From 147a08dced5e565f19f4987a3c199780dc00f878 Mon Sep 17 00:00:00 2001 From: Chen Qi Date: Wed, 7 Apr 2021 21:55:18 -0700 Subject: busybox: fix CVE-2021-28831 Backport patch to fix CVE-2021-28831. Signed-off-by: Chen Qi Signed-off-by: Richard Purdie (cherry picked from commit e579dbd9a6b2472ca90f411c0b594da9e38c9aca) Signed-off-by: Anuj Mittal --- ...ompress_gunzip-Fix-DoS-if-gzip-is-corrupt.patch | 58 ++++++++++++++++++++++ meta/recipes-core/busybox/busybox_1.32.0.bb | 3 +- 2 files changed, 60 insertions(+), 1 deletion(-) create mode 100644 meta/recipes-core/busybox/busybox/0001-decompress_gunzip-Fix-DoS-if-gzip-is-corrupt.patch diff --git a/meta/recipes-core/busybox/busybox/0001-decompress_gunzip-Fix-DoS-if-gzip-is-corrupt.patch b/meta/recipes-core/busybox/busybox/0001-decompress_gunzip-Fix-DoS-if-gzip-is-corrupt.patch new file mode 100644 index 0000000000..67c9f189cc --- /dev/null +++ b/meta/recipes-core/busybox/busybox/0001-decompress_gunzip-Fix-DoS-if-gzip-is-corrupt.patch @@ -0,0 +1,58 @@ +From fe791386ebc270219ca00406c9fdadc5130b64ee Mon Sep 17 00:00:00 2001 +From: Samuel Sapalski +Date: Wed, 3 Mar 2021 16:31:22 +0100 +Subject: [PATCH] decompress_gunzip: Fix DoS if gzip is corrupt + +On certain corrupt gzip files, huft_build will set the error bit on +the result pointer. If afterwards abort_unzip is called huft_free +might run into a segmentation fault or an invalid pointer to +free(p). + +In order to mitigate this, we check in huft_free if the error bit +is set and clear it before the linked list is freed. + +Signed-off-by: Samuel Sapalski +Signed-off-by: Peter Kaestle +Signed-off-by: Denys Vlasenko + +Upstream-Status: Backport +CVE: CVE-2021-28831 +Signed-off-by: Chen Qi +--- + archival/libarchive/decompress_gunzip.c | 12 ++++++++++-- + 1 file changed, 10 insertions(+), 2 deletions(-) + +diff --git a/archival/libarchive/decompress_gunzip.c b/archival/libarchive/decompress_gunzip.c +index eb3b64930..e93cd5005 100644 +--- a/archival/libarchive/decompress_gunzip.c ++++ b/archival/libarchive/decompress_gunzip.c +@@ -220,10 +220,20 @@ static const uint8_t border[] ALIGN1 = { + * each table. + * t: table to free + */ ++#define BAD_HUFT(p) ((uintptr_t)(p) & 1) ++#define ERR_RET ((huft_t*)(uintptr_t)1) + static void huft_free(huft_t *p) + { + huft_t *q; + ++ /* ++ * If 'p' has the error bit set we have to clear it, otherwise we might run ++ * into a segmentation fault or an invalid pointer to free(p) ++ */ ++ if (BAD_HUFT(p)) { ++ p = (huft_t*)((uintptr_t)(p) ^ (uintptr_t)(ERR_RET)); ++ } ++ + /* Go through linked list, freeing from the malloced (t[-1]) address. */ + while (p) { + q = (--p)->v.t; +@@ -289,8 +299,6 @@ static unsigned fill_bitbuffer(STATE_PARAM unsigned bitbuffer, unsigned *current + * or a valid pointer to a Huffman table, ORed with 0x1 if incompete table + * is given: "fixed inflate" decoder feeds us such data. + */ +-#define BAD_HUFT(p) ((uintptr_t)(p) & 1) +-#define ERR_RET ((huft_t*)(uintptr_t)1) + static huft_t* huft_build(const unsigned *b, const unsigned n, + const unsigned s, const struct cp_ext *cp_ext, + unsigned *m) diff --git a/meta/recipes-core/busybox/busybox_1.32.0.bb b/meta/recipes-core/busybox/busybox_1.32.0.bb index 8e23b0d4a2..b91f7cf711 100644 --- a/meta/recipes-core/busybox/busybox_1.32.0.bb +++ b/meta/recipes-core/busybox/busybox_1.32.0.bb @@ -46,7 +46,8 @@ SRC_URI = "https://busybox.net/downloads/busybox-${PV}.tar.bz2;name=tarball \ file://0001-hwclock-make-glibc-2.31-compatible.patch \ file://rev.cfg \ file://pgrep.cfg \ -" + file://0001-decompress_gunzip-Fix-DoS-if-gzip-is-corrupt.patch \ + " SRC_URI_append_libc-musl = " file://musl.cfg " SRC_URI[tarball.md5sum] = "9576986f1a960da471d03b72a62f13c7" -- cgit 1.2.3-korg