avahi/avahi-CVE-2023-38471.patch
Dominique Leuenberger 13a4ac00ec Accepting request 1162477 from home:xiaoguang_wang:branches:GNOME:Factory
- Add avahi-CVE-2023-38471.patch: Extract host name using
  avahi_unescape_label (bsc#1216594, CVE-2023-38471).
- Add avahi-CVE-2023-38469.patch: Reject overly long TXT resource
  records (bsc#1216598, CVE-2023-38469).

OBS-URL: https://build.opensuse.org/request/show/1162477
OBS-URL: https://build.opensuse.org/package/show/GNOME:Factory/avahi?expand=0&rev=239
2024-03-27 08:21:54 +00:00

72 lines
2.2 KiB
Diff

From 894f085f402e023a98cbb6f5a3d117bd88d93b09 Mon Sep 17 00:00:00 2001
From: Michal Sekletar <msekleta@redhat.com>
Date: Mon, 23 Oct 2023 13:38:35 +0200
Subject: [PATCH] core: extract host name using avahi_unescape_label()
Previously we could create invalid escape sequence when we split the
string on dot. For example, from valid host name "foo\\.bar" we have
created invalid name "foo\\" and tried to set that as the host name
which crashed the daemon.
Fixes #453
CVE-2023-38471
---
avahi-core/server.c | 27 +++++++++++++++++++++------
1 file changed, 21 insertions(+), 6 deletions(-)
diff --git a/avahi-core/server.c b/avahi-core/server.c
index c32637a..f6a21bb 100644
--- a/avahi-core/server.c
+++ b/avahi-core/server.c
@@ -1295,7 +1295,11 @@ static void update_fqdn(AvahiServer *s) {
}
int avahi_server_set_host_name(AvahiServer *s, const char *host_name) {
- char *hn = NULL;
+ char label_escaped[AVAHI_LABEL_MAX*4+1];
+ char label[AVAHI_LABEL_MAX];
+ char *hn = NULL, *h;
+ size_t len;
+
assert(s);
AVAHI_CHECK_VALIDITY(s, !host_name || avahi_is_valid_host_name(host_name), AVAHI_ERR_INVALID_HOST_NAME);
@@ -1305,17 +1309,28 @@ int avahi_server_set_host_name(AvahiServer *s, const char *host_name) {
else
hn = avahi_normalize_name_strdup(host_name);
- hn[strcspn(hn, ".")] = 0;
+ h = hn;
+ if (!avahi_unescape_label((const char **)&hn, label, sizeof(label))) {
+ avahi_free(h);
+ return AVAHI_ERR_INVALID_HOST_NAME;
+ }
+
+ avahi_free(h);
+
+ h = label_escaped;
+ len = sizeof(label_escaped);
+ if (!avahi_escape_label(label, strlen(label), &h, &len))
+ return AVAHI_ERR_INVALID_HOST_NAME;
- if (avahi_domain_equal(s->host_name, hn) && s->state != AVAHI_SERVER_COLLISION) {
- avahi_free(hn);
+ if (avahi_domain_equal(s->host_name, label_escaped) && s->state != AVAHI_SERVER_COLLISION)
return avahi_server_set_errno(s, AVAHI_ERR_NO_CHANGE);
- }
withdraw_host_rrs(s);
avahi_free(s->host_name);
- s->host_name = hn;
+ s->host_name = avahi_strdup(label_escaped);
+ if (!s->host_name)
+ return AVAHI_ERR_NO_MEMORY;
update_fqdn(s);
--
2.44.0