diff options
Diffstat (limited to 'gnu/packages/patches/busybox-CVE-2021-28831.patch')
| -rw-r--r-- | gnu/packages/patches/busybox-CVE-2021-28831.patch | 57 |
1 files changed, 57 insertions, 0 deletions
diff --git a/gnu/packages/patches/busybox-CVE-2021-28831.patch b/gnu/packages/patches/busybox-CVE-2021-28831.patch new file mode 100644 index 0000000000..da3107fbb1 --- /dev/null +++ b/gnu/packages/patches/busybox-CVE-2021-28831.patch @@ -0,0 +1,57 @@ +From f25d254dfd4243698c31a4f3153d4ac72aa9e9bd Mon Sep 17 00:00:00 2001 +From: Samuel Sapalski <samuel.sapalski@nokia.com> +Date: Wed, 3 Mar 2021 16:31:22 +0100 +Subject: 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 <samuel.sapalski@nokia.com> +Signed-off-by: Peter Kaestle <peter.kaestle@nokia.com> +Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com> +--- + 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) +-- +cgit v1.2.1 + |