From d2d1a324ce937628e4d9d9999fe113819b7d4478 Mon Sep 17 00:00:00 2001 From: Jouni Malinen Date: Wed, 17 Apr 2019 02:21:20 +0300 Subject: [PATCH 3/3] EAP-pwd peer: Fix reassembly buffer handling Unexpected fragment might result in data->inbuf not being allocated before processing and that could have resulted in NULL pointer dereference. Fix that by explicitly checking for data->inbuf to be available before using it. Signed-off-by: Jouni Malinen --- src/eap_peer/eap_pwd.c | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) diff --git a/src/eap_peer/eap_pwd.c b/src/eap_peer/eap_pwd.c index 46894a5..76fcad4 100644 --- a/src/eap_peer/eap_pwd.c +++ b/src/eap_peer/eap_pwd.c @@ -932,6 +932,13 @@ 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) || data->in_frag_pos) { + if (!data->inbuf) { + wpa_printf(MSG_DEBUG, + "EAP-pwd: No buffer for reassembly"); + ret->methodState = METHOD_DONE; + ret->decision = DECISION_FAIL; + return NULL; + } data->in_frag_pos += len; if (data->in_frag_pos > wpabuf_size(data->inbuf)) { wpa_printf(MSG_INFO, "EAP-pwd: Buffer overflow attack " @@ -958,7 +965,7 @@ 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) { + if (data->in_frag_pos && data->inbuf) { wpa_printf(MSG_DEBUG, "EAP-pwd: Last fragment, %d bytes", (int) len); pos = wpabuf_head_u8(data->inbuf); -- 2.7.4