From patchwork Sat Oct 3 09:50:49 2026 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Peter Marko X-Patchwork-Id: 99917 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from aws-us-west-2-korg-lkml-1.web.codeaurora.org (localhost.localdomain [127.0.0.1]) by smtp.lore.kernel.org (Postfix) with ESMTP id E9B1BCA5FDD for ; Sat, 3 Oct 2026 09:51:44 +0000 (UTC) Received: from mta-64-228.siemens.flowmailer.net (mta-64-228.siemens.flowmailer.net [185.136.64.228]) by mx.groups.io with SMTP id smtpd.msgproc02-g2.2861.1791021095270220593 for ; Sat, 03 Oct 2026 02:51:35 -0700 Authentication-Results: mx.groups.io; dkim=pass header.i=peter.marko@siemens.com header.s=fm1 header.b=fnS4GjxE; spf=pass (domain: rts-flowmailer.siemens.com, ip: 185.136.64.228, mailfrom: fm-256628-20261003095132bce53035d400020770-rbfhec@rts-flowmailer.siemens.com) Received: by mta-64-228.siemens.flowmailer.net with ESMTPSA id 20261003095132bce53035d400020770 for ; Sat, 03 Oct 2026 11:51:32 +0200 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; s=fm1; d=siemens.com; i=peter.marko@siemens.com; h=Date:From:Subject:To:Message-ID:MIME-Version:Content-Type:Content-Transfer-Encoding:Cc:References:In-Reply-To; bh=xq4KWfGKXdWLrmf872sl9MIInF25zg/93oehY1YNsLk=; b=fnS4GjxELaTKvZwj4WF5q17TcLtVLdxnca8Ql3IGPt6pJ9pUS7nscoYwryRHhAqK/MFyQj 4g6z5KxfxzwYVwor1kwNEBamgfiqdEfiCVBUK8FKVUvSh0ucl6GYvK1kaX9iatEin7ZmglbG EQNDbWChS8SEUhTTItQODUru/5QkQSPz5i7RUYmg6j/jkU6MdCIcurIIchE/iEouLkfFfpJR +sS4eZ/aEtSnj9AEhXMKdAyQYNHU9AVDCR7RlRE6yo4Rc+p8ZpMfRAUSJmDmB+G0m+Ml4rvK 8w54Ej9LYXJgoM9BhDnCFyknLqVOy4a/a05kVU8BNgpSoZwdHpTjBRUg==; From: Peter Marko To: openembedded-devel@lists.openembedded.org Cc: Peter Marko Subject: [scarthgap][PATCH 2/2] c-ares: patch CVE-2026-69184 Date: Sat, 3 Oct 2026 11:50:49 +0200 Message-ID: <20261003095050.3977773-2-peter.marko@siemens.com> In-Reply-To: <20261003095050.3977773-1-peter.marko@siemens.com> References: <20261003095050.3977773-1-peter.marko@siemens.com> MIME-Version: 1.0 X-Flowmailer-Platform: Siemens Feedback-ID: 519:519-256628:519-21489:flowmailer List-Id: X-Webhook-Received: from 45-33-107-173.ip.linodeusercontent.com [45.33.107.173] by aws-us-west-2-korg-lkml-1.web.codeaurora.org with HTTPS for ; Sat, 03 Oct 2026 09:51:44 -0000 X-Groupsio-URL: https://lists.openembedded.org/g/openembedded-devel/message/130614 From: Peter Marko Pick patch per [1]. [1] https://security-tracker.debian.org/tracker/CVE-2026-69184 Signed-off-by: Peter Marko --- .../c-ares/c-ares/CVE-2026-69184.patch | 295 ++++++++++++++++++ .../recipes-support/c-ares/c-ares_1.27.0.bb | 1 + 2 files changed, 296 insertions(+) create mode 100644 meta-oe/recipes-support/c-ares/c-ares/CVE-2026-69184.patch diff --git a/meta-oe/recipes-support/c-ares/c-ares/CVE-2026-69184.patch b/meta-oe/recipes-support/c-ares/c-ares/CVE-2026-69184.patch new file mode 100644 index 0000000000..864d45fa63 --- /dev/null +++ b/meta-oe/recipes-support/c-ares/c-ares/CVE-2026-69184.patch @@ -0,0 +1,295 @@ +From 5c8341ba6ff3a8e4e4dfd616f8ed0418838b8b7b Mon Sep 17 00:00:00 2001 +From: "c-ares-backport-gha[bot]" + <299594594+c-ares-backport-gha[bot]@users.noreply.github.com> +Date: Sun, 5 Jul 2026 05:41:49 +0000 +Subject: [PATCH] [Backport v1.34] enforce 255 octet name limit when parsing + dns names (#1210) + +# Description +Backport of #1164 to `v1.34`. + +Signed-off-by: Syed Mohammed Nayyar +Co-authored-by: jmestwa-coder + +CVE: CVE-2026-69184 +Upstream-Status: Backport [https://github.com/c-ares/c-ares/commit/5c8341ba6ff3a8e4e4dfd616f8ed0418838b8b7b] +Signed-off-by: Peter Marko +--- + src/lib/ares_dns_name.c | 42 +++++++++- + test/ares-test-parse.cc | 176 ++++++++++++++++++++++++++++++++++++++++ + 2 files changed, 216 insertions(+), 2 deletions(-) + +diff --git a/src/lib/ares_dns_name.c b/src/lib/ares_dns_name.c +index b7fdf594..134f3edc 100644 +--- a/src/lib/ares_dns_name.c ++++ b/src/lib/ares_dns_name.c +@@ -27,6 +27,18 @@ + #include "ares.h" + #include "ares_private.h" + ++/* RFC 1035 3.1 limits a name to 255 octets. We track presentation length ++ * (label octets plus one separator before each label after the first), which is ++ * up to ~2 octets looser than the strict wire limit and so never rejects a ++ * compliant name. Shared by the read and write paths. */ ++#define ARES_MAX_NAME_PRESENTATION_LEN 255 ++ ++/* A name of <= 255 octets holds at most 128 labels, so it can never legitimately ++ * require more than that many compression-pointer jumps. Bounding the number of ++ * indirections stops a name built purely from pointers (which never adds label ++ * bytes, so the length cap never fires) from being walked without limit. */ ++#define ARES_MAX_INDIRS 128 ++ + typedef struct { + char *name; + size_t name_len; +@@ -50,7 +62,7 @@ static ares_status_t ares__nameoffset_create(ares__llist_t **list, + ares_nameoffset_t *off = NULL; + + if (list == NULL || name == NULL || ares_strlen(name) == 0 || +- ares_strlen(name) > 255) { ++ ares_strlen(name) > ARES_MAX_NAME_PRESENTATION_LEN) { + return ARES_EFORMERR; + } + +@@ -341,7 +353,7 @@ static ares_status_t ares_split_dns_name(ares_dns_labels_t *labels, + } + + /* Can't exceed maximum (unescaped) length */ +- if (labels->num && total_len + labels->num - 1 > 255) { ++ if (labels->num && total_len + labels->num - 1 > ARES_MAX_NAME_PRESENTATION_LEN) { + status = ARES_EBADNAME; + goto done; + } +@@ -541,6 +553,8 @@ ares_status_t ares__dns_name_parse(ares__buf_t *buf, char **name, + ares_status_t status; + ares__buf_t *namebuf = NULL; + size_t label_start = ares__buf_get_position(buf); ++ size_t name_len = 0; ++ size_t indir = 0; + + if (buf == NULL) { + return ARES_EFORMERR; +@@ -612,6 +626,16 @@ ares_status_t ares__dns_name_parse(ares__buf_t *buf, char **name, + goto fail; + } + ++ /* Bound the number of indirections. A name made purely of pointers never ++ * adds label bytes, so the length cap below can't stop it; the ++ * strictly-decreasing rule alone still allows thousands of jumps per name. ++ * No legitimate <= 255 octet name needs more than 128 labels/jumps. */ ++ indir++; ++ if (indir > ARES_MAX_INDIRS) { ++ status = ARES_EBADNAME; ++ goto fail; ++ } ++ + /* First time we make a jump, save the current position */ + if (save_offset == 0) { + save_offset = ares__buf_get_position(buf); +@@ -635,6 +659,20 @@ ares_status_t ares__dns_name_parse(ares__buf_t *buf, char **name, + + /* New label */ + ++ /* RFC 1035 3.1 limits a name to 255 octets. Enforce it during ++ * decompression so labels reached through a chain of pointers can't expand a ++ * single name without bound. Track the presentation length (label data plus ++ * the separator that precedes each label after the first), matching ++ * ares_split_dns_name() on the write side. */ ++ if (name_len) { ++ name_len++; ++ } ++ name_len += c; ++ if (name_len > ARES_MAX_NAME_PRESENTATION_LEN) { ++ status = ARES_EBADNAME; ++ goto fail; ++ } ++ + /* Labels are separated by periods */ + if (ares__buf_len(namebuf) != 0 && name != NULL) { + status = ares__buf_append_byte(namebuf, '.'); +diff --git a/test/ares-test-parse.cc b/test/ares-test-parse.cc +index 81fd7deb..399c94dd 100644 +--- a/test/ares-test-parse.cc ++++ b/test/ares-test-parse.cc +@@ -219,5 +219,181 @@ TEST_F(LibraryTest, ParseMalformedRRCount) { + EXPECT_EQ(nullptr, dnsrec); + } + ++TEST_F(LibraryTest, ParseRejectsOverlongName) { ++ // RFC 1035 3.1 limits a name to 255 octets. A longer name (here built from ++ // six 63-octet labels) must be rejected instead of expanded. ++ std::vector data = { ++ 0x12, 0x34, 0x81, 0x80, ++ 0x00, 0x01, // num questions ++ 0x00, 0x01, // num answer RRs ++ 0x00, 0x00, // num authority RRs ++ 0x00, 0x00, // num additional RRs ++ // Question ++ 0x01, 'a', 0x00, ++ 0x00, 0x01, // type A ++ 0x00, 0x01, // class IN ++ }; ++ // Answer name: 6 x 63 label octets + 5 separators = 383 presentation octets ++ // (> 255), then root terminator ++ for (int i = 0; i < 6; i++) { ++ data.push_back(63); ++ for (int j = 0; j < 63; j++) { ++ data.push_back('a'); ++ } ++ } ++ data.push_back(0x00); ++ std::vector tail = { ++ 0x00, 0x01, // type A ++ 0x00, 0x01, // class IN ++ 0x00, 0x00, 0x00, 0x00, // TTL ++ 0x00, 0x04, // rdata length ++ 0x01, 0x02, 0x03, 0x04, ++ }; ++ data.insert(data.end(), tail.begin(), tail.end()); ++ ++ ares_dns_record_t *dnsrec = NULL; ++ EXPECT_EQ(ARES_EBADNAME, ares_dns_parse(data.data(), data.size(), 0, &dnsrec)); ++ EXPECT_EQ(nullptr, dnsrec); ++} ++ ++TEST_F(LibraryTest, ParseRejectsOverlongNameViaPointers) { ++ // The answer name is one 63-octet label followed by a compression pointer back ++ // to the question name (four 63-octet labels). Expanded that is 5 x 63 label ++ // octets + 4 separators = 319 presentation octets (> 255), so the length has ++ // to accumulate across the pointer jump for this to be rejected. ++ std::vector data = { ++ 0x12, 0x34, 0x81, 0x80, ++ 0x00, 0x01, // num questions ++ 0x00, 0x01, // num answer RRs ++ 0x00, 0x00, // num authority RRs ++ 0x00, 0x00, // num additional RRs ++ }; ++ // Question name: 4 x 63 label octets + 3 separators = 255 presentation octets, ++ // exactly the limit, so the question itself is accepted. ++ for (int i = 0; i < 4; i++) { ++ data.push_back(63); ++ for (int j = 0; j < 63; j++) { ++ data.push_back('a'); ++ } ++ } ++ data.push_back(0x00); ++ std::vector qtail = {0x00, 0x01, 0x00, 0x01}; // type A, class IN ++ data.insert(data.end(), qtail.begin(), qtail.end()); ++ // Answer name: one 63-octet label, then a pointer to the question name. ++ data.push_back(63); ++ for (int j = 0; j < 63; j++) { ++ data.push_back('a'); ++ } ++ data.push_back(0xc0); ++ data.push_back(0x0c); // -> offset 12, start of question name ++ std::vector tail = { ++ 0x00, 0x01, 0x00, 0x01, 0x00, 0x00, 0x00, 0x00, 0x00, 0x04, 1, 2, 3, 4, ++ }; ++ data.insert(data.end(), tail.begin(), tail.end()); ++ ares_dns_record_t *dnsrec = NULL; ++ EXPECT_EQ(ARES_EBADNAME, ares_dns_parse(data.data(), data.size(), 0, &dnsrec)); ++ EXPECT_EQ(nullptr, dnsrec); ++} ++ ++TEST_F(LibraryTest, ParseRejectsPointerChain) { ++ // A name built purely from compression pointers adds no label octets, so the ++ // length cap alone can never stop it. A long backward chain of pointers is ++ // hidden in the opaque rdata of a raw RR, and a second RR's name points at the ++ // top of the chain; walking it must trip the indirection cap and return ++ // EBADNAME rather than following every jump. ++ std::vector data = { ++ 0x12, 0x34, 0x81, 0x80, ++ 0x00, 0x01, // num questions ++ 0x00, 0x02, // num answer RRs ++ 0x00, 0x00, // num authority RRs ++ 0x00, 0x00, // num additional RRs ++ // Question ++ 0x01, 'a', 0x00, ++ 0x00, 0x01, // type A ++ 0x00, 0x01, // class IN ++ // RR1: raw RR (unknown type) whose rdata carries the pointer chain ++ 0x00, // name = root ++ 0xff, 0xfe, // type (unknown -> stored raw, rdata not name-parsed) ++ 0x00, 0x01, // class IN ++ 0x00, 0x00, 0x00, 0x00, // TTL ++ }; ++ // The chain lives in RR1's rdata, which begins two octets past here (after the ++ // rdlength we are about to write), so compute absolute offsets from there. ++ const size_t rdata_off = data.size() + 2; ++ std::vector chain; ++ chain.push_back(0x00); // deepest target: root terminator ++ size_t prev = rdata_off; // absolute offset of the root ++ size_t top = prev; ++ const int N = 200; // well past the 128 indirection cap ++ for (int i = 0; i < N; i++) { ++ size_t here = rdata_off + chain.size(); ++ chain.push_back(0xc0 | ((prev >> 8) & 0x3f)); ++ chain.push_back(prev & 0xff); ++ top = here; ++ prev = here; ++ } ++ data.push_back((chain.size() >> 8) & 0xff); // rdlength ++ data.push_back(chain.size() & 0xff); ++ data.insert(data.end(), chain.begin(), chain.end()); ++ // RR2: name = pointer to the top of the chain. ++ data.push_back(0xc0 | ((top >> 8) & 0x3f)); ++ data.push_back(top & 0xff); ++ std::vector tail = { ++ 0x00, 0x01, 0x00, 0x01, 0x00, 0x00, 0x00, 0x00, 0x00, 0x04, 1, 2, 3, 4, ++ }; ++ data.insert(data.end(), tail.begin(), tail.end()); ++ ++ ares_dns_record_t *dnsrec = NULL; ++ EXPECT_EQ(ARES_EBADNAME, ares_dns_parse(data.data(), data.size(), 0, &dnsrec)); ++ EXPECT_EQ(nullptr, dnsrec); ++} ++ ++TEST_F(LibraryTest, ParseAcceptsMaxLengthName) { ++ // Exactly 255 presentation octets: 4 x 63 = 252 + 3 separators = 255, which ++ // must still be accepted (the bound is "> 255", not ">= 255"). ++ std::vector data = { ++ 0x12, 0x34, 0x81, 0x80, 0x00, 0x01, 0x00, 0x01, 0x00, 0x00, ++ 0x00, 0x00, 0x01, 'a', 0x00, 0x00, 0x01, 0x00, 0x01, ++ }; ++ for (int i = 0; i < 4; i++) { ++ data.push_back(63); ++ for (int j = 0; j < 63; j++) { ++ data.push_back('a'); ++ } ++ } ++ data.push_back(0x00); ++ std::vector tail = { ++ 0x00, 0x01, 0x00, 0x01, 0x00, 0x00, 0x00, 0x00, 0x00, 0x04, 1, 2, 3, 4, ++ }; ++ data.insert(data.end(), tail.begin(), tail.end()); ++ ares_dns_record_t *dnsrec = NULL; ++ EXPECT_EQ(ARES_SUCCESS, ares_dns_parse(data.data(), data.size(), 0, &dnsrec)); ++ EXPECT_NE(nullptr, dnsrec); ++ ares_dns_record_destroy(dnsrec); ++} ++ ++TEST_F(LibraryTest, ParseRejectsName256) { ++ // One octet over: labels 63,63,63,62,1 = 252 + 4 separators = 256 -> reject. ++ std::vector data = { ++ 0x12, 0x34, 0x81, 0x80, 0x00, 0x01, 0x00, 0x01, 0x00, 0x00, ++ 0x00, 0x00, 0x01, 'a', 0x00, 0x00, 0x01, 0x00, 0x01, ++ }; ++ const int lens[] = {63, 63, 63, 62, 1}; ++ for (int i = 0; i < 5; i++) { ++ data.push_back(static_cast(lens[i])); ++ for (int j = 0; j < lens[i]; j++) { ++ data.push_back('a'); ++ } ++ } ++ data.push_back(0x00); ++ std::vector tail = { ++ 0x00, 0x01, 0x00, 0x01, 0x00, 0x00, 0x00, 0x00, 0x00, 0x04, 1, 2, 3, 4, ++ }; ++ data.insert(data.end(), tail.begin(), tail.end()); ++ ares_dns_record_t *dnsrec = NULL; ++ EXPECT_EQ(ARES_EBADNAME, ares_dns_parse(data.data(), data.size(), 0, &dnsrec)); ++ EXPECT_EQ(nullptr, dnsrec); ++} ++ + } // namespace test + } // namespace ares diff --git a/meta-oe/recipes-support/c-ares/c-ares_1.27.0.bb b/meta-oe/recipes-support/c-ares/c-ares_1.27.0.bb index f409899026..3fb5a35311 100644 --- a/meta-oe/recipes-support/c-ares/c-ares_1.27.0.bb +++ b/meta-oe/recipes-support/c-ares/c-ares_1.27.0.bb @@ -8,6 +8,7 @@ LIC_FILES_CHKSUM = "file://LICENSE.md;md5=fdbc58a6da11a9f68aa73c453818decc" SRC_URI = "https://github.com/c-ares/c-ares/releases/download/cares-1_27_0/${BPN}-${PV}.tar.gz \ file://run-ptest \ file://CVE-2026-69186.patch \ + file://CVE-2026-69184.patch \ " SRC_URI[sha256sum] = "0a72be66959955c43e2af2fbd03418e82a2bd5464604ec9a62147e37aceb420b"