Return-path: Received: from mail-ve0-f181.google.com ([209.85.128.181]:34123 "EHLO mail-ve0-f181.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752843Ab3LEIla convert rfc822-to-8bit (ORCPT ); Thu, 5 Dec 2013 03:41:30 -0500 MIME-Version: 1.0 In-Reply-To: References: <1385744870-10164-1-git-send-email-mpn@google.com> <20131201004715.11125.qmail@stuge.se> Date: Thu, 5 Dec 2013 08:41:29 +0000 Message-ID: (sfid-20131205_094146_463907_65E0A0DA) Subject: Re: [PATCHv2] net: wireless: wcn36xx: fix potential NULL pointer dereference From: Eugene Krasnikov To: Michal Nazarewicz Cc: Peter Stuge , "John W. Linville" , ath9k-devel , linux-wireless , "linux-kernel@vger.kernel.org" Content-Type: text/plain; charset=UTF-8 Sender: linux-wireless-owner@vger.kernel.org List-ID: > + 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