From 95577884ca4fa76be91344ff7a8d5d1e6dc3da61 Mon Sep 17 00:00:00 2001 From: Jouni Malinen 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 --- 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