mirror of
https://git.busybox.net/buildroot.git
synced 2024-12-11 22:33:29 +08:00
59 lines
2.1 KiB
Diff
59 lines
2.1 KiB
Diff
|
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: [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 <samuel.sapalski@nokia.com>
|
||
|
|
Signed-off-by: Peter Kaestle <peter.kaestle@nokia.com>
|
||
|
|
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
|
||
|
|
Signed-off-by: Peter Korsgaard <peter@korsgaard.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)
|
||
|
|
--
|
||
|
|
2.20.1
|
||
|
|
|