From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.linuxfoundation.org ([140.211.169.12]:60042 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753639AbeC2SHd (ORCPT ); Thu, 29 Mar 2018 14:07:33 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Johannes Thumshirn , Andrey Konovalov , Hannes Reinecke , Christoph Hellwig , Doug Gilbert , "Martin K. Petersen" , Tony Battersby Subject: [PATCH 4.4 01/20] scsi: sg: dont return bogus Sg_requests Date: Thu, 29 Mar 2018 20:00:37 +0200 Message-Id: <20180329175741.949669985@linuxfoundation.org> In-Reply-To: <20180329175741.886181131@linuxfoundation.org> References: <20180329175741.886181131@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: stable-owner@vger.kernel.org List-ID: 4.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Johannes Thumshirn commit 48ae8484e9fc324b4968d33c585e54bc98e44d61 upstream. 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: Doug Gilbert Signed-off-by: Martin K. Petersen Cc: Tony Battersby Signed-off-by: Greg Kroah-Hartman --- drivers/scsi/sg.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) --- 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 */