~ruther/guix-local

5b327a2d6192adbabb5b98bc3a78eb8402bd6d1d — Leo Famulari 8 years ago 1ee13e0
gnu: exim: Fix CVE-2017-16943.

* gnu/packages/patches/exim-CVE-2017-16943.patch: New file.
* gnu/local.mk (dist_patch_DATA): Add it.
* gnu/packages/mail.scm (exim)[source]: Use it.
3 files changed, 68 insertions(+), 1 deletions(-)

M gnu/local.mk
M gnu/packages/mail.scm
A gnu/packages/patches/exim-CVE-2017-16943.patch
M gnu/local.mk => gnu/local.mk +1 -0
@@ 614,6 614,7 @@ dist_patch_DATA =						\
  %D%/packages/patches/erlang-man-path.patch			\
  %D%/packages/patches/eudev-rules-directory.patch		\
  %D%/packages/patches/evilwm-lost-focus-bug.patch		\
  %D%/packages/patches/exim-CVE-2017-16943.patch		\
  %D%/packages/patches/exim-CVE-2017-1000369.patch		\
  %D%/packages/patches/exiv2-CVE-2017-14860.patch		\
  %D%/packages/patches/exiv2-CVE-2017-14859-14862-14864.patch	\

M gnu/packages/mail.scm => gnu/packages/mail.scm +2 -1
@@ 1042,7 1042,8 @@ delivery.")
                                 version ".tar.bz2")
                  (string-append "ftp://ftp.exim.org/pub/exim/exim4/old/exim-"
                                 version ".tar.bz2")))
       (patches (search-patches "exim-CVE-2017-1000369.patch"))
       (patches (search-patches "exim-CVE-2017-16943.patch"
                                "exim-CVE-2017-1000369.patch"))
       (sha256
        (base32
         "1c0syp7yxngmq7y8vqsrvijinzin5m941vn0ljihdfld7kh2wbwi"))))

A gnu/packages/patches/exim-CVE-2017-16943.patch => gnu/packages/patches/exim-CVE-2017-16943.patch +65 -0
@@ 0,0 1,65 @@
Fix CVE-2017-16943:

https://bugs.exim.org/show_bug.cgi?id=2199
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2017-16943

Patch copied from upstream source repository:

https://git.exim.org/exim.git/commit/4090d62a4b25782129cc1643596dc2f6e8f63bde

From 4090d62a4b25782129cc1643596dc2f6e8f63bde Mon Sep 17 00:00:00 2001
From: Jeremy Harris <jgh146exb@wizmail.org>
Date: Fri, 24 Nov 2017 20:22:33 +0000
Subject: [PATCH] Avoid release of store if there have been later allocations. 
 Bug 2199

---
 doc/doc-txt/ChangeLog | 4 ++++
 src/src/receive.c     | 7 ++++---
 2 files changed, 8 insertions(+), 3 deletions(-)

#diff --git a/doc/doc-txt/ChangeLog b/doc/doc-txt/ChangeLog
#index e937ba2..a2d9339 100644
#--- a/doc/doc-txt/ChangeLog
#+++ b/doc/doc-txt/ChangeLog
#@@ -59,6 +59,10 @@ JH/30 Fix a logging bug on aarch64: an unsafe routine was previously used for
#       connection in response to HELO" was logged instead of the actual 4xx
#       error for the HELO.
# 
#+JH/34 Bug 2199: fix a use-after-free while reading smtp input for header lines.
#+      A crafted sequence of BDAT commands could result in in-use memory beeing
#+      freed.
#+
# 
 Exim version 4.89
 -----------------
diff --git a/src/src/receive.c b/src/src/receive.c
index 95cf13e..20672db 100644
--- a/src/receive.c
+++ b/src/receive.c
@@ -1772,8 +1772,8 @@ for (;;)
   (and sometimes lunatic messages can have ones that are 100s of K long) we
   call store_release() for strings that have been copied - if the string is at
   the start of a block (and therefore the only thing in it, because we aren't
-  doing any other gets), the block gets freed. We can only do this because we
-  know there are no other calls to store_get() going on. */
+  doing any other gets), the block gets freed. We can only do this release if
+  there were no allocations since the once that we want to free. */
 
   if (ptr >= header_size - 4)
     {
@@ -1782,9 +1782,10 @@ for (;;)
     header_size *= 2;
     if (!store_extend(next->text, oldsize, header_size))
       {
+      BOOL release_ok = store_last_get[store_pool] == next->text;
       uschar *newtext = store_get(header_size);
       memcpy(newtext, next->text, ptr);
-      store_release(next->text);
+      if (release_ok) store_release(next->text);
       next->text = newtext;
       }
     }
-- 
1.9.1