From mboxrd@z Thu Jan 1 00:00:00 1970 From: Tilman Schmidt Subject: [PATCH 3/4] isdn: avoid races in capidrv Date: Sun, 6 Sep 2009 20:58:52 +0200 (CEST) Message-ID: <20090906-patch-capi-3.tilman@imap.cc> References: <20090906-patch-capi-0.tilman@imap.cc> Cc: Carsten Paeth To: davem@davemloft.net, Karsten Keil , linux-kernel@vger.kernel.org, netdev@vger.kernel.org, i4ldeveloper@listserv.isdn4linux.de Return-path: In-Reply-To: <20090906-patch-capi-0.tilman@imap.cc> Sender: linux-kernel-owner@vger.kernel.org List-Id: netdev.vger.kernel.org In several places, capidrv sends a CAPI message to the ISDN device and then updates its internal state accordingly. If the response message from the device arrives before the state is updated, it may be rejected or processed incorrectly. Avoid these races by updating the state before emitting the message. Signed-off-by: Tilman Schmidt Acked-by: Karsten Keil --- drivers/isdn/capi/capidrv.c | 24 ++++++++++++------------ 1 files changed, 12 insertions(+), 12 deletions(-) diff --git a/drivers/isdn/capi/capidrv.c b/drivers/isdn/capi/capidrv.c index 6501202..c3f5472 100644 --- a/drivers/isdn/capi/capidrv.c +++ b/drivers/isdn/capi/capidrv.c @@ -671,8 +671,8 @@ static void n0(capidrv_contr * card, capidrv_ncci * ncci) NULL, /* Useruserdata */ /* $$$$ */ NULL /* Facilitydataarray */ ); - send_message(card, &cmsg); plci_change_state(card, ncci->plcip, EV_PLCI_DISCONNECT_REQ); + send_message(card, &cmsg); cmd.command = ISDN_STAT_BHUP; cmd.driver = card->myid; @@ -924,8 +924,8 @@ static void handle_incoming_call(capidrv_contr * card, _cmsg * cmsg) */ capi_cmsg_answer(cmsg); cmsg->Reject = 1; /* ignore */ - send_message(card, cmsg); plci_change_state(card, plcip, EV_PLCI_CONNECT_REJECT); + send_message(card, cmsg); printk(KERN_INFO "capidrv-%d: incoming call %s,%d,%d,%s ignored\n", card->contrnr, cmd.parm.setup.phone, @@ -974,8 +974,8 @@ static void handle_incoming_call(capidrv_contr * card, _cmsg * cmsg) case 2: /* Call will be rejected. */ capi_cmsg_answer(cmsg); cmsg->Reject = 2; /* reject call, normal call clearing */ - send_message(card, cmsg); plci_change_state(card, plcip, EV_PLCI_CONNECT_REJECT); + send_message(card, cmsg); break; default: @@ -983,8 +983,8 @@ static void handle_incoming_call(capidrv_contr * card, _cmsg * cmsg) capi_cmsg_answer(cmsg); cmsg->Reject = 8; /* reject call, destination out of order */ - send_message(card, cmsg); plci_change_state(card, plcip, EV_PLCI_CONNECT_REJECT); + send_message(card, cmsg); break; } return; @@ -1020,8 +1020,8 @@ static void handle_plci(_cmsg * cmsg) card->bchans[plcip->chan].disconnecting = 1; plci_change_state(card, plcip, EV_PLCI_DISCONNECT_IND); capi_cmsg_answer(cmsg); - send_message(card, cmsg); plci_change_state(card, plcip, EV_PLCI_DISCONNECT_RESP); + send_message(card, cmsg); break; case CAPI_DISCONNECT_CONF: /* plci */ @@ -1078,8 +1078,8 @@ static void handle_plci(_cmsg * cmsg) if (card->bchans[plcip->chan].incoming) { capi_cmsg_answer(cmsg); - send_message(card, cmsg); plci_change_state(card, plcip, EV_PLCI_CONNECT_ACTIVE_IND); + send_message(card, cmsg); } else { capidrv_ncci *nccip; capi_cmsg_answer(cmsg); @@ -1098,13 +1098,13 @@ static void handle_plci(_cmsg * cmsg) NULL /* NCPI */ ); nccip->msgid = cmsg->Messagenumber; + plci_change_state(card, plcip, EV_PLCI_CONNECT_ACTIVE_IND); + ncci_change_state(card, nccip, EV_NCCI_CONNECT_B3_REQ); send_message(card, cmsg); cmd.command = ISDN_STAT_DCONN; cmd.driver = card->myid; cmd.arg = plcip->chan; card->interface.statcallb(&cmd); - plci_change_state(card, plcip, EV_PLCI_CONNECT_ACTIVE_IND); - ncci_change_state(card, nccip, EV_NCCI_CONNECT_B3_REQ); } break; @@ -1193,8 +1193,8 @@ static void handle_ncci(_cmsg * cmsg) goto notfound; capi_cmsg_answer(cmsg); - send_message(card, cmsg); ncci_change_state(card, nccip, EV_NCCI_CONNECT_B3_ACTIVE_IND); + send_message(card, cmsg); cmd.command = ISDN_STAT_BCONN; cmd.driver = card->myid; @@ -1222,8 +1222,8 @@ static void handle_ncci(_cmsg * cmsg) 0, /* Reject */ NULL /* NCPI */ ); - send_message(card, cmsg); ncci_change_state(card, nccip, EV_NCCI_CONNECT_B3_RESP); + send_message(card, cmsg); break; } printk(KERN_ERR "capidrv-%d: no mem for ncci, sorry\n", card->contrnr); @@ -1299,8 +1299,8 @@ static void handle_ncci(_cmsg * cmsg) card->bchans[nccip->chan].disconnecting = 1; ncci_change_state(card, nccip, EV_NCCI_DISCONNECT_B3_IND); capi_cmsg_answer(cmsg); - send_message(card, cmsg); ncci_change_state(card, nccip, EV_NCCI_DISCONNECT_B3_RESP); + send_message(card, cmsg); break; case CAPI_DISCONNECT_B3_CONF: /* ncci */ @@ -2014,8 +2014,8 @@ static void send_listen(capidrv_contr *card) card->cipmask, card->cipmask2, NULL, NULL); - send_message(card, &cmdcmsg); listen_change_state(card, EV_LISTEN_REQ); + send_message(card, &cmdcmsg); } static void listentimerfunc(unsigned long x) -- 1.6.2.1.214.ge986c