[PATCH AUTOSEL 5.5 517/542] iwlwifi: mvm: avoid use after free for pmsr request

From: Sasha Levin
Date: Fri Feb 14 2020 - 11:00:07 EST


From: Avraham Stern <avraham.stern@xxxxxxxxx>

[ Upstream commit cc4255eff523f25187bb95561642941de0e57497 ]

When a FTM request is aborted, the driver sends the abort command to
the fw and waits for a response. When the response arrives, the driver
calls cfg80211_pmsr_complete() for that request.
However, cfg80211 frees the requested data immediately after sending
the abort command, so this may lead to use after free.

Fix it by clearing the request data in the driver when the abort
command arrives and ignoring the fw notification that will come
afterwards.

Signed-off-by: Avraham Stern <avraham.stern@xxxxxxxxx>
Fixes: fc36ffda3267 ("iwlwifi: mvm: support FTM initiator")
Signed-off-by: Luca Coelho <luciano.coelho@xxxxxxxxx>
Signed-off-by: Kalle Valo <kvalo@xxxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/net/wireless/intel/iwlwifi/mvm/ftm-initiator.c | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/drivers/net/wireless/intel/iwlwifi/mvm/ftm-initiator.c b/drivers/net/wireless/intel/iwlwifi/mvm/ftm-initiator.c
index 9f4b117db9d7f..d47f76890cf9a 100644
--- a/drivers/net/wireless/intel/iwlwifi/mvm/ftm-initiator.c
+++ b/drivers/net/wireless/intel/iwlwifi/mvm/ftm-initiator.c
@@ -8,6 +8,7 @@
* Copyright(c) 2015 - 2017 Intel Deutschland GmbH
* Copyright (C) 2018 Intel Corporation
* Copyright (C) 2019 Intel Corporation
+ * Copyright (C) 2020 Intel Corporation
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of version 2 of the GNU General Public License as
@@ -30,6 +31,7 @@
* Copyright(c) 2015 - 2017 Intel Deutschland GmbH
* Copyright (C) 2018 Intel Corporation
* Copyright (C) 2019 Intel Corporation
+ * Copyright (C) 2020 Intel Corporation
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
@@ -389,6 +391,8 @@ void iwl_mvm_ftm_abort(struct iwl_mvm *mvm, struct cfg80211_pmsr_request *req)
if (req != mvm->ftm_initiator.req)
return;

+ iwl_mvm_ftm_reset(mvm);
+
if (iwl_mvm_send_cmd_pdu(mvm, iwl_cmd_id(TOF_RANGE_ABORT_CMD,
LOCATION_GROUP, 0),
0, sizeof(cmd), &cmd))
@@ -502,7 +506,6 @@ void iwl_mvm_ftm_range_resp(struct iwl_mvm *mvm, struct iwl_rx_cmd_buffer *rxb)
lockdep_assert_held(&mvm->mutex);

if (!mvm->ftm_initiator.req) {
- IWL_ERR(mvm, "Got FTM response but have no request?\n");
return;
}

--
2.20.1