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