From 643597a5c432b2e02033d0cefa3ba4da980d078f Mon Sep 17 00:00:00 2001 From: Joe MacDonald Date: Mon, 20 Oct 2014 13:51:21 -0400 Subject: libxml2: fix CVE-2014-3660 It was discovered that the patch for CVE-2014-0191 for libxml2 is incomplete. It is still possible to have libxml2 incorrectly perform entity substituton even when the application using libxml2 explicitly disables the feature. This can allow a remote denial-of-service attack on systems with libxml2 prior to 2.9.2. References: http://www.openwall.com/lists/oss-security/2014/10/17/7 https://www.ncsc.nl/actueel/nieuwsberichten/kwetsbaarheid-ontdekt-in-libxml2.html Signed-off-by: Joe MacDonald Signed-off-by: Ross Burton --- meta/recipes-core/libxml/libxml2.inc | 1 + .../libxml/libxml2/libxml2-CVE-2014-3660.patch | 147 +++++++++++++++++++++ 2 files changed, 148 insertions(+) create mode 100644 meta/recipes-core/libxml/libxml2/libxml2-CVE-2014-3660.patch diff --git a/meta/recipes-core/libxml/libxml2.inc b/meta/recipes-core/libxml/libxml2.inc index bcf9a62ded..c729c199cf 100644 --- a/meta/recipes-core/libxml/libxml2.inc +++ b/meta/recipes-core/libxml/libxml2.inc @@ -21,6 +21,7 @@ SRC_URI = "ftp://xmlsoft.org/libxml2/libxml2-${PV}.tar.gz;name=libtar \ file://libxml2-CVE-2014-0191-fix.patch \ file://python-sitepackages-dir.patch \ file://libxml-m4-use-pkgconfig.patch \ + file://libxml2-CVE-2014-3660.patch \ " BINCONFIG = "${bindir}/xml2-config" diff --git a/meta/recipes-core/libxml/libxml2/libxml2-CVE-2014-3660.patch b/meta/recipes-core/libxml/libxml2/libxml2-CVE-2014-3660.patch new file mode 100644 index 0000000000..b9621c93eb --- /dev/null +++ b/meta/recipes-core/libxml/libxml2/libxml2-CVE-2014-3660.patch @@ -0,0 +1,147 @@ +From be2a7edaf289c5da74a4f9ed3a0b6c733e775230 Mon Sep 17 00:00:00 2001 +From: Daniel Veillard +Date: Thu, 16 Oct 2014 13:59:47 +0800 +Subject: Fix for CVE-2014-3660 + +Issues related to the billion laugh entity expansion which happened to +escape the initial set of fixes + +Upstream-status: Backport +Reference: https://git.gnome.org/browse/libxml2/commit/?id=be2a7edaf289c5da74a4f9ed3a0b6c733e775230&context=3&ignorews=0&ss=0 + +Signed-off-by: Joe MacDonald + +diff --git a/parser.c b/parser.c +index f51e8d2..1d93967 100644 +--- a/parser.c ++++ b/parser.c +@@ -130,6 +130,29 @@ xmlParserEntityCheck(xmlParserCtxtPtr ctxt, size_t size, + return (0); + if (ctxt->lastError.code == XML_ERR_ENTITY_LOOP) + return (1); ++ ++ /* ++ * This may look absurd but is needed to detect ++ * entities problems ++ */ ++ if ((ent != NULL) && (ent->etype != XML_INTERNAL_PREDEFINED_ENTITY) && ++ (ent->content != NULL) && (ent->checked == 0)) { ++ unsigned long oldnbent = ctxt->nbentities; ++ xmlChar *rep; ++ ++ ent->checked = 1; ++ ++ rep = xmlStringDecodeEntities(ctxt, ent->content, ++ XML_SUBSTITUTE_REF, 0, 0, 0); ++ ++ ent->checked = (ctxt->nbentities - oldnbent + 1) * 2; ++ if (rep != NULL) { ++ if (xmlStrchr(rep, '<')) ++ ent->checked |= 1; ++ xmlFree(rep); ++ rep = NULL; ++ } ++ } + if (replacement != 0) { + if (replacement < XML_MAX_TEXT_LENGTH) + return(0); +@@ -189,9 +212,12 @@ xmlParserEntityCheck(xmlParserCtxtPtr ctxt, size_t size, + return (0); + } else { + /* +- * strange we got no data for checking just return ++ * strange we got no data for checking + */ +- return (0); ++ if (((ctxt->lastError.code != XML_ERR_UNDECLARED_ENTITY) && ++ (ctxt->lastError.code != XML_WAR_UNDECLARED_ENTITY)) || ++ (ctxt->nbentities <= 10000)) ++ return (0); + } + xmlFatalErr(ctxt, XML_ERR_ENTITY_LOOP, NULL); + return (1); +@@ -2589,6 +2615,7 @@ xmlParserHandlePEReference(xmlParserCtxtPtr ctxt) { + name, NULL); + ctxt->valid = 0; + } ++ xmlParserEntityCheck(ctxt, 0, NULL, 0); + } else if (ctxt->input->free != deallocblankswrapper) { + input = xmlNewBlanksWrapperInputStream(ctxt, entity); + if (xmlPushInput(ctxt, input) < 0) +@@ -2759,6 +2786,7 @@ xmlStringLenDecodeEntities(xmlParserCtxtPtr ctxt, const xmlChar *str, int len, + if ((ctxt->lastError.code == XML_ERR_ENTITY_LOOP) || + (ctxt->lastError.code == XML_ERR_INTERNAL_ERROR)) + goto int_error; ++ xmlParserEntityCheck(ctxt, 0, ent, 0); + if (ent != NULL) + ctxt->nbentities += ent->checked / 2; + if ((ent != NULL) && +@@ -2810,6 +2838,7 @@ xmlStringLenDecodeEntities(xmlParserCtxtPtr ctxt, const xmlChar *str, int len, + ent = xmlParseStringPEReference(ctxt, &str); + if (ctxt->lastError.code == XML_ERR_ENTITY_LOOP) + goto int_error; ++ xmlParserEntityCheck(ctxt, 0, ent, 0); + if (ent != NULL) + ctxt->nbentities += ent->checked / 2; + if (ent != NULL) { +@@ -7312,6 +7341,7 @@ xmlParseReference(xmlParserCtxtPtr ctxt) { + (ret != XML_WAR_UNDECLARED_ENTITY)) { + xmlFatalErrMsgStr(ctxt, XML_ERR_UNDECLARED_ENTITY, + "Entity '%s' failed to parse\n", ent->name); ++ xmlParserEntityCheck(ctxt, 0, ent, 0); + } else if (list != NULL) { + xmlFreeNodeList(list); + list = NULL; +@@ -7418,7 +7448,7 @@ xmlParseReference(xmlParserCtxtPtr ctxt) { + /* + * We are copying here, make sure there is no abuse + */ +- ctxt->sizeentcopy += ent->length; ++ ctxt->sizeentcopy += ent->length + 5; + if (xmlParserEntityCheck(ctxt, 0, ent, ctxt->sizeentcopy)) + return; + +@@ -7466,7 +7496,7 @@ xmlParseReference(xmlParserCtxtPtr ctxt) { + /* + * We are copying here, make sure there is no abuse + */ +- ctxt->sizeentcopy += ent->length; ++ ctxt->sizeentcopy += ent->length + 5; + if (xmlParserEntityCheck(ctxt, 0, ent, ctxt->sizeentcopy)) + return; + +@@ -7652,6 +7682,7 @@ xmlParseEntityRef(xmlParserCtxtPtr ctxt) { + ctxt->sax->reference(ctxt->userData, name); + } + } ++ xmlParserEntityCheck(ctxt, 0, ent, 0); + ctxt->valid = 0; + } + +@@ -7845,6 +7876,7 @@ xmlParseStringEntityRef(xmlParserCtxtPtr ctxt, const xmlChar ** str) { + "Entity '%s' not defined\n", + name); + } ++ xmlParserEntityCheck(ctxt, 0, ent, 0); + /* TODO ? check regressions ctxt->valid = 0; */ + } + +@@ -8004,6 +8036,7 @@ xmlParsePEReference(xmlParserCtxtPtr ctxt) + name, NULL); + ctxt->valid = 0; + } ++ xmlParserEntityCheck(ctxt, 0, NULL, 0); + } else { + /* + * Internal checking in case the entity quest barfed +@@ -8243,6 +8276,7 @@ xmlParseStringPEReference(xmlParserCtxtPtr ctxt, const xmlChar **str) { + name, NULL); + ctxt->valid = 0; + } ++ xmlParserEntityCheck(ctxt, 0, NULL, 0); + } else { + /* + * Internal checking in case the entity quest barfed +-- +cgit v0.10.1 + -- cgit 1.2.3-korg