Return-path: Received: from charlotte.tuxdriver.com ([70.61.120.58]:36258 "EHLO smtp.tuxdriver.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757911Ab3LFQPQ (ORCPT ); Fri, 6 Dec 2013 11:15:16 -0500 Date: Fri, 6 Dec 2013 11:12:58 -0500 From: "John W. Linville" To: Eugene Krasnikov Cc: Michal Nazarewicz , Peter Stuge , ath9k-devel , linux-wireless , "linux-kernel@vger.kernel.org" Subject: Re: [PATCHv2] net: wireless: wcn36xx: fix potential NULL pointer dereference Message-ID: <20131206161258.GC13285@tuxdriver.com> (sfid-20131206_171538_047571_FF6FA51D) References: <1385744870-10164-1-git-send-email-mpn@google.com> <20131201004715.11125.qmail@stuge.se> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 In-Reply-To: Sender: linux-wireless-owner@vger.kernel.org List-ID: FWIW, I merged the earlier version. Please send any changes as a follow-up patch, probably against wireless-next. John On Thu, Dec 05, 2013 at 08:41:29AM +0000, Eugene Krasnikov wrote: > > + if (msg_ind) > > + break; > > + /* FIXME: Do something smarter then just printing an error. */ > > + wcn36xx_err("Run out of memory while handling SMD_EVENT (%d)\n", > > I think code will look neater if error case will be handled in "else" > statement something like: > if (msg_ind) { > ... > } else { > /*print message*/ > } > /*unlock and break;*/ > > How about that? > > > On Mon, Dec 2, 2013 at 1:09 PM, Michal Nazarewicz wrote: > > > > If kmalloc fails wcn36xx_smd_rsp_process will attempt to dereference > > a NULL pointer. There might be a better error recovery then just > > printing an error, but printing an error message is better then the > > current behaviour. > > > > Signed-off-by: Michal Nazarewicz > > --- > > drivers/net/wireless/ath/wcn36xx/smd.c | 19 +++++++++++++------ > > 1 file changed, 13 insertions(+), 6 deletions(-) > > > > On Sun, Dec 01 2013, Peter Stuge wrote: > >> Michal Nazarewicz wrote: > >>> + wcn36xx_err("Run out of memory while hnadling SMD_EVENT (%d)\n", > >>> + msg_header->msg_type); > >> > >> Typo hnadling. > > > > Fixed. > > > > diff --git a/drivers/net/wireless/ath/wcn36xx/smd.c b/drivers/net/wireless/ath/wcn36xx/smd.c > > index de9eb2c..3663394 100644 > > --- a/drivers/net/wireless/ath/wcn36xx/smd.c > > +++ b/drivers/net/wireless/ath/wcn36xx/smd.c > > @@ -2041,13 +2041,20 @@ static void wcn36xx_smd_rsp_process(struct wcn36xx *wcn, void *buf, size_t len) > > case WCN36XX_HAL_DELETE_STA_CONTEXT_IND: > > mutex_lock(&wcn->hal_ind_mutex); > > msg_ind = kmalloc(sizeof(*msg_ind), GFP_KERNEL); > > - msg_ind->msg_len = len; > > - msg_ind->msg = kmalloc(len, GFP_KERNEL); > > - memcpy(msg_ind->msg, buf, len); > > - list_add_tail(&msg_ind->list, &wcn->hal_ind_queue); > > - queue_work(wcn->hal_ind_wq, &wcn->hal_ind_work); > > - wcn36xx_dbg(WCN36XX_DBG_HAL, "indication arrived\n"); > > + if (msg_ind) { > > + msg_ind->msg_len = len; > > + msg_ind->msg = kmalloc(len, GFP_KERNEL); > > + memcpy(msg_ind->msg, buf, len); > > + list_add_tail(&msg_ind->list, &wcn->hal_ind_queue); > > + queue_work(wcn->hal_ind_wq, &wcn->hal_ind_work); > > + wcn36xx_dbg(WCN36XX_DBG_HAL, "indication arrived\n"); > > + } > > mutex_unlock(&wcn->hal_ind_mutex); > > + if (msg_ind) > > + break; > > + /* FIXME: Do something smarter then just printing an error. */ > > + wcn36xx_err("Run out of memory while handling SMD_EVENT (%d)\n", > > + msg_header->msg_type); > > break; > > default: > > wcn36xx_err("SMD_EVENT (%d) not supported\n", > > -- > > 1.8.4.1 > > > > -- > > Best regards, _ _ > > .o. | Liege of Serenely Enlightened Majesty of o' \,=./ `o > > ..o | Computer Science, Michał “mina86” Nazarewicz (o o) > > ooo +------ooO--(_)--Ooo-- > > > > -- > Best regards, > Eugene > -- John W. Linville Someday the world will need a hero, and you linville@tuxdriver.com might be all we have. Be ready.