[OE-core][whinlatter][PATCH 2/3] avahi: patch CVE-2026-24401

[ankur.tyagi85@gmail.com]

From: Ankur Tyagi <ankur.tyagi85@gmail.com>

Details https://nvd.nist.gov/vuln/detail/CVE-2026-24401

Signed-off-by: Ankur Tyagi <ankur.tyagi85@gmail.com>
---
 meta/recipes-connectivity/avahi/avahi_0.8.bb  |  1 +
 .../avahi/files/CVE-2026-24401.patch          | 74 +++++++++++++++++++
 2 files changed, 75 insertions(+)
 create mode 100644 meta/recipes-connectivity/avahi/files/CVE-2026-24401.patch

diff --git a/meta/recipes-connectivity/avahi/avahi_0.8.bb b/meta/recipes-connectivity/avahi/avahi_0.8.bb
index bd61c39dbf..35f779c914 100644
--- a/meta/recipes-connectivity/avahi/avahi_0.8.bb
+++ b/meta/recipes-connectivity/avahi/avahi_0.8.bb
@@ -38,6 +38,7 @@ SRC_URI = "${GITHUB_BASE_URI}/download/v${PV}/avahi-${PV}.tar.gz \
            file://CVE-2024-52616.patch \
            file://CVE-2024-52615.patch \
            file://CVE-2025-68276.patch \
+           file://CVE-2026-24401.patch \
            "
 
 GITHUB_BASE_URI = "https://github.com/avahi/avahi/releases/"
diff --git a/meta/recipes-connectivity/avahi/files/CVE-2026-24401.patch b/meta/recipes-connectivity/avahi/files/CVE-2026-24401.patch
new file mode 100644
index 0000000000..1a442966fc
--- /dev/null
+++ b/meta/recipes-connectivity/avahi/files/CVE-2026-24401.patch
@@ -0,0 +1,74 @@
+From 5eea2640324928c15936b7a2bcbf8ea0de7b08f7 Mon Sep 17 00:00:00 2001
+From: Hugo Muis <198191869+friendlyhugo@users.noreply.github.com>
+Date: Sun, 2 Mar 2025 18:06:24 +0100
+Subject: [PATCH] core: fix uncontrolled recursion bug using a simple loop
+ detection algorithm
+
+Closes https://github.com/avahi/avahi/issues/501
+
+CVE: CVE-2026-24401
+Upstream-Status: Backport [https://github.com/avahi/avahi/commit/78eab31128479f06e30beb8c1cbf99dd921e2524]
+(cherry picked from commit 78eab31128479f06e30beb8c1cbf99dd921e2524)
+Signed-off-by: Ankur Tyagi <ankur.tyagi85@gmail.com>
+---
+ avahi-core/browse.c | 40 ++++++++++++++++++++++++++++++++++++++++
+ 1 file changed, 40 insertions(+)
+
+diff --git a/avahi-core/browse.c b/avahi-core/browse.c
+index f461083..975b3e9 100644
+--- a/avahi-core/browse.c
++++ b/avahi-core/browse.c
+@@ -401,6 +401,40 @@ static int lookup_go(AvahiSRBLookup *l) {
+     return n;
+ }
+ 
++static int lookup_exists_in_path(AvahiSRBLookup* lookup, AvahiSRBLookup* from, AvahiSRBLookup* to) {
++    AvahiRList* rl;
++    if (from == to)
++        return 0;
++    for (rl = from->cname_lookups; rl; rl = rl->rlist_next) {
++        int r = lookup_exists_in_path(lookup, rl->data, to);
++        if (r == 1) {
++            /* loop detected, propagate result */
++            return r;
++        } else if (r == 0) {
++            /* is loop detected? */
++            return lookup == from;
++        } else {
++	        /* `to` not found, continue */
++            continue;
++        }
++    }
++    /* no path found */
++    return -1;
++}
++
++static int cname_would_create_loop(AvahiSRBLookup* l, AvahiSRBLookup* n) {
++    int ret;
++    if (l == n)
++        /* Loop to self */
++        return 1;
++
++    ret = lookup_exists_in_path(n, l->record_browser->root_lookup, l);
++
++    /* Path to n always exists */
++    assert(ret != -1);
++    return ret;
++}
++
+ static void lookup_handle_cname(AvahiSRBLookup *l, AvahiIfIndex interface, AvahiProtocol protocol, AvahiLookupFlags flags, AvahiRecord *r) {
+     AvahiKey *k;
+     AvahiSRBLookup *n;
+@@ -420,6 +454,12 @@ static void lookup_handle_cname(AvahiSRBLookup *l, AvahiIfIndex interface, Avahi
+         return;
+     }
+ 
++    if (cname_would_create_loop(l, n)) {
++        /* CNAME loops are not allowed */
++        lookup_unref(n);
++        return;
++    }
++
+     l->cname_lookups = avahi_rlist_prepend(l->cname_lookups, lookup_ref(n));
+ 
+     lookup_go(n);