From 42098fd740fe3de68a221fcc9c44ead545757461 Mon Sep 17 00:00:00 2001 From: Chen Qi Date: Wed, 7 Jul 2021 14:37:48 +0530 Subject: busybox: fix CVE-2021-28831 Backport patch to fix CVE-2021-28831. (From OE-Core rev: e579dbd9a6b2472ca90f411c0b594da9e38c9aca) Signed-off-by: Chen Qi Signed-off-by: Richard Purdie Signed-off-by: Akash Hadke Signed-off-by: Steve Sakoman --- ...ompress_gunzip-Fix-DoS-if-gzip-is-corrupt.patch | 51 ++++++++++++++++++++++ meta/recipes-core/busybox/busybox_1.31.1.bb | 3 +- 2 files changed, 53 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..b75f0907e7 --- /dev/null +++ b/meta/recipes-core/busybox/busybox/0001-decompress_gunzip-Fix-DoS-if-gzip-is-corrupt.patch @@ -0,0 +1,51 @@ +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 +Comment: One hunk from this patch is removed as it was not relevant. +Signed-off-by: Chen Qi +Signed-off-by: Akash Hadke +--- + 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; diff --git a/meta/recipes-core/busybox/busybox_1.31.1.bb b/meta/recipes-core/busybox/busybox_1.31.1.bb index 7563368287..f7808f4d84 100644 --- a/meta/recipes-core/busybox/busybox_1.31.1.bb +++ b/meta/recipes-core/busybox/busybox_1.31.1.bb @@ -50,7 +50,8 @@ SRC_URI = "https://busybox.net/downloads/busybox-${PV}.tar.bz2;name=tarball \ file://0001-sysctl-ignore-EIO-of-stable_secret-below-proc-sys-ne.patch \ file://busybox-CVE-2018-1000500.patch \ file://0001-hwclock-make-glibc-2.31-compatible.patch \ -" + file://0001-decompress_gunzip-Fix-DoS-if-gzip-is-corrupt.patch \ + " SRC_URI_append_libc-musl = " file://musl.cfg " SRC_URI[tarball.md5sum] = "70913edaf2263a157393af07565c17f0" -- cgit 1.2.3-korg