path: root/src/eap_peer/eap_pwd.c
diff options
authorJouni Malinen <j@w1.fi>2015-11-01 16:18:17 (GMT)
committerJouni Malinen <j@w1.fi>2015-11-10 16:40:54 (GMT)
commit8057821706784608b828e769ccefbced95591e50 (patch)
tree16e6391c0b4cf2de36a66761d6544187deb51481 /src/eap_peer/eap_pwd.c
parent03ed0a52393710be6bdae657d1b36efa146520e5 (diff)
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>
Diffstat (limited to 'src/eap_peer/eap_pwd.c')
1 files 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_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;