[PATCH 0/1] More libxml2 security fixes

[PATCH 0/1] More libxml2 security fixes

[Leo Famulari]

libxml2 2.9.4 is released, with a lot of fixed bugs, both with and
without CVE IDs:

https://git.gnome.org/browse/libxml2/log/

This patch updates the existing graft by removing patches for two of
these fixed bugs, and updating to 2.9.4, fixing 10 additional CVE bugs.

The question is: will it work to graft 2.9.4 in place of 2.9.3?

Can anyone recommend a package that uses libxml2 in an obvious way (e.g.
for parsing an XML configuration file)?

Leo Famulari (1):
  gnu: libxml2: Update replacement to 2.9.4 [security fixes].

 gnu/local.mk                                     |  2 -
 gnu/packages/patches/libxml2-CVE-2016-3627.patch | 61 ---------------------
 gnu/packages/patches/libxml2-CVE-2016-3705.patch | 68 ------------------------
 gnu/packages/xml.scm                             | 14 +++--
 4 files changed, 10 insertions(+), 135 deletions(-)
 delete mode 100644 gnu/packages/patches/libxml2-CVE-2016-3627.patch
 delete mode 100644 gnu/packages/patches/libxml2-CVE-2016-3705.patch

-- 
2.8.3

[PATCH 1/1] gnu: libxml2: Update replacement to 2.9.4 [security fixes].

[Leo Famulari]

This fixes CVE-2016-{1762, 1833, 1834, 1835, 1836, 1837, 1838, 1839,
1840, 3627, 3705, 4483}.

* gnu/packages/patches/libxml2-CVE-2016-3627.patch,
gnu/packages/patches/libxml2-CVE-2016-3705.patch: Delete files.
* gnu/local.mk (dist_patch_DATA): Remove them.
* gnu/packages/xml.scm (libxml2/fixed): Update to 2.9.4.
[source]: Remove patches.
---
 gnu/local.mk                                     |  2 -
 gnu/packages/patches/libxml2-CVE-2016-3627.patch | 61 ---------------------
 gnu/packages/patches/libxml2-CVE-2016-3705.patch | 68 ------------------------
 gnu/packages/xml.scm                             | 14 +++--
 4 files changed, 10 insertions(+), 135 deletions(-)
 delete mode 100644 gnu/packages/patches/libxml2-CVE-2016-3627.patch
 delete mode 100644 gnu/packages/patches/libxml2-CVE-2016-3705.patch

diff --git a/gnu/local.mk b/gnu/local.mk
index f36389f..037264b 100644
--- a/gnu/local.mk
+++ b/gnu/local.mk
@@ -607,8 +607,6 @@ dist_patch_DATA =						\
   %D%/packages/patches/libwmf-CVE-2015-0848+CVE-2015-4588.patch	\
   %D%/packages/patches/libwmf-CVE-2015-4695.patch		\
   %D%/packages/patches/libwmf-CVE-2015-4696.patch		\
-  %D%/packages/patches/libxml2-CVE-2016-3627.patch		\
-  %D%/packages/patches/libxml2-CVE-2016-3705.patch		\
   %D%/packages/patches/libxslt-CVE-2015-7995.patch		\
   %D%/packages/patches/lirc-localstatedir.patch			\
   %D%/packages/patches/libpthread-glibc-preparation.patch	\
diff --git a/gnu/packages/patches/libxml2-CVE-2016-3627.patch b/gnu/packages/patches/libxml2-CVE-2016-3627.patch
deleted file mode 100644
index 782c927..0000000
--- a/gnu/packages/patches/libxml2-CVE-2016-3627.patch
+++ /dev/null
@@ -1,61 +0,0 @@
-From <http://seclists.org/fulldisclosure/2016/May/10>.
-
-From e5269fd1e83743f7e62c89eca45000c2e84e6edc Mon Sep 17 00:00:00 2001
-From: Peter Simons <psimons () suse com>
-Date: Thu, 14 Apr 2016 16:15:13 +0200
-Subject: [PATCH 1/2] xmlStringGetNodeList: limit the function to 1024
- recursions to avoid CVE-2016-3627
-
-This patch prevents stack overflows like the one reported in
-https://bugzilla.gnome.org/show_bug.cgi?id=762100.
----
- tree.c | 14 ++++++++++++--
- 1 file changed, 12 insertions(+), 2 deletions(-)
-
-Index: libxml2-2.9.3/tree.c
-===================================================================
---- libxml2-2.9.3.orig/tree.c
-+++ libxml2-2.9.3/tree.c
-@@ -1464,6 +1464,8 @@ out:
-     return(ret);
- }
- 
-+static xmlNodePtr xmlStringGetNodeListInternal(const xmlDoc *doc, const xmlChar *value, size_t recursionLevel);
-+
- /**
-  * xmlStringGetNodeList:
-  * @doc:  the document
-@@ -1475,6 +1477,12 @@ out:
-  */
- xmlNodePtr
- xmlStringGetNodeList(const xmlDoc *doc, const xmlChar *value) {
-+   return xmlStringGetNodeListInternal(doc, value, 0);
-+ }
-+
-+xmlNodePtr
-+xmlStringGetNodeListInternal(const xmlDoc *doc, const xmlChar *value, size_t recursionLevel) {
-+
-     xmlNodePtr ret = NULL, last = NULL;
-     xmlNodePtr node;
-     xmlChar *val;
-@@ -1483,6 +1491,8 @@ xmlStringGetNodeList(const xmlDoc *doc,
-     xmlEntityPtr ent;
-     xmlBufPtr buf;
- 
-+    if (recursionLevel > 1024) return(NULL);
-+
-     if (value == NULL) return(NULL);
- 
-     buf = xmlBufCreateSize(0);
-@@ -1593,8 +1603,9 @@ xmlStringGetNodeList(const xmlDoc *doc,
- 			else if ((ent != NULL) && (ent->children == NULL)) {
- 			    xmlNodePtr temp;
- 
--			    ent->children = xmlStringGetNodeList(doc,
--				    (const xmlChar*)node->content);
-+			    ent->children = xmlStringGetNodeListInternal(doc,
-+				    (const xmlChar*)node->content,
-+                                    recursionLevel+1);
- 			    ent->owner = 1;
- 			    temp = ent->children;
- 			    while (temp) {
diff --git a/gnu/packages/patches/libxml2-CVE-2016-3705.patch b/gnu/packages/patches/libxml2-CVE-2016-3705.patch
deleted file mode 100644
index e803630..0000000
--- a/gnu/packages/patches/libxml2-CVE-2016-3705.patch
+++ /dev/null
@@ -1,68 +0,0 @@
-From <http://seclists.org/fulldisclosure/2016/May/10>.
-
-From 6f0af3f6b9b1c5f82a2bb5ded65923437fee5d21 Mon Sep 17 00:00:00 2001
-From: Peter Simons <psimons () suse com>
-Date: Fri, 15 Apr 2016 11:56:55 +0200
-Subject: [PATCH 2/2] Add missing increments of recursion depth counter to XML
- parser.
-
-The functions xmlParserEntityCheck() and xmlParseAttValueComplex() used to call
-xmlStringDecodeEntities() in a recursive context without incrementing the
-'depth' counter in the parser context. Because of that omission, the parser
-failed to detect attribute recursions in certain documents before running out
-of stack space.
----
- parser.c | 8 ++++++++
- 1 file changed, 8 insertions(+)
-
-diff --git a/parser.c b/parser.c
-index 9604a72..4da151f 100644
---- a/parser.c
-+++ b/parser.c
-@@ -144,8 +144,10 @@ xmlParserEntityCheck(xmlParserCtxtPtr ctxt, size_t size,
- 
- 	ent->checked = 1;
- 
-+        ++ctxt->depth;
- 	rep = xmlStringDecodeEntities(ctxt, ent->content,
- 				  XML_SUBSTITUTE_REF, 0, 0, 0);
-+        --ctxt->depth;
- 
- 	ent->checked = (ctxt->nbentities - oldnbent + 1) * 2;
- 	if (rep != NULL) {
-@@ -3966,8 +3968,10 @@ xmlParseEntityValue(xmlParserCtxtPtr ctxt, xmlChar **orig) {
- 	 * an entity declaration, it is bypassed and left as is.
- 	 * so XML_SUBSTITUTE_REF is not set here.
- 	 */
-+        ++ctxt->depth;
- 	ret = xmlStringDecodeEntities(ctxt, buf, XML_SUBSTITUTE_PEREF,
- 				      0, 0, 0);
-+        --ctxt->depth;
- 	if (orig != NULL)
- 	    *orig = buf;
- 	else
-@@ -4092,9 +4096,11 @@ xmlParseAttValueComplex(xmlParserCtxtPtr ctxt, int *attlen, int normalize) {
- 		} else if ((ent != NULL) &&
- 		           (ctxt->replaceEntities != 0)) {
- 		    if (ent->etype != XML_INTERNAL_PREDEFINED_ENTITY) {
-+			++ctxt->depth;
- 			rep = xmlStringDecodeEntities(ctxt, ent->content,
- 						      XML_SUBSTITUTE_REF,
- 						      0, 0, 0);
-+			--ctxt->depth;
- 			if (rep != NULL) {
- 			    current = rep;
- 			    while (*current != 0) { /* non input consuming */
-@@ -4130,8 +4136,10 @@ xmlParseAttValueComplex(xmlParserCtxtPtr ctxt, int *attlen, int normalize) {
- 			(ent->content != NULL) && (ent->checked == 0)) {
- 			unsigned long oldnbent = ctxt->nbentities;
- 
-+			++ctxt->depth;
- 			rep = xmlStringDecodeEntities(ctxt, ent->content,
- 						  XML_SUBSTITUTE_REF, 0, 0, 0);
-+			--ctxt->depth;
- 
- 			ent->checked = (ctxt->nbentities - oldnbent + 1) * 2;
- 			if (rep != NULL) {
--- 
-2.8.1
diff --git a/gnu/packages/xml.scm b/gnu/packages/xml.scm
index 782e356..dc5c60d 100644
--- a/gnu/packages/xml.scm
+++ b/gnu/packages/xml.scm
@@ -107,10 +107,16 @@ project (but it is usable outside of the Gnome platform).")
 (define libxml2/fixed
   (package
     (inherit libxml2)
-    (source (origin
-              (inherit (package-source libxml2))
-              (patches (search-patches "libxml2-CVE-2016-3627.patch"
-                                       "libxml2-CVE-2016-3705.patch"))))))
+    (source
+     (let ((name "libxml2")
+           (version "2.9.4"))
+       (origin
+         (method url-fetch)
+         (uri (string-append "ftp://xmlsoft.org/libxml2/libxml2-"
+                             version ".tar.gz"))
+         (sha256
+          (base32
+           "0g336cr0bw6dax1q48bblphmchgihx9p1pjmxdnrd6sh3qci3fgz")))))))
 
 (define-public python-libxml2
   (package (inherit libxml2)
-- 
2.8.3

Re: [PATCH 1/1] gnu: libxml2: Update replacement to 2.9.4 [security fixes].

[Ludovic Courtès]

Leo Famulari <leo@famulari.name> skribis:

> This fixes CVE-2016-{1762, 1833, 1834, 1835, 1836, 1837, 1838, 1839,
> 1840, 3627, 3705, 4483}.
>
> * gnu/packages/patches/libxml2-CVE-2016-3627.patch,
> gnu/packages/patches/libxml2-CVE-2016-3705.patch: Delete files.
> * gnu/local.mk (dist_patch_DATA): Remove them.
> * gnu/packages/xml.scm (libxml2/fixed): Update to 2.9.4.
> [source]: Remove patches.

If this is claimed to be ABI-compatible with 2.9.3, fine with me.

Thanks for looking into it!

Ludo’.

Re: [PATCH 1/1] gnu: libxml2: Update replacement to 2.9.4 [security fixes].

[Leo Famulari]

On Sat, May 28, 2016 at 05:33:26PM +0200, Ludovic Courtès wrote:
> Leo Famulari <leo@famulari.name> skribis:
> 
> > This fixes CVE-2016-{1762, 1833, 1834, 1835, 1836, 1837, 1838, 1839,
> > 1840, 3627, 3705, 4483}.
> >
> > * gnu/packages/patches/libxml2-CVE-2016-3627.patch,
> > gnu/packages/patches/libxml2-CVE-2016-3705.patch: Delete files.
> > * gnu/local.mk (dist_patch_DATA): Remove them.
> > * gnu/packages/xml.scm (libxml2/fixed): Update to 2.9.4.
> > [source]: Remove patches.
> 
> If this is claimed to be ABI-compatible with 2.9.3, fine with me.

I've asked this question on xml@gnome.org, the relevant mailing list.
Waiting for a response...

Re: [PATCH 1/1] gnu: libxml2: Update replacement to 2.9.4 [security fixes].

[Leo Famulari]

On Sat, May 28, 2016 at 05:33:26PM +0200, Ludovic Courtès wrote:
> Leo Famulari <leo@famulari.name> skribis:
> 
> > This fixes CVE-2016-{1762, 1833, 1834, 1835, 1836, 1837, 1838, 1839,
> > 1840, 3627, 3705, 4483}.
> >
> > * gnu/packages/patches/libxml2-CVE-2016-3627.patch,
> > gnu/packages/patches/libxml2-CVE-2016-3705.patch: Delete files.
> > * gnu/local.mk (dist_patch_DATA): Remove them.
> > * gnu/packages/xml.scm (libxml2/fixed): Update to 2.9.4.
> > [source]: Remove patches.
> 
> If this is claimed to be ABI-compatible with 2.9.3, fine with me.

After a few days with no reply on the upstream mailing list, and with no
problems after reconfiguring my GuixSD GNOME system with this patch, I
applied it as df2dd07b88.

https://mail.gnome.org/archives/xml/2016-May/msg00031.html