Commit bcf98fe6 authored by Gustavo Zacarias's avatar Gustavo Zacarias Committed by Thomas Petazzoni
Browse files

hostapd: add security patches 



Fixes:
CVE-2015-5314 - hostapd: EAP-pwd missing last fragment length validation

Signed-off-by: default avatarGustavo Zacarias <gustavo@zacarias.com.ar>
Signed-off-by: default avatarThomas Petazzoni <thomas.petazzoni@free-electrons.com>
parent 76db6b0d

package/hostapd/0001-EAP-pwd-peer-Fix-last-fragment-length-validation.patch

0 → 100644
+54 −0
Original line number Diff line number Diff line 
From 8057821706784608b828e769ccefbced95591e50 Mon Sep 17 00:00:00 2001

From: Jouni Malinen <j@w1.fi>

Date: Sun, 1 Nov 2015 18:18:17 +0200

Subject: [PATCH] EAP-pwd peer: Fix last fragment length validation



All but the last fragment had their length checked against the remaining

room in the reassembly buffer. This allowed a suitably constructed last

fragment frame to try to add extra data that would go beyond the buffer.

The length validation code in wpabuf_put_data() prevents an actual

buffer write overflow from occurring, but this results in process

termination. (CVE-2015-5315)



Signed-off-by: Jouni Malinen <j@w1.fi>

---

 src/eap_peer/eap_pwd.c | 7 +++----

 1 file changed, 3 insertions(+), 4 deletions(-)



diff --git a/src/eap_peer/eap_pwd.c b/src/eap_peer/eap_pwd.c

index 1f78544..75ceef1 100644

--- a/src/eap_peer/eap_pwd.c

+++ b/src/eap_peer/eap_pwd.c

@@ -903,7 +903,7 @@ eap_pwd_process(struct eap_sm *sm, void *priv, struct eap_method_ret *ret,

 	/*

 	 * buffer and ACK the fragment

 	 */

-	if (EAP_PWD_GET_MORE_BIT(lm_exch)) {

+	if (EAP_PWD_GET_MORE_BIT(lm_exch) || data->in_frag_pos) {

 		data->in_frag_pos += len;

 		if (data->in_frag_pos > wpabuf_size(data->inbuf)) {

 			wpa_printf(MSG_INFO, "EAP-pwd: Buffer overflow attack "

@@ -916,7 +916,8 @@ eap_pwd_process(struct eap_sm *sm, void *priv, struct eap_method_ret *ret,

 			return NULL;

 		}

 		wpabuf_put_data(data->inbuf, pos, len);

-

+	}

+	if (EAP_PWD_GET_MORE_BIT(lm_exch)) {

 		resp = eap_msg_alloc(EAP_VENDOR_IETF, EAP_TYPE_PWD,

 				     EAP_PWD_HDR_SIZE,

 				     EAP_CODE_RESPONSE, eap_get_id(reqData));

@@ -930,10 +931,8 @@ eap_pwd_process(struct eap_sm *sm, void *priv, struct eap_method_ret *ret,

 	 * we're buffering and this is the last fragment

 	 */

 	if (data->in_frag_pos) {

-		wpabuf_put_data(data->inbuf, pos, len);

 		wpa_printf(MSG_DEBUG, "EAP-pwd: Last fragment, %d bytes",

 			   (int) len);

-		data->in_frag_pos += len;

 		pos = wpabuf_head_u8(data->inbuf);

 		len = data->in_frag_pos;

 	}

-- 

1.9.1

package/hostapd/0002-EAP-pwd-server-Fix-last-fragment-length-validation.patch

0 → 100644
+51 −0
Original line number Diff line number Diff line 
From bef802ece03f9ae9d52a21f0cf4f1bc2c5a1f8aa Mon Sep 17 00:00:00 2001

From: Jouni Malinen <j@w1.fi>

Date: Sun, 1 Nov 2015 18:24:16 +0200

Subject: [PATCH] EAP-pwd server: Fix last fragment length validation



All but the last fragment had their length checked against the remaining

room in the reassembly buffer. This allowed a suitably constructed last

fragment frame to try to add extra data that would go beyond the buffer.

The length validation code in wpabuf_put_data() prevents an actual

buffer write overflow from occurring, but this results in process

termination. (CVE-2015-5314)



Signed-off-by: Jouni Malinen <j@w1.fi>

---

 src/eap_server/eap_server_pwd.c | 6 +++---

 1 file changed, 3 insertions(+), 3 deletions(-)



diff --git a/src/eap_server/eap_server_pwd.c b/src/eap_server/eap_server_pwd.c

index cb83ff7..9f787ab 100644

--- a/src/eap_server/eap_server_pwd.c

+++ b/src/eap_server/eap_server_pwd.c

@@ -970,7 +970,7 @@ static void eap_pwd_process(struct eap_sm *sm, void *priv,

 	/*

 	 * the first and all intermediate fragments have the M bit set

 	 */

-	if (EAP_PWD_GET_MORE_BIT(lm_exch)) {

+	if (EAP_PWD_GET_MORE_BIT(lm_exch) || data->in_frag_pos) {

 		if ((data->in_frag_pos + len) > wpabuf_size(data->inbuf)) {

 			wpa_printf(MSG_DEBUG, "EAP-pwd: Buffer overflow "

 				   "attack detected! (%d+%d > %d)",

@@ -981,6 +981,8 @@ static void eap_pwd_process(struct eap_sm *sm, void *priv,

 		}

 		wpabuf_put_data(data->inbuf, pos, len);

 		data->in_frag_pos += len;

+	}

+	if (EAP_PWD_GET_MORE_BIT(lm_exch)) {

 		wpa_printf(MSG_DEBUG, "EAP-pwd: Got a %d byte fragment",

 			   (int) len);

 		return;

@@ -990,8 +992,6 @@ static void eap_pwd_process(struct eap_sm *sm, void *priv,

 	 * buffering fragments so that's how we know it's the last)

 	 */

 	if (data->in_frag_pos) {

-		wpabuf_put_data(data->inbuf, pos, len);

-		data->in_frag_pos += len;

 		pos = wpabuf_head_u8(data->inbuf);

 		len = data->in_frag_pos;

 		wpa_printf(MSG_DEBUG, "EAP-pwd: Last fragment, %d bytes",

-- 

1.9.1