hostapd: fix post v2.4 security issues

- WPS: Fix HTTP chunked transfer encoding parser (CVE-2015-4141)
- EAP-pwd peer: Fix payload length validation for Commit and Confirm
  (CVE-2015-4143)
- EAP-pwd server: Fix payload length validation for Commit and Confirm
  (CVE-2015-4143)
- EAP-pwd peer: Fix Total-Length parsing for fragment reassembly
  (CVE-2015-4144, CVE-2015-4145)
- EAP-pwd server: Fix Total-Length parsing for fragment reassembly
  (CVE-2015-4144, CVE-2015-4145)
- EAP-pwd peer: Fix asymmetric fragmentation behavior (CVE-2015-4146)
- NFC: Fix payload length validation in NDEF record parser (CVE-2015-8041)
- WNM: Ignore Key Data in WNM Sleep Mode Response frame if no PMF in use
  (CVE-2015-5310)
- EAP-pwd peer: Fix last fragment length validation (CVE-2015-5315)
- EAP-pwd server: Fix last fragment length validation (CVE-2015-5314)
- EAP-pwd peer: Fix error path for unexpected Confirm message (CVE-2015-5316)

Signed-off-by: Stefan Lippers-Hollmann <s.l-h@gmx.de>

SVN-Revision: 48185
This commit is contained in:
Felix Fietkau 2016-01-10 17:03:37 +00:00
parent a960fcef29
commit 6c40914c0c
11 changed files with 554 additions and 0 deletions

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@ -0,0 +1,49 @@
From 5acd23f4581da58683f3cf5e36cb71bbe4070bd7 Mon Sep 17 00:00:00 2001
From: Jouni Malinen <j@w1.fi>
Date: Tue, 28 Apr 2015 17:08:33 +0300
Subject: [PATCH] WPS: Fix HTTP chunked transfer encoding parser
strtoul() return value may end up overflowing the int h->chunk_size and
resulting in a negative value to be stored as the chunk_size. This could
result in the following memcpy operation using a very large length
argument which would result in a buffer overflow and segmentation fault.
This could have been used to cause a denial service by any device that
has been authorized for network access (either wireless or wired). This
would affect both the WPS UPnP functionality in a WPS AP (hostapd with
upnp_iface parameter set in the configuration) and WPS ER
(wpa_supplicant with WPS_ER_START control interface command used).
Validate the parsed chunk length value to avoid this. In addition to
rejecting negative values, we can also reject chunk size that would be
larger than the maximum configured body length.
Thanks to Kostya Kortchinsky of Google security team for discovering and
reporting this issue.
Signed-off-by: Jouni Malinen <j@w1.fi>
---
src/wps/httpread.c | 7 +++++++
1 file changed, 7 insertions(+)
diff --git a/src/wps/httpread.c b/src/wps/httpread.c
index 2f08f37..d2855e3 100644
--- a/src/wps/httpread.c
+++ b/src/wps/httpread.c
@@ -533,6 +533,13 @@ static void httpread_read_handler(int sd, void *eloop_ctx, void *sock_ctx)
if (!isxdigit(*cbp))
goto bad;
h->chunk_size = strtoul(cbp, NULL, 16);
+ if (h->chunk_size < 0 ||
+ h->chunk_size > h->max_bytes) {
+ wpa_printf(MSG_DEBUG,
+ "httpread: Invalid chunk size %d",
+ h->chunk_size);
+ goto bad;
+ }
/* throw away chunk header
* so we have only real data
*/
--
1.9.1

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@ -0,0 +1,73 @@
From dd2f043c9c43d156494e33d7ce22db96e6ef42c7 Mon Sep 17 00:00:00 2001
From: Jouni Malinen <j@w1.fi>
Date: Fri, 1 May 2015 16:37:45 +0300
Subject: [PATCH 1/5] EAP-pwd peer: Fix payload length validation for Commit
and Confirm
The length of the received Commit and Confirm message payloads was not
checked before reading them. This could result in a buffer read
overflow when processing an invalid message.
Fix this by verifying that the payload is of expected length before
processing it. In addition, enforce correct state transition sequence to
make sure there is no unexpected behavior if receiving a Commit/Confirm
message before the previous exchanges have been completed.
Thanks to Kostya Kortchinsky of Google security team for discovering and
reporting this issue.
Signed-off-by: Jouni Malinen <j@w1.fi>
---
src/eap_peer/eap_pwd.c | 29 +++++++++++++++++++++++++++++
1 file changed, 29 insertions(+)
diff --git a/src/eap_peer/eap_pwd.c b/src/eap_peer/eap_pwd.c
index f2b0926..a629437 100644
--- a/src/eap_peer/eap_pwd.c
+++ b/src/eap_peer/eap_pwd.c
@@ -355,6 +355,23 @@ eap_pwd_perform_commit_exchange(struct eap_sm *sm, struct eap_pwd_data *data,
BIGNUM *mask = NULL, *x = NULL, *y = NULL, *cofactor = NULL;
u16 offset;
u8 *ptr, *scalar = NULL, *element = NULL;
+ size_t prime_len, order_len;
+
+ if (data->state != PWD_Commit_Req) {
+ ret->ignore = TRUE;
+ goto fin;
+ }
+
+ prime_len = BN_num_bytes(data->grp->prime);
+ order_len = BN_num_bytes(data->grp->order);
+
+ if (payload_len != 2 * prime_len + order_len) {
+ wpa_printf(MSG_INFO,
+ "EAP-pwd: Unexpected Commit payload length %u (expected %u)",
+ (unsigned int) payload_len,
+ (unsigned int) (2 * prime_len + order_len));
+ goto fin;
+ }
if (((data->private_value = BN_new()) == NULL) ||
((data->my_element = EC_POINT_new(data->grp->group)) == NULL) ||
@@ -554,6 +571,18 @@ eap_pwd_perform_confirm_exchange(struct eap_sm *sm, struct eap_pwd_data *data,
u8 conf[SHA256_MAC_LEN], *cruft = NULL, *ptr;
int offset;
+ if (data->state != PWD_Confirm_Req) {
+ ret->ignore = TRUE;
+ goto fin;
+ }
+
+ if (payload_len != SHA256_MAC_LEN) {
+ wpa_printf(MSG_INFO,
+ "EAP-pwd: Unexpected Confirm payload length %u (expected %u)",
+ (unsigned int) payload_len, SHA256_MAC_LEN);
+ goto fin;
+ }
+
/*
* first build up the ciphersuite which is group | random_function |
* prf
--
1.9.1

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@ -0,0 +1,66 @@
From e28a58be26184c2a23f80b410e0997ef1bd5d578 Mon Sep 17 00:00:00 2001
From: Jouni Malinen <j@w1.fi>
Date: Fri, 1 May 2015 16:40:44 +0300
Subject: [PATCH 2/5] EAP-pwd server: Fix payload length validation for Commit
and Confirm
The length of the received Commit and Confirm message payloads was not
checked before reading them. This could result in a buffer read
overflow when processing an invalid message.
Fix this by verifying that the payload is of expected length before
processing it. In addition, enforce correct state transition sequence to
make sure there is no unexpected behavior if receiving a Commit/Confirm
message before the previous exchanges have been completed.
Thanks to Kostya Kortchinsky of Google security team for discovering and
reporting this issue.
Signed-off-by: Jouni Malinen <j@w1.fi>
---
src/eap_server/eap_server_pwd.c | 19 +++++++++++++++++++
1 file changed, 19 insertions(+)
diff --git a/src/eap_server/eap_server_pwd.c b/src/eap_server/eap_server_pwd.c
index 66bd5d2..3189105 100644
--- a/src/eap_server/eap_server_pwd.c
+++ b/src/eap_server/eap_server_pwd.c
@@ -656,9 +656,21 @@ eap_pwd_process_commit_resp(struct eap_sm *sm, struct eap_pwd_data *data,
BIGNUM *x = NULL, *y = NULL, *cofactor = NULL;
EC_POINT *K = NULL, *point = NULL;
int res = 0;
+ size_t prime_len, order_len;
wpa_printf(MSG_DEBUG, "EAP-pwd: Received commit response");
+ prime_len = BN_num_bytes(data->grp->prime);
+ order_len = BN_num_bytes(data->grp->order);
+
+ if (payload_len != 2 * prime_len + order_len) {
+ wpa_printf(MSG_INFO,
+ "EAP-pwd: Unexpected Commit payload length %u (expected %u)",
+ (unsigned int) payload_len,
+ (unsigned int) (2 * prime_len + order_len));
+ goto fin;
+ }
+
if (((data->peer_scalar = BN_new()) == NULL) ||
((data->k = BN_new()) == NULL) ||
((cofactor = BN_new()) == NULL) ||
@@ -774,6 +786,13 @@ eap_pwd_process_confirm_resp(struct eap_sm *sm, struct eap_pwd_data *data,
u8 conf[SHA256_MAC_LEN], *cruft = NULL, *ptr;
int offset;
+ if (payload_len != SHA256_MAC_LEN) {
+ wpa_printf(MSG_INFO,
+ "EAP-pwd: Unexpected Confirm payload length %u (expected %u)",
+ (unsigned int) payload_len, SHA256_MAC_LEN);
+ goto fin;
+ }
+
/* build up the ciphersuite: group | random_function | prf */
grp = htons(data->group_num);
ptr = (u8 *) &cs;
--
1.9.1

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@ -0,0 +1,52 @@
From 477c74395acd0123340457ba6f15ab345d42016e Mon Sep 17 00:00:00 2001
From: Jouni Malinen <j@w1.fi>
Date: Sat, 2 May 2015 19:23:04 +0300
Subject: [PATCH 3/5] EAP-pwd peer: Fix Total-Length parsing for fragment
reassembly
The remaining number of bytes in the message could be smaller than the
Total-Length field size, so the length needs to be explicitly checked
prior to reading the field and decrementing the len variable. This could
have resulted in the remaining length becoming negative and interpreted
as a huge positive integer.
In addition, check that there is no already started fragment in progress
before allocating a new buffer for reassembling fragments. This avoid a
potential memory leak when processing invalid message.
Signed-off-by: Jouni Malinen <j@w1.fi>
---
src/eap_peer/eap_pwd.c | 12 ++++++++++++
1 file changed, 12 insertions(+)
diff --git a/src/eap_peer/eap_pwd.c b/src/eap_peer/eap_pwd.c
index a629437..1d2079b 100644
--- a/src/eap_peer/eap_pwd.c
+++ b/src/eap_peer/eap_pwd.c
@@ -866,11 +866,23 @@ eap_pwd_process(struct eap_sm *sm, void *priv, struct eap_method_ret *ret,
* if it's the first fragment there'll be a length field
*/
if (EAP_PWD_GET_LENGTH_BIT(lm_exch)) {
+ if (len < 2) {
+ wpa_printf(MSG_DEBUG,
+ "EAP-pwd: Frame too short to contain Total-Length field");
+ ret->ignore = TRUE;
+ return NULL;
+ }
tot_len = WPA_GET_BE16(pos);
wpa_printf(MSG_DEBUG, "EAP-pwd: Incoming fragments whose "
"total length = %d", tot_len);
if (tot_len > 15000)
return NULL;
+ if (data->inbuf) {
+ wpa_printf(MSG_DEBUG,
+ "EAP-pwd: Unexpected new fragment start when previous fragment is still in use");
+ ret->ignore = TRUE;
+ return NULL;
+ }
data->inbuf = wpabuf_alloc(tot_len);
if (data->inbuf == NULL) {
wpa_printf(MSG_INFO, "Out of memory to buffer "
--
1.9.1

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@ -0,0 +1,50 @@
From 3035cc2894e08319b905bd6561e8bddc8c2db9fa Mon Sep 17 00:00:00 2001
From: Jouni Malinen <j@w1.fi>
Date: Sat, 2 May 2015 19:26:06 +0300
Subject: [PATCH 4/5] EAP-pwd server: Fix Total-Length parsing for fragment
reassembly
The remaining number of bytes in the message could be smaller than the
Total-Length field size, so the length needs to be explicitly checked
prior to reading the field and decrementing the len variable. This could
have resulted in the remaining length becoming negative and interpreted
as a huge positive integer.
In addition, check that there is no already started fragment in progress
before allocating a new buffer for reassembling fragments. This avoid a
potential memory leak when processing invalid message.
Signed-off-by: Jouni Malinen <j@w1.fi>
---
src/eap_server/eap_server_pwd.c | 10 ++++++++++
1 file changed, 10 insertions(+)
diff --git a/src/eap_server/eap_server_pwd.c b/src/eap_server/eap_server_pwd.c
index 3189105..2bfc3c2 100644
--- a/src/eap_server/eap_server_pwd.c
+++ b/src/eap_server/eap_server_pwd.c
@@ -942,11 +942,21 @@ static void eap_pwd_process(struct eap_sm *sm, void *priv,
* the first fragment has a total length
*/
if (EAP_PWD_GET_LENGTH_BIT(lm_exch)) {
+ if (len < 2) {
+ wpa_printf(MSG_DEBUG,
+ "EAP-pwd: Frame too short to contain Total-Length field");
+ return;
+ }
tot_len = WPA_GET_BE16(pos);
wpa_printf(MSG_DEBUG, "EAP-pwd: Incoming fragments, total "
"length = %d", tot_len);
if (tot_len > 15000)
return;
+ if (data->inbuf) {
+ wpa_printf(MSG_DEBUG,
+ "EAP-pwd: Unexpected new fragment start when previous fragment is still in use");
+ return;
+ }
data->inbuf = wpabuf_alloc(tot_len);
if (data->inbuf == NULL) {
wpa_printf(MSG_INFO, "EAP-pwd: Out of memory to "
--
1.9.1

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@ -0,0 +1,32 @@
From 28a069a545b06b99eb55ad53f63f2c99e65a98f6 Mon Sep 17 00:00:00 2001
From: Jouni Malinen <j@w1.fi>
Date: Sat, 2 May 2015 19:26:28 +0300
Subject: [PATCH 5/5] EAP-pwd peer: Fix asymmetric fragmentation behavior
The L (Length) and M (More) flags needs to be cleared before deciding
whether the locally generated response requires fragmentation. This
fixes an issue where these flags from the server could have been invalid
for the following message. In some cases, this could have resulted in
triggering the wpabuf security check that would terminate the process
due to invalid buffer allocation.
Signed-off-by: Jouni Malinen <j@w1.fi>
---
src/eap_peer/eap_pwd.c | 1 +
1 file changed, 1 insertion(+)
diff --git a/src/eap_peer/eap_pwd.c b/src/eap_peer/eap_pwd.c
index 1d2079b..e58b13a 100644
--- a/src/eap_peer/eap_pwd.c
+++ b/src/eap_peer/eap_pwd.c
@@ -968,6 +968,7 @@ eap_pwd_process(struct eap_sm *sm, void *priv, struct eap_method_ret *ret,
/*
* we have output! Do we need to fragment it?
*/
+ lm_exch = EAP_PWD_GET_EXCHANGE(lm_exch);
len = wpabuf_len(data->outbuf);
if ((len + EAP_PWD_HDR_SIZE) > data->mtu) {
resp = eap_msg_alloc(EAP_VENDOR_IETF, EAP_TYPE_PWD, data->mtu,
--
1.9.1

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From df9079e72760ceb7ebe7fb11538200c516bdd886 Mon Sep 17 00:00:00 2001
From: Jouni Malinen <j@w1.fi>
Date: Tue, 7 Jul 2015 21:57:28 +0300
Subject: [PATCH] NFC: Fix payload length validation in NDEF record parser
It was possible for the 32-bit record->total_length value to end up
wrapping around due to integer overflow if the longer form of payload
length field is used and record->payload_length gets a value close to
2^32. This could result in ndef_parse_record() accepting a too large
payload length value and the record type filter reading up to about 20
bytes beyond the end of the buffer and potentially killing the process.
This could also result in an attempt to allocate close to 2^32 bytes of
heap memory and if that were to succeed, a buffer read overflow of the
same length which would most likely result in the process termination.
In case of record->total_length ending up getting the value 0, there
would be no buffer read overflow, but record parsing would result in an
infinite loop in ndef_parse_records().
Any of these error cases could potentially be used for denial of service
attacks over NFC by using a malformed NDEF record on an NFC Tag or
sending them during NFC connection handover if the application providing
the NDEF message to hostapd/wpa_supplicant did no validation of the
received records. While such validation is likely done in the NFC stack
that needs to parse the NFC messages before further processing,
hostapd/wpa_supplicant better be prepared for any data being included
here.
Fix this by validating record->payload_length value in a way that
detects integer overflow. (CID 122668)
Signed-off-by: Jouni Malinen <j@w1.fi>
---
src/wps/ndef.c | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)
diff --git a/src/wps/ndef.c b/src/wps/ndef.c
index 5604b0a..50d018f 100644
--- a/src/wps/ndef.c
+++ b/src/wps/ndef.c
@@ -48,6 +48,8 @@ static int ndef_parse_record(const u8 *data, u32 size,
if (size < 6)
return -1;
record->payload_length = ntohl(*(u32 *)pos);
+ if (record->payload_length > size - 6)
+ return -1;
pos += sizeof(u32);
}
@@ -68,7 +70,8 @@ static int ndef_parse_record(const u8 *data, u32 size,
pos += record->payload_length;
record->total_length = pos - data;
- if (record->total_length > size)
+ if (record->total_length > size ||
+ record->total_length < record->payload_length)
return -1;
return 0;
}
--
1.9.1

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From 6b12d93d2c7428a34bfd4b3813ba339ed57b698a Mon Sep 17 00:00:00 2001
From: Jouni Malinen <j@w1.fi>
Date: Sun, 25 Oct 2015 15:45:50 +0200
Subject: [PATCH] WNM: Ignore Key Data in WNM Sleep Mode Response frame if no
PMF in use
WNM Sleep Mode Response frame is used to update GTK/IGTK only if PMF is
enabled. Verify that PMF is in use before using this field on station
side to avoid accepting unauthenticated key updates. (CVE-2015-5310)
Signed-off-by: Jouni Malinen <j@w1.fi>
---
wpa_supplicant/wnm_sta.c | 6 ++++++
1 file changed, 6 insertions(+)
diff --git a/wpa_supplicant/wnm_sta.c b/wpa_supplicant/wnm_sta.c
index 954de67..7d79499 100644
--- a/wpa_supplicant/wnm_sta.c
+++ b/wpa_supplicant/wnm_sta.c
@@ -187,6 +187,12 @@ static void wnm_sleep_mode_exit_success(struct wpa_supplicant *wpa_s,
end = ptr + key_len_total;
wpa_hexdump_key(MSG_DEBUG, "WNM: Key Data", ptr, key_len_total);
+ if (key_len_total && !wpa_sm_pmf_enabled(wpa_s->wpa)) {
+ wpa_msg(wpa_s, MSG_INFO,
+ "WNM: Ignore Key Data in WNM-Sleep Mode Response - PMF not enabled");
+ return;
+ }
+
while (ptr + 1 < end) {
if (ptr + 2 + ptr[1] > end) {
wpa_printf(MSG_DEBUG, "WNM: Invalid Key Data element "

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@ -0,0 +1,54 @@
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

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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

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@ -0,0 +1,34 @@
From 95577884ca4fa76be91344ff7a8d5d1e6dc3da61 Mon Sep 17 00:00:00 2001
From: Jouni Malinen <j@w1.fi>
Date: Sun, 1 Nov 2015 19:35:44 +0200
Subject: [PATCH] EAP-pwd peer: Fix error path for unexpected Confirm message
If the Confirm message is received from the server before the Identity
exchange has been completed, the group has not yet been determined and
data->grp is NULL. The error path in eap_pwd_perform_confirm_exchange()
did not take this corner case into account and could end up
dereferencing a NULL pointer and terminating the process if invalid
message sequence is received. (CVE-2015-5316)
Signed-off-by: Jouni Malinen <j@w1.fi>
---
src/eap_peer/eap_pwd.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/src/eap_peer/eap_pwd.c b/src/eap_peer/eap_pwd.c
index 75ceef1..892b590 100644
--- a/src/eap_peer/eap_pwd.c
+++ b/src/eap_peer/eap_pwd.c
@@ -774,7 +774,8 @@ eap_pwd_perform_confirm_exchange(struct eap_sm *sm, struct eap_pwd_data *data,
wpabuf_put_data(data->outbuf, conf, SHA256_MAC_LEN);
fin:
- bin_clear_free(cruft, BN_num_bytes(data->grp->prime));
+ if (data->grp)
+ bin_clear_free(cruft, BN_num_bytes(data->grp->prime));
BN_clear_free(x);
BN_clear_free(y);
if (data->outbuf == NULL) {
--
1.9.1