Return-path: Received: from mail-pf0-f181.google.com ([209.85.192.181]:36313 "EHLO mail-pf0-f181.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750805AbdIITad (ORCPT ); Sat, 9 Sep 2017 15:30:33 -0400 Received: by mail-pf0-f181.google.com with SMTP id e199so8831118pfh.3 for ; Sat, 09 Sep 2017 12:30:33 -0700 (PDT) From: Kevin Cernekee To: arend.vanspriel@broadcom.com, franky.lin@broadcom.com Cc: brcm80211-dev-list.pdl@broadcom.com, linux-wireless@vger.kernel.org, mnissler@chromium.org Subject: [PATCH V2 1/3] brcmfmac: Avoid possible out-of-bounds read Date: Sat, 9 Sep 2017 12:30:18 -0700 Message-Id: <20170909193020.19061-1-cernekee@chromium.org> (sfid-20170909_213037_442232_FED34112) Sender: linux-wireless-owner@vger.kernel.org List-ID: In brcmf_p2p_notify_rx_mgmt_p2p_probereq(), chanspec is assigned before the length of rxframe is validated. This could lead to uninitialized data being accessed (but not printed). Since we already have a perfectly good endian-swapped copy of rxframe->chanspec in ch.chspec, and ch.chspec is not modified by decchspec(), avoid the extra assignment and use ch.chspec in the debug print. Suggested-by: Mattias Nissler Signed-off-by: Kevin Cernekee Reviewed-by: Arend van Spriel --- drivers/net/wireless/broadcom/brcm80211/brcmfmac/p2p.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) V1->V2: Clarify changelog re: whether the uninitialized data is printed. diff --git a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/p2p.c b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/p2p.c index 2ce675ab40ef..1c450c0727cb 100644 --- a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/p2p.c +++ b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/p2p.c @@ -1853,7 +1853,6 @@ s32 brcmf_p2p_notify_rx_mgmt_p2p_probereq(struct brcmf_if *ifp, struct afx_hdl *afx_hdl = &p2p->afx_hdl; struct brcmf_cfg80211_vif *vif = ifp->vif; struct brcmf_rx_mgmt_data *rxframe = (struct brcmf_rx_mgmt_data *)data; - u16 chanspec = be16_to_cpu(rxframe->chanspec); struct brcmu_chan ch; u8 *mgmt_frame; u32 mgmt_frame_len; @@ -1906,7 +1905,7 @@ s32 brcmf_p2p_notify_rx_mgmt_p2p_probereq(struct brcmf_if *ifp, cfg80211_rx_mgmt(&vif->wdev, freq, 0, mgmt_frame, mgmt_frame_len, 0); brcmf_dbg(INFO, "mgmt_frame_len (%d) , e->datalen (%d), chanspec (%04x), freq (%d)\n", - mgmt_frame_len, e->datalen, chanspec, freq); + mgmt_frame_len, e->datalen, ch.chspec, freq); return 0; } -- 2.14.1.581.gf28d330327-goog