From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Date: Mon, 24 Aug 2015 13:03:07 +0300 From: Johan Hedberg To: Nicholas Krause Cc: linux-bluetooth@vger.kernel.org Subject: Re: [PATCH] bluetooth:Fix error checking in the function sc_dhkey_check Message-ID: <20150824100307.GD6958@t440s.lan> References: <1439948875-19807-1-git-send-email-xerofoify@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: <1439948875-19807-1-git-send-email-xerofoify@gmail.com> Sender: linux-bluetooth-owner@vger.kernel.org List-ID: Hi Nicholas, (unneeded recipients removed again) On Tue, Aug 18, 2015, Nicholas Krause wrote: > This fixes error checking in the function sc_dhkey_check by > properly checking if the internal call to the function smp_f6 > has failed by returning a error code as we must return to the > caller immediately if this internal call fails as we cannot Looks like the last sentence above is incomplete. > --- a/net/bluetooth/smp.c > +++ b/net/bluetooth/smp.c > @@ -1460,8 +1460,9 @@ static void sc_dhkey_check(struct smp_chan *smp) > if (smp->method == REQ_OOB) > memcpy(r, smp->rr, 16); > > - smp_f6(smp->tfm_cmac, smp->mackey, smp->prnd, smp->rrnd, r, io_cap, > - local_addr, remote_addr, check.e); > + if (smp_f6(smp->tfm_cmac, smp->mackey, smp->prnd, smp->rrnd, r, io_cap, > + local_addr, remote_addr, check.e)) > + return; This could cause the pairing procedure to get stuck because the remote is expecting the DHKey Check PDU from us and instead we never send anything. Probably the better solution is to make sc_dhkey_check() return an SMP error and then pass that up the call stack if necessary, similar to what sc_passkey_round() does. Johan