diff -Nru bzip2-1.0.6/debian/changelog bzip2-1.0.6/debian/changelog --- bzip2-1.0.6/debian/changelog 2019-06-24 18:36:06.000000000 +0000 +++ bzip2-1.0.6/debian/changelog 2019-07-04 12:28:07.000000000 +0000 @@ -1,3 +1,11 @@ +bzip2 (1.0.6-8ubuntu0.2) xenial-security; urgency=medium + + * SECURITY REGRESSION: bzip2 update for CVE-2019-12900 causes some files raises + incorrect CRC error. (LP: #1834494) + - debian/patches/Accept-as-many-selectors-as-selectors*.patch + + -- Leonidas S. Barbosa Thu, 04 Jul 2019 09:27:38 -0300 + bzip2 (1.0.6-8ubuntu0.1) xenial-security; urgency=medium * SECURITY UPDATE: Denial of service diff -Nru bzip2-1.0.6/debian/patches/Accept-as-many-selectors-as-the-file-format-allows.patch bzip2-1.0.6/debian/patches/Accept-as-many-selectors-as-the-file-format-allows.patch --- bzip2-1.0.6/debian/patches/Accept-as-many-selectors-as-the-file-format-allows.patch 1970-01-01 00:00:00.000000000 +0000 +++ bzip2-1.0.6/debian/patches/Accept-as-many-selectors-as-the-file-format-allows.patch 2019-07-04 12:27:26.000000000 +0000 @@ -0,0 +1,73 @@ +From b357f4ec14a8b5b11b37621ee9f2a10f518b6c65 Mon Sep 17 00:00:00 2001 +From: Mark Wielaard +Date: Wed, 3 Jul 2019 01:28:11 +0200 +Subject: [PATCH] Accept as many selectors as the file format allows. + +But ignore any larger than the theoretical maximum, BZ_MAX_SELECTORS. + +The theoretical maximum number of selectors depends on the maximum +blocksize (900000 bytes) and the number of symbols (50) that can be +encoded with a different Huffman tree. BZ_MAX_SELECTORS is 18002. + +But the bzip2 file format allows the number of selectors to be encoded +with 15 bits (because 18002 isn't a factor of 2 and doesn't fit in +14 bits). So the file format maximum is 32767 selectors. + +Some bzip2 encoders might actually have written out more selectors +than the theoretical maximum because they rounded up the number of +selectors to some convenient factor of 8. + +The extra 14766 selectors can never be validly used by the decompression +algorithm. So we can read them, but then discard them. + +This is effectively what was done (by accident) before we added a +check for nSelectors to be at most BZ_MAX_SELECTORS to mitigate +CVE-2019-12900. + +The extra selectors were written out after the array inside the +EState struct. But the struct has extra space allocated after the +selector arrays of 18060 bytes (which is larger than 14766). +All of which will be initialized later (so the overwrite of that +space with extra selector values would have been harmless). +diff --git a/compress.c b/compress.c +index caf7696..19b662b 100644 +--- a/compress.c ++++ b/compress.c +@@ -454,7 +454,7 @@ void sendMTFValues ( EState* s ) + + AssertH( nGroups < 8, 3002 ); + AssertH( nSelectors < 32768 && +- nSelectors <= (2 + (900000 / BZ_G_SIZE)), ++ nSelectors <= BZ_MAX_SELECTORS, + 3003 ); + + +diff --git a/decompress.c b/decompress.c +index b6e0a29..78060c9 100644 +--- a/decompress.c ++++ b/decompress.c +@@ -287,7 +287,7 @@ Int32 BZ2_decompress ( DState* s ) + GET_BITS(BZ_X_SELECTOR_1, nGroups, 3); + if (nGroups < 2 || nGroups > 6) RETURN(BZ_DATA_ERROR); + GET_BITS(BZ_X_SELECTOR_2, nSelectors, 15); +- if (nSelectors < 1 || nSelectors > BZ_MAX_SELECTORS) RETURN(BZ_DATA_ERROR); ++ if (nSelectors < 1) RETURN(BZ_DATA_ERROR); + for (i = 0; i < nSelectors; i++) { + j = 0; + while (True) { +@@ -296,8 +296,14 @@ Int32 BZ2_decompress ( DState* s ) + j++; + if (j >= nGroups) RETURN(BZ_DATA_ERROR); + } +- s->selectorMtf[i] = j; ++ /* Having more than BZ_MAX_SELECTORS doesn't make much sense ++ since they will never be used, but some implementations might ++ "round up" the number of selectors, so just ignore those. */ ++ if (i < BZ_MAX_SELECTORS) ++ s->selectorMtf[i] = j; + } ++ if (nSelectors > BZ_MAX_SELECTORS) ++ nSelectors = BZ_MAX_SELECTORS; + + /*--- Undo the MTF values for the selectors. ---*/ + { diff -Nru bzip2-1.0.6/debian/patches/series bzip2-1.0.6/debian/patches/series --- bzip2-1.0.6/debian/patches/series 2019-06-24 18:31:52.000000000 +0000 +++ bzip2-1.0.6/debian/patches/series 2019-07-04 12:27:26.000000000 +0000 @@ -3,3 +3,4 @@ 30-bzip2-harden.patch CVE-2016-3189.patch CVE-2019-12900.patch +Accept-as-many-selectors-as-the-file-format-allows.patch