From 1f2cf291e767f2472d95ccee19c4d97bdc00f3d6 Mon Sep 17 00:00:00 2001 From: Pavel Zhukov Date: Wed, 1 Dec 2021 10:54:36 +0100 Subject: busybox: Fix for CVE-2021-42374 An out-of-bounds heap read in unlzma leads to information leak and denial of service when crafted LZMA-compressed input is decompressed. This can be triggered by any applet/format that internally supports LZMA compression. Reference: https://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2021-42374 (From OE-Core rev: 297719989ebe8ce7d50e3991cba3e268938690ce) Signed-off-by: Pavel Zhukov Signed-off-by: Steve Sakoman Signed-off-by: Richard Purdie --- .../busybox/busybox/CVE-2021-42374.patch | 53 ++++++++++++++++++++++ meta/recipes-core/busybox/busybox_1.31.1.bb | 1 + 2 files changed, 54 insertions(+) create mode 100644 meta/recipes-core/busybox/busybox/CVE-2021-42374.patch diff --git a/meta/recipes-core/busybox/busybox/CVE-2021-42374.patch b/meta/recipes-core/busybox/busybox/CVE-2021-42374.patch new file mode 100644 index 0000000000..aef8a3db85 --- /dev/null +++ b/meta/recipes-core/busybox/busybox/CVE-2021-42374.patch @@ -0,0 +1,53 @@ +From 04f052c56ded5ab6a904e3a264a73dc0412b2e78 Mon Sep 17 00:00:00 2001 +From: Denys Vlasenko +Date: Tue, 15 Jun 2021 15:07:57 +0200 +Subject: [PATCH] unlzma: fix a case where we could read before beginning of + buffer +Cc: pavel@zhukoff.net + +Testcase: + + 21 01 01 00 00 00 00 00 e7 01 01 01 ef 00 df b6 + 00 17 02 10 11 0f ff 00 16 00 00 + +Unfortunately, the bug is not reliably causing a segfault, +the behavior depends on what's in memory before the buffer. + +function old new delta +unpack_lzma_stream 2762 2768 +6 + +Signed-off-by: Denys Vlasenko + +Signed-off-by: Pavel Zhukov + +CVE: CVE-2021-42374 +Upstream-Status: Backport [https://git.busybox.net/busybox/commit/?h=1_33_stable&id=d326be2850ea2bd78fe2c22d6c45c3b861d82937] +Comment: testdata dropped because of binary format + +--- + archival/libarchive/decompress_unlzma.c | 5 ++++- + testsuite/unlzma.tests | 17 +++++++++++++---- + testsuite/unlzma_issue_3.lzma | Bin 0 -> 27 bytes + 3 files changed, 17 insertions(+), 5 deletions(-) + create mode 100644 testsuite/unlzma_issue_3.lzma + +diff --git a/archival/libarchive/decompress_unlzma.c b/archival/libarchive/decompress_unlzma.c +index 0744f231a1d64d92676b0cada2342f88f3b39b31..fb5aac8fe9ea0c53e0c2d7a7cbd05a753e39bc9d 100644 +--- a/archival/libarchive/decompress_unlzma.c ++++ b/archival/libarchive/decompress_unlzma.c +@@ -290,8 +290,11 @@ unpack_lzma_stream(transformer_state_t *xstate) + uint32_t pos; + + pos = buffer_pos - rep0; +- if ((int32_t)pos < 0) ++ if ((int32_t)pos < 0) { + pos += header.dict_size; ++ if ((int32_t)pos < 0) ++ goto bad; ++ } + match_byte = buffer[pos]; + do { + int bit; +-- +2.34.0 + diff --git a/meta/recipes-core/busybox/busybox_1.31.1.bb b/meta/recipes-core/busybox/busybox_1.31.1.bb index d9d5f4f96b..55c00eb483 100644 --- a/meta/recipes-core/busybox/busybox_1.31.1.bb +++ b/meta/recipes-core/busybox/busybox_1.31.1.bb @@ -52,6 +52,7 @@ SRC_URI = "https://busybox.net/downloads/busybox-${PV}.tar.bz2;name=tarball \ file://0001-hwclock-make-glibc-2.31-compatible.patch \ file://0001-decompress_gunzip-Fix-DoS-if-gzip-is-corrupt.patch \ file://0001-mktemp-add-tmpdir-option.patch \ + file://CVE-2021-42374.patch \ " SRC_URI_append_libc-musl = " file://musl.cfg " -- cgit v1.2.3-54-g00ecf