wpa-supplicant: Security fix CVE-2020-12695

Source: http://w1.fi/security/
Disposition: Backport from http://w1.fi/security/2020-1/

Affects <= 2.9 wpa-supplicant

(From OE-Core rev: e9c696397ae1b4344b8329a13076f265980ee74d)

Signed-off-by: Armin Kuster <akuster@mvista.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

4 files changed, 267 insertions, 1 deletions

diff --git a/meta/recipes-connectivity/wpa-supplicant/wpa-supplicant/0001-WPS-UPnP-Do-not-allow-event-subscriptions-with-URLs-.patch b/meta/recipes-connectivity/wpa-supplicant/wpa-supplicant/0001-WPS-UPnP-Do-not-allow-event-subscriptions-with-URLs-.patch
new file mode 100644
index 0000000000..53ad5d028a
--- /dev/null
+++ b/meta/recipes-connectivity/wpa-supplicant/wpa-supplicant/0001-WPS-UPnP-Do-not-allow-event-subscriptions-with-URLs-.patch
@@ -0,0 +1,151 @@
+From 5b78c8f961f25f4dc22d6f2b77ddd06d712cec63 Mon Sep 17 00:00:00 2001
+From: Jouni Malinen <jouni@codeaurora.org>
+Date: Wed, 3 Jun 2020 23:17:35 +0300
+Subject: [PATCH 1/3] WPS UPnP: Do not allow event subscriptions with URLs to
+ other networks
+
+The UPnP Device Architecture 2.0 specification errata ("UDA errata
+16-04-2020.docx") addresses a problem with notifications being allowed
+to go out to other domains by disallowing such cases. Do such filtering
+for the notification callback URLs to avoid undesired connections to
+external networks based on subscriptions that any device in the local
+network could request when WPS support for external registrars is
+enabled (the upnp_iface parameter in hostapd configuration).
+
+Upstream-Status: Backport
+CVE: CVE-2020-12695 patch #1
+Signed-off-by: Jouni Malinen <jouni@codeaurora.org>
+Signed-off-by: Armin Kuster <akuster@mvista.com>
+
+---
+ src/wps/wps_er.c     |  2 +-
+ src/wps/wps_upnp.c   | 38 ++++++++++++++++++++++++++++++++++++--
+ src/wps/wps_upnp_i.h |  3 ++-
+ 3 files changed, 39 insertions(+), 4 deletions(-)
+
+Index: wpa_supplicant-2.9/src/wps/wps_er.c
+===================================================================
+--- wpa_supplicant-2.9.orig/src/wps/wps_er.c
++++ wpa_supplicant-2.9/src/wps/wps_er.c
+@@ -1298,7 +1298,7 @@ wps_er_init(struct wps_context *wps, con
+                           "with %s", filter);
+        }
+        if (get_netif_info(er->ifname, &er->ip_addr, &er->ip_addr_text,
+-                          er->mac_addr)) {
++                          NULL, er->mac_addr)) {
+                wpa_printf(MSG_INFO, "WPS UPnP: Could not get IP/MAC address "
+                           "for %s. Does it have IP address?", er->ifname);
+                wps_er_deinit(er, NULL, NULL);
+Index: wpa_supplicant-2.9/src/wps/wps_upnp.c
+===================================================================
+--- wpa_supplicant-2.9.orig/src/wps/wps_upnp.c
++++ wpa_supplicant-2.9/src/wps/wps_upnp.c
+@@ -303,6 +303,14 @@ static void subscr_addr_free_all(struct
+ }
+
+
++static int local_network_addr(struct upnp_wps_device_sm *sm,
++                             struct sockaddr_in *addr)
++{
++       return (addr->sin_addr.s_addr & sm->netmask.s_addr) ==
++               (sm->ip_addr & sm->netmask.s_addr);
++}
++
++
+ /* subscr_addr_add_url -- add address(es) for one url to subscription */
+ static void subscr_addr_add_url(struct subscription *s, const char *url,
+                                size_t url_len)
+@@ -381,6 +389,7 @@ static void subscr_addr_add_url(struct s
+
+        for (rp = result; rp; rp = rp->ai_next) {
+                struct subscr_addr *a;
++               struct sockaddr_in *addr = (struct sockaddr_in *) rp->ai_addr;
+
+                /* Limit no. of address to avoid denial of service attack */
+                if (dl_list_len(&s->addr_list) >= MAX_ADDR_PER_SUBSCRIPTION) {
+@@ -389,6 +398,13 @@ static void subscr_addr_add_url(struct s
+                        break;
+                }
+
++               if (!local_network_addr(s->sm, addr)) {
++                       wpa_printf(MSG_INFO,
++                                  "WPS UPnP: Ignore a delivery URL that points to another network %s",
++                                  inet_ntoa(addr->sin_addr));
++                       continue;
++               }
++
+                a = os_zalloc(sizeof(*a) + alloc_len);
+                if (a == NULL)
+                        break;
+@@ -889,11 +905,12 @@ static int eth_get(const char *device, u
+  * @net_if: Selected network interface name
+  * @ip_addr: Buffer for returning IP address in network byte order
+  * @ip_addr_text: Buffer for returning a pointer to allocated IP address text
++ * @netmask: Buffer for returning netmask or %NULL if not needed
+  * @mac: Buffer for returning MAC address
+  * Returns: 0 on success, -1 on failure
+  */
+ int get_netif_info(const char *net_if, unsigned *ip_addr, char **ip_addr_text,
+-                  u8 mac[ETH_ALEN])
++                  struct in_addr *netmask, u8 mac[ETH_ALEN])
+ {
+        struct ifreq req;
+        int sock = -1;
+@@ -919,6 +936,19 @@ int get_netif_info(const char *net_if, u
+        in_addr.s_addr = *ip_addr;
+        os_snprintf(*ip_addr_text, 16, "%s", inet_ntoa(in_addr));
+
++       if (netmask) {
++               os_memset(&req, 0, sizeof(req));
++               os_strlcpy(req.ifr_name, net_if, sizeof(req.ifr_name));
++               if (ioctl(sock, SIOCGIFNETMASK, &req) < 0) {
++                       wpa_printf(MSG_ERROR,
++                                  "WPS UPnP: SIOCGIFNETMASK failed: %d (%s)",
++                                  errno, strerror(errno));
++                       goto fail;
++               }
++               addr = (struct sockaddr_in *) &req.ifr_netmask;
++               netmask->s_addr = addr->sin_addr.s_addr;
++       }
++
+ #ifdef __linux__
+        os_strlcpy(req.ifr_name, net_if, sizeof(req.ifr_name));
+        if (ioctl(sock, SIOCGIFHWADDR, &req) < 0) {
+@@ -1025,11 +1055,15 @@ static int upnp_wps_device_start(struct
+
+        /* Determine which IP and mac address we're using */
+        if (get_netif_info(net_if, &sm->ip_addr, &sm->ip_addr_text,
+-                          sm->mac_addr)) {
++                          &sm->netmask, sm->mac_addr)) {
+                wpa_printf(MSG_INFO, "WPS UPnP: Could not get IP/MAC address "
+                           "for %s. Does it have IP address?", net_if);
+                goto fail;
+        }
++       wpa_printf(MSG_DEBUG, "WPS UPnP: Local IP address %s netmask %s hwaddr "
++                  MACSTR,
++                  sm->ip_addr_text, inet_ntoa(sm->netmask),
++                  MAC2STR(sm->mac_addr));
+
+        /* Listen for incoming TCP connections so that others
+         * can fetch our "xml files" from us.
+Index: wpa_supplicant-2.9/src/wps/wps_upnp_i.h
+===================================================================
+--- wpa_supplicant-2.9.orig/src/wps/wps_upnp_i.h
++++ wpa_supplicant-2.9/src/wps/wps_upnp_i.h
+@@ -128,6 +128,7 @@ struct upnp_wps_device_sm {
+        u8 mac_addr[ETH_ALEN]; /* mac addr of network i.f. we use */
+        char *ip_addr_text; /* IP address of network i.f. we use */
+        unsigned ip_addr; /* IP address of network i.f. we use (host order) */
++       struct in_addr netmask;
+        int multicast_sd; /* send multicast messages over this socket */
+        int ssdp_sd; /* receive discovery UPD packets on socket */
+        int ssdp_sd_registered; /* nonzero if we must unregister */
+@@ -158,7 +159,7 @@ struct subscription * subscription_find(
+                                        const u8 uuid[UUID_LEN]);
+ void subscr_addr_delete(struct subscr_addr *a);
+ int get_netif_info(const char *net_if, unsigned *ip_addr, char **ip_addr_text,
+-                  u8 mac[ETH_ALEN]);
++                  struct in_addr *netmask, u8 mac[ETH_ALEN]);
+
+ /* wps_upnp_ssdp.c */
+ void msearchreply_state_machine_stop(struct advertisement_state_machine *a);
diff --git a/meta/recipes-connectivity/wpa-supplicant/wpa-supplicant/0002-WPS-UPnP-Fix-event-message-generation-using-a-long-U.patch b/meta/recipes-connectivity/wpa-supplicant/wpa-supplicant/0002-WPS-UPnP-Fix-event-message-generation-using-a-long-U.patch
new file mode 100644
index 0000000000..59640859dd
--- /dev/null
+++ b/meta/recipes-connectivity/wpa-supplicant/wpa-supplicant/0002-WPS-UPnP-Fix-event-message-generation-using-a-long-U.patch
@@ -0,0 +1,62 @@
+From f7d268864a2660b7239b9a8ff5ad37faeeb751ba Mon Sep 17 00:00:00 2001
+From: Jouni Malinen <jouni@codeaurora.org>
+Date: Wed, 3 Jun 2020 22:41:02 +0300
+Subject: [PATCH 2/3] WPS UPnP: Fix event message generation using a long URL
+ path
+
+More than about 700 character URL ended up overflowing the wpabuf used
+for building the event notification and this resulted in the wpabuf
+buffer overflow checks terminating the hostapd process. Fix this by
+allocating the buffer to be large enough to contain the full URL path.
+However, since that around 700 character limit has been the practical
+limit for more than ten years, start explicitly enforcing that as the
+limit or the callback URLs since any longer ones had not worked before
+and there is no need to enable them now either.
+
+Upstream-Status: Backport
+CVE: CVE-2020-12695 patch #2
+Signed-off-by: Jouni Malinen <jouni@codeaurora.org>
+Signed-off-by: Armin Kuster <akuster@mvista.com>
+
+---
+ src/wps/wps_upnp.c       | 9 +++++++--
+ src/wps/wps_upnp_event.c | 3 ++-
+ 2 files changed, 9 insertions(+), 3 deletions(-)
+
+diff --git a/src/wps/wps_upnp.c b/src/wps/wps_upnp.c
+index 7d4b7439940e..ab685d52ecab 100644
+--- a/src/wps/wps_upnp.c
++++ b/src/wps/wps_upnp.c
+@@ -328,9 +328,14 @@ static void subscr_addr_add_url(struct subscription *s, const char *url,
+        int rerr;
+        size_t host_len, path_len;
+
+-       /* url MUST begin with http: */
+-       if (url_len < 7 || os_strncasecmp(url, "http://", 7))
++       /* URL MUST begin with HTTP scheme. In addition, limit the length of
++        * the URL to 700 characters which is around the limit that was
++        * implicitly enforced for more than 10 years due to a bug in
++        * generating the event messages. */
++       if (url_len < 7 || os_strncasecmp(url, "http://", 7) || url_len > 700) {
++               wpa_printf(MSG_DEBUG, "WPS UPnP: Reject an unacceptable URL");
+                goto fail;
++       }
+        url += 7;
+        url_len -= 7;
+
+diff --git a/src/wps/wps_upnp_event.c b/src/wps/wps_upnp_event.c
+index d7e6edcc6503..08a23612f338 100644
+--- a/src/wps/wps_upnp_event.c
++++ b/src/wps/wps_upnp_event.c
+@@ -147,7 +147,8 @@ static struct wpabuf * event_build_message(struct wps_event_ *e)
+        struct wpabuf *buf;
+        char *b;
+
+-       buf = wpabuf_alloc(1000 + wpabuf_len(e->data));
++       buf = wpabuf_alloc(1000 + os_strlen(e->addr->path) +
++                          wpabuf_len(e->data));
+        if (buf == NULL)
+                return NULL;
+        wpabuf_printf(buf, "NOTIFY %s HTTP/1.1\r\n", e->addr->path);
+--
+2.20.1
diff --git a/meta/recipes-connectivity/wpa-supplicant/wpa-supplicant/0003-WPS-UPnP-Handle-HTTP-initiation-failures-for-events-.patch b/meta/recipes-connectivity/wpa-supplicant/wpa-supplicant/0003-WPS-UPnP-Handle-HTTP-initiation-failures-for-events-.patch
new file mode 100644
index 0000000000..8a014ef28a
--- /dev/null
+++ b/meta/recipes-connectivity/wpa-supplicant/wpa-supplicant/0003-WPS-UPnP-Handle-HTTP-initiation-failures-for-events-.patch
@@ -0,0 +1,50 @@
+From 85aac526af8612c21b3117dadc8ef5944985b476 Mon Sep 17 00:00:00 2001
+From: Jouni Malinen <jouni@codeaurora.org>
+Date: Thu, 4 Jun 2020 21:24:04 +0300
+Subject: [PATCH 3/3] WPS UPnP: Handle HTTP initiation failures for events more
+ properly
+
+While it is appropriate to try to retransmit the event to another
+callback URL on a failure to initiate the HTTP client connection, there
+is no point in trying the exact same operation multiple times in a row.
+Replve the event_retry() calls with event_addr_failure() for these cases
+to avoid busy loops trying to repeat the same failing operation.
+
+These potential busy loops would go through eloop callbacks, so the
+process is not completely stuck on handling them, but unnecessary CPU
+would be used to process the continues retries that will keep failing
+for the same reason.
+
+Upstream-Status: Backport
+CVE: CVE-2020-12695 patch #2
+Signed-off-by: Jouni Malinen <jouni@codeaurora.org>
+Signed-off-by: Armin Kuster <akuster@mvista.com>
+
+---
+ src/wps/wps_upnp_event.c | 4 ++--
+ 1 file changed, 2 insertions(+), 2 deletions(-)
+
+diff --git a/src/wps/wps_upnp_event.c b/src/wps/wps_upnp_event.c
+index 08a23612f338..c0d9e41d9a38 100644
+--- a/src/wps/wps_upnp_event.c
++++ b/src/wps/wps_upnp_event.c
+@@ -294,7 +294,7 @@ static int event_send_start(struct subscription *s)
+
+        buf = event_build_message(e);
+        if (buf == NULL) {
+-               event_retry(e, 0);
++               event_addr_failure(e);
+                return -1;
+        }
+
+@@ -302,7 +302,7 @@ static int event_send_start(struct subscription *s)
+                                         event_http_cb, e);
+        if (e->http_event == NULL) {
+                wpabuf_free(buf);
+-               event_retry(e, 0);
++               event_addr_failure(e);
+                return -1;
+        }
+
+--
+2.20.1
diff --git a/meta/recipes-connectivity/wpa-supplicant/wpa-supplicant_2.9.bb b/meta/recipes-connectivity/wpa-supplicant/wpa-supplicant_2.9.bb
index 2936e89eed..7cc03fef7d 100644
--- a/meta/recipes-connectivity/wpa-supplicant/wpa-supplicant_2.9.bb
+++ b/meta/recipes-connectivity/wpa-supplicant/wpa-supplicant_2.9.bb
@@ -25,7 +25,10 @@ SRC_URI = "http://w1.fi/releases/wpa_supplicant-${PV}.tar.gz  \
            file://wpa_supplicant.conf-sane \
            file://99_wpa_supplicant \
            file://0001-replace-systemd-install-Alias-with-WantedBy.patch \
-                   file://0001-AP-Silently-ignore-management-frame-from-unexpected-.patch \
+           file://0001-AP-Silently-ignore-management-frame-from-unexpected-.patch \
+           file://0001-WPS-UPnP-Do-not-allow-event-subscriptions-with-URLs-.patch \
+           file://0002-WPS-UPnP-Fix-event-message-generation-using-a-long-U.patch \
+           file://0003-WPS-UPnP-Handle-HTTP-initiation-failures-for-events-.patch \
           "
 SRC_URI[md5sum] = "2d2958c782576dc9901092fbfecb4190"
 SRC_URI[sha256sum] = "fcbdee7b4a64bea8177973299c8c824419c413ec2e3a95db63dd6a5dc3541f17"