From patchwork Wed May 10 07:53:40 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Johannes Thumshirn X-Patchwork-Id: 9719383 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id D810160236 for ; Wed, 10 May 2017 07:54:04 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id C859D284E3 for ; Wed, 10 May 2017 07:54:04 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id BCAA92857B; Wed, 10 May 2017 07:54:04 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.9 required=2.0 tests=BAYES_00,RCVD_IN_DNSWL_HI autolearn=unavailable version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 6F6F6284E3 for ; Wed, 10 May 2017 07:54:04 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751423AbdEJHxw (ORCPT ); Wed, 10 May 2017 03:53:52 -0400 Received: from mx2.suse.de ([195.135.220.15]:45656 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1751081AbdEJHxw (ORCPT ); Wed, 10 May 2017 03:53:52 -0400 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (charybdis-ext.suse.de [195.135.220.254]) by mx1.suse.de (Postfix) with ESMTP id 98C13AAB6; Wed, 10 May 2017 07:53:50 +0000 (UTC) From: Johannes Thumshirn To: "Martin K . Petersen" Cc: James Bottomley , Andrey Konovalov , Linux Kernel Mailinglist , Linux SCSI Mailinglist , Johannes Thumshirn , Hannes Reinecke , Christoph Hellwig , Doug Gilbert Subject: [PATCH v2] scsi: sg: don't return bogus Sg_requests Date: Wed, 10 May 2017 09:53:40 +0200 Message-Id: <20170510075340.12125-1-jthumshirn@suse.de> X-Mailer: git-send-email 2.12.0 Sender: linux-scsi-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-scsi@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP If the list search in sg_get_rq_mark() fails to find a valid request, we return a bogus element. This then can later lead to a GPF in sg_remove_scat(). So don't return bogus Sg_requests in sg_get_rq_mark() but NULL in case the list search doesn't find a valid request. Signed-off-by: Johannes Thumshirn Reported-by: Andrey Konovalov Cc: Hannes Reinecke Cc: Christoph Hellwig Cc: Doug Gilbert Reviewed-by: Hannes Reinecke Acked-by: Douglas Gilbert --- Changes to v1: * Directly return found element within the loop (Hannes) drivers/scsi/sg.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/drivers/scsi/sg.c b/drivers/scsi/sg.c index 0a38ba01b7b4..82c33a6edbea 100644 --- a/drivers/scsi/sg.c +++ b/drivers/scsi/sg.c @@ -2074,11 +2074,12 @@ sg_get_rq_mark(Sg_fd * sfp, int pack_id) if ((1 == resp->done) && (!resp->sg_io_owned) && ((-1 == pack_id) || (resp->header.pack_id == pack_id))) { resp->done = 2; /* guard against other readers */ - break; + write_unlock_irqrestore(&sfp->rq_list_lock, iflags); + return resp; } } write_unlock_irqrestore(&sfp->rq_list_lock, iflags); - return resp; + return NULL; } /* always adds to end of list */