From: Deepak Rathore <[email protected]> These patches apply the upstream fixes shown in [1] and [2], as referenced by [3].
Upstream pull request mentioned in [4] contains both the storeAtts fix and the related xcsdup overflow hardening so adding both source patches explicit, even though the published advisory description names storeAtts specifically. [1] https://github.com/libexpat/libexpat/commit/12dc6d8d3d65f79471a94d8565f6bf1cf245f648 [2] https://github.com/libexpat/libexpat/commit/147c8f36d6277d5c6011c098370a8362aed47b15 [3] https://nvd.nist.gov/vuln/detail/CVE-2026-56403 [4] https://github.com/libexpat/libexpat/pull/1232 Signed-off-by: Deepak Rathore <[email protected]> --- .../expat/expat/CVE-2026-56403_p1.patch | 81 +++++++++++++++++++ .../expat/expat/CVE-2026-56403_p2.patch | 52 ++++++++++++ meta/recipes-core/expat/expat_2.6.4.bb | 2 + 3 files changed, 135 insertions(+) create mode 100644 meta/recipes-core/expat/expat/CVE-2026-56403_p1.patch create mode 100644 meta/recipes-core/expat/expat/CVE-2026-56403_p2.patch diff --git a/meta/recipes-core/expat/expat/CVE-2026-56403_p1.patch b/meta/recipes-core/expat/expat/CVE-2026-56403_p1.patch new file mode 100644 index 0000000000..f5e55eb6e3 --- /dev/null +++ b/meta/recipes-core/expat/expat/CVE-2026-56403_p1.patch @@ -0,0 +1,81 @@ +From b689559597116ee75a633453e2f7177c8541b04e Mon Sep 17 00:00:00 2001 +From: Sebastian Pipping <[email protected]> +Date: Wed, 20 May 2026 12:12:10 +0200 +Subject: [PATCH 01/17] lib: Protect function `storeAtts` from signed integer + overflow + +CVE: CVE-2026-56403 +Upstream-Status: Backport [https://github.com/libexpat/libexpat/commit/12dc6d8d3d65f79471a94d8565f6bf1cf245f648] + +Backport Changes: +- Adapt storeAtts to the Scarthgap 2.6.4 loop and URI allocation + logic while preserving the upstream overflow checks. + +(cherry picked from commit 12dc6d8d3d65f79471a94d8565f6bf1cf245f648) +Signed-off-by: Deepak Rathore <[email protected]> +--- + expat/lib/xmlparse.c | 30 ++++++++++++++++++++---------- + 1 file changed, 20 insertions(+), 10 deletions(-) + +diff --git a/expat/lib/xmlparse.c b/expat/lib/xmlparse.c +index 9bc67f38..df92a3ca 100644 +--- a/expat/lib/xmlparse.c ++++ b/expat/lib/xmlparse.c +@@ -4226,26 +4226,32 @@ storeAtts(XML_Parser parser, const ENCODING *enc, const char *attStr, + return XML_ERROR_NONE; + prefixLen = 0; + if (parser->m_ns_triplets && binding->prefix->name) { +- for (; binding->prefix->name[prefixLen++];) +- ; /* prefixLen includes null terminator */ ++ size_t candidateLen = 0; ++ for (; binding->prefix->name[candidateLen++];) ++ ; /* candidateLen includes null terminator */ ++ /* Detect and prevent integer overflow */ ++ if (candidateLen > INT_MAX) ++ return XML_ERROR_NO_MEMORY; ++ prefixLen = (int)candidateLen; + } + tagNamePtr->localPart = localPart; + tagNamePtr->uriLen = binding->uriLen; + tagNamePtr->prefix = binding->prefix->name; + tagNamePtr->prefixLen = prefixLen; +- for (i = 0; localPart[i++];) +- ; /* i includes null terminator */ ++ ++ size_t localPartLen = 0; ++ for (; localPart[localPartLen++];) ++ ; /* localPartLen includes null terminator */ + + /* Detect and prevent integer overflow */ +- if (binding->uriLen > INT_MAX - prefixLen +- || i > INT_MAX - (binding->uriLen + prefixLen)) { ++ if (localPartLen > INT_MAX || binding->uriLen > INT_MAX - prefixLen ++ || localPartLen > (size_t)INT_MAX - (binding->uriLen + prefixLen)) { + return XML_ERROR_NO_MEMORY; + } + +- n = i + binding->uriLen + prefixLen; ++ n = (int)localPartLen + binding->uriLen + prefixLen; + if (n > binding->uriAlloc) { + TAG *p; +- + /* Detect and prevent integer overflow */ + if (n > INT_MAX - EXPAND_SPARE) { + return XML_ERROR_NO_MEMORY; +@@ -4273,10 +4279,14 @@ storeAtts(XML_Parser parser, const ENCODING *enc, const char *attStr, + } + /* if m_namespaceSeparator != '\0' then uri includes it already */ + uri = binding->uri + binding->uriLen; +- memcpy(uri, localPart, i * sizeof(XML_Char)); ++ /* Detect and prevent integer overflow */ ++ if (localPartLen > SIZE_MAX / sizeof(XML_Char)) { ++ return XML_ERROR_NO_MEMORY; ++ } ++ memcpy(uri, localPart, localPartLen * sizeof(XML_Char)); + /* we always have a namespace separator between localPart and prefix */ + if (prefixLen) { +- uri += i - 1; ++ uri += localPartLen - 1; + *uri = parser->m_namespaceSeparator; /* replace null terminator */ + memcpy(uri + 1, binding->prefix->name, prefixLen * sizeof(XML_Char)); + } diff --git a/meta/recipes-core/expat/expat/CVE-2026-56403_p2.patch b/meta/recipes-core/expat/expat/CVE-2026-56403_p2.patch new file mode 100644 index 0000000000..b578cb60cc --- /dev/null +++ b/meta/recipes-core/expat/expat/CVE-2026-56403_p2.patch @@ -0,0 +1,52 @@ +From 2855ce68a1ce9732267c06734427930364ab66c1 Mon Sep 17 00:00:00 2001 +From: Sebastian Pipping <[email protected]> +Date: Fri, 22 May 2026 00:43:52 +0200 +Subject: [PATCH 02/17] xmlwf: Protect function `xcsdup` from signed integer + overflow + +CVE: CVE-2026-56403 +Upstream-Status: Backport [https://github.com/libexpat/libexpat/commit/147c8f36d6277d5c6011c098370a8362aed47b15] + +Backport Changes: +- Add stdint.h and convert count and numBytes to size_t because + Scarthgap 2.6.4 lacks these upstream prerequisites. + +(cherry picked from commit 147c8f36d6277d5c6011c098370a8362aed47b15) +Signed-off-by: Deepak Rathore <[email protected]> +--- + expat/xmlwf/xmlwf.c | 10 ++++++++-- + 1 file changed, 8 insertions(+), 2 deletions(-) + +diff --git a/expat/xmlwf/xmlwf.c b/expat/xmlwf/xmlwf.c +index fd4fc3f8..7bbdb303 100644 +--- a/expat/xmlwf/xmlwf.c ++++ b/expat/xmlwf/xmlwf.c +@@ -45,6 +45,7 @@ + + #include <assert.h> + #include <stdio.h> ++#include <stdint.h> + #include <stdlib.h> + #include <stddef.h> + #include <string.h> +@@ -304,13 +305,18 @@ processingInstruction(void *userData, const XML_Char *target, + static XML_Char * + xcsdup(const XML_Char *s) { + XML_Char *result; +- int count = 0; +- int numBytes; ++ size_t count = 0; ++ size_t numBytes; + + /* Get the length of the string, including terminator */ + while (s[count++] != 0) { + /* Do nothing */ + } ++ ++ // Detect and prevent integer overflow ++ if (count > SIZE_MAX / sizeof(XML_Char)) ++ return NULL; ++ + numBytes = count * sizeof(XML_Char); + result = malloc(numBytes); + if (result == NULL) diff --git a/meta/recipes-core/expat/expat_2.6.4.bb b/meta/recipes-core/expat/expat_2.6.4.bb index 151720a9e3..dba4b2c81d 100644 --- a/meta/recipes-core/expat/expat_2.6.4.bb +++ b/meta/recipes-core/expat/expat_2.6.4.bb @@ -51,6 +51,8 @@ SRC_URI = "${GITHUB_BASE_URI}/download/R_${VERSION_TAG}/expat-${PV}.tar.bz2 \ file://CVE-2026-32777-02.patch \ file://CVE-2026-32778-01.patch \ file://CVE-2026-32778-02.patch \ + file://CVE-2026-56403_p1.patch;striplevel=2 \ + file://CVE-2026-56403_p2.patch;striplevel=2 \ " GITHUB_BASE_URI = "https://github.com/libexpat/libexpat/releases/";
-=-=-=-=-=-=-=-=-=-=-=- Links: You receive all messages sent to this group. View/Reply Online (#241140): https://lists.openembedded.org/g/openembedded-core/message/241140 Mute This Topic: https://lists.openembedded.org/mt/120311079/21656 Group Owner: [email protected] Unsubscribe: https://lists.openembedded.org/g/openembedded-core/unsub [[email protected]] -=-=-=-=-=-=-=-=-=-=-=-
