code.ossystems Code Review - openembedded-core.git/blob

   1 Upstream-Status: Backport
   2
   3 Signed-off-by: Fan Xin <fan.xin@jp.fujitsu.com>
   4
   5 From 477c74395acd0123340457ba6f15ab345d42016e Mon Sep 17 00:00:00 2001
   6 From: Jouni Malinen <j@w1.fi>
   7 Date: Sat, 2 May 2015 19:23:04 +0300
   8 Subject: [PATCH 3/5] EAP-pwd peer: Fix Total-Length parsing for fragment
   9  reassembly
  10
  11 The remaining number of bytes in the message could be smaller than the
  12 Total-Length field size, so the length needs to be explicitly checked
  13 prior to reading the field and decrementing the len variable. This could
  14 have resulted in the remaining length becoming negative and interpreted
  15 as a huge positive integer.
  16
  17 In addition, check that there is no already started fragment in progress
  18 before allocating a new buffer for reassembling fragments. This avoid a
  19 potential memory leak when processing invalid message.
  20
  21 Signed-off-by: Jouni Malinen <j@w1.fi>
  22 ---
  23  src/eap_peer/eap_pwd.c | 12 ++++++++++++
  24  1 file changed, 12 insertions(+)
  25
  26 diff --git a/src/eap_peer/eap_pwd.c b/src/eap_peer/eap_pwd.c
  27 index a629437..1d2079b 100644
  28 --- a/src/eap_peer/eap_pwd.c
  29 +++ b/src/eap_peer/eap_pwd.c
  30 @@ -866,11 +866,23 @@ eap_pwd_process(struct eap_sm *sm, void *priv, struct eap_method_ret *ret,
  31          * if it's the first fragment there'll be a length field
  32          */
  33         if (EAP_PWD_GET_LENGTH_BIT(lm_exch)) {
  34 +               if (len < 2) {
  35 +                       wpa_printf(MSG_DEBUG,
  36 +                                  "EAP-pwd: Frame too short to contain Total-Length field");
  37 +                       ret->ignore = TRUE;
  38 +                       return NULL;
  39 +               }
  40                 tot_len = WPA_GET_BE16(pos);
  41                 wpa_printf(MSG_DEBUG, "EAP-pwd: Incoming fragments whose "
  42                            "total length = %d", tot_len);
  43                 if (tot_len > 15000)
  44                         return NULL;
  45 +               if (data->inbuf) {
  46 +                       wpa_printf(MSG_DEBUG,
  47 +                                  "EAP-pwd: Unexpected new fragment start when previous fragment is still in use");
  48 +                       ret->ignore = TRUE;
  49 +                       return NULL;
  50 +               }
  51                 data->inbuf = wpabuf_alloc(tot_len);
  52                 if (data->inbuf == NULL) {
  53                         wpa_printf(MSG_INFO, "Out of memory to buffer "
  54 --
  55 1.9.1
  56