- "pendingBuf overflow"); ++ /* Check that the overlay between pending_buf and sym_buf is ok: */ ++ Assert(s->pending < s->lit_bufsize + sx, "pendingBuf overflow"); +=20 +- } while (lx < s->last_lit); ++ } while (sx < s->sym_next); +=20 + send_code(s, END_BLOCK, ltree); + } --=20 2.34.1 --===============1850201643795595007==--