01/02: gnu: busybox: Fix CVE-2021-28831.

[guix-commits]

lle_bout pushed a commit to branch master
in repository guix.

commit 572528e7ddcf6af213c78e70eb60953a82b96a96
Author: Léo Le Bouter <lle-bout@zaclys.net>
AuthorDate: Fri Mar 19 11:56:38 2021 +0100

    gnu: busybox: Fix CVE-2021-28831.
    
    * gnu/packages/patches/busybox-CVE-2021-28831.patch: New patch.
    * gnu/local.mk (dist_patch_DATA): Register it.
    * gnu/packages/busybox.scm (busybox): Apply it.
---
 gnu/local.mk                                      |  1 +
 gnu/packages/busybox.scm                          |  3 +-
 gnu/packages/patches/busybox-CVE-2021-28831.patch | 57 +++++++++++++++++++++++
 3 files changed, 60 insertions(+), 1 deletion(-)

diff --git a/gnu/local.mk b/gnu/local.mk
index afd9c17..8325c07 100644
--- a/gnu/local.mk
+++ b/gnu/local.mk
@@ -872,6 +872,7 @@ dist_patch_DATA =                                           
\
   %D%/packages/patches/blender-2.79-python-3.7-fix.patch       \
   %D%/packages/patches/blender-2.79-python-3.8-fix.patch       \
   %D%/packages/patches/bpftrace-disable-bfd-disasm.patch       \
+  %D%/packages/patches/busybox-CVE-2021-28831.patch            \
   %D%/packages/patches/byobu-writable-status.patch             \
   %D%/packages/patches/cairo-CVE-2018-19876.patch              \
   %D%/packages/patches/cairo-CVE-2020-35492.patch              \
diff --git a/gnu/packages/busybox.scm b/gnu/packages/busybox.scm
index 5af67e0..17c90c3 100644
--- a/gnu/packages/busybox.scm
+++ b/gnu/packages/busybox.scm
@@ -41,7 +41,8 @@
                     version ".tar.bz2"))
               (sha256
                (base32
-                "1vhd59qmrdyrr1q7rvxmyl96z192mxl089hi87yl0hcp6fyw8mwx"))))
+                "1vhd59qmrdyrr1q7rvxmyl96z192mxl089hi87yl0hcp6fyw8mwx"))
+              (patches (search-patches "busybox-CVE-2021-28831.patch"))))
     (build-system gnu-build-system)
     (arguments
      '(#:phases
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 0000000..da3107f
--- /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
+