Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752827AbbHaUxn (ORCPT ); Mon, 31 Aug 2015 16:53:43 -0400 Received: from mail-qk0-f178.google.com ([209.85.220.178]:36022 "EHLO mail-qk0-f178.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752477AbbHaUxl (ORCPT ); Mon, 31 Aug 2015 16:53:41 -0400 Subject: Re: [PATCH] lpfc: Fix possible use-after-free and double free in lpfc_mbx_cmpl_rdp_page_a2() To: Sebastian Herbszt , Johannes Thumshirn , Dick Kennedy References: <1439809382-32419-1-git-send-email-jthumshirn@suse.de> <20150817232634.00006d80@localhost> <20150819002751.00000f06@localhost> Cc: "James E.J. Bottomley" , linux-scsi@vger.kernel.org, linux-kernel@vger.kernel.org, Colin King From: James Smart Message-ID: <55E4BED1.7050201@avagotech.com> Date: Mon, 31 Aug 2015 16:53:37 -0400 User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:38.0) Gecko/20100101 Thunderbird/38.2.0 MIME-Version: 1.0 In-Reply-To: <20150819002751.00000f06@localhost> Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1430 Lines: 42 On 8/18/2015 6:27 PM, Sebastian Herbszt wrote: > Johannes Thumshirn wrote: >> Sebastian Herbszt writes: >> >>> Johannes Thumshirn wrote: >>>> If the bf_get() call in lpfc_mbx_cmpl_rdp_page_a2() does succeeds, execution >>>> continues normally and mp gets kfree()d. >>>> >>>> If the subsequent call to lpfc_sli_issue_mbox() fails execution jumps to the >>>> error label where lpfc_mbuf_free() is called with mp->virt and mp->phys as >>>> function arguments. This is the use after free. Following the use after free mp >>>> gets kfree()d again which is a double free. >>> A similar patch was posted by Colin Ian King on 2015-07-31 [1]. >>> >>> [1] http://marc.info/?l=linux-scsi&m=143835937206204&w=2 >> OK, >> >> Is it already in James' tree (haven't checked)? The problematic code was >> merged for 4.2-rc1 so if the fix (Collin's or mine I don't care) could go >> in while we're still in the rc phase, we could avoid all that stable >> circus. >> >> Thanks for digging this out. >> >> Byte, >> Johannes > It is not yet in scsi.git. > > James S., Dick, which patch do you prefer? > > Sebastian I looked at both and liked Johannes patch better. -- james s -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/