From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757140Ab0EFNWc (ORCPT ); Thu, 6 May 2010 09:22:32 -0400 Received: from fwil.voltaire.com ([193.47.165.2]:42259 "EHLO exil.voltaire.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1751208Ab0EFNWa (ORCPT ); Thu, 6 May 2010 09:22:30 -0400 Message-ID: <4BE2C28D.1090108@Voltaire.com> Date: Thu, 06 May 2010 16:22:21 +0300 From: Or Gerlitz User-Agent: Thunderbird 2.0.0.19 (X11/20081209) MIME-Version: 1.0 To: Roland Dreier CC: Dan Carpenter , Jiri Slaby , linux-kernel@vger.kernel.org, jirislaby@gmail.com, linux-rdma Subject: Re: [patch v3] infiniband: ulp/iser, fix error retval in iser_create_ib_conn_res References: <1268750962-13547-1-git-send-email-jslaby@suse.cz> <20100317151122.GF5331@bicker> <20100402112736.GH5265@bicker> In-Reply-To: Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit X-OriginalArrivalTime: 06 May 2010 13:22:25.0739 (UTC) FILETIME=[2B2981B0:01CAED1F] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Roland Dreier wrote: > Or, I don't think we ever fixed this. This patch looks correct to me, > any problem with merging this for 2.6.35? Roland, please use V4 below, the patch is okay and would apply before and after applying the multipathing patches I sent yesterday (same goes for them). [PATCH V4] ib/iser: fix error flow in iser_create_ib_conn_res From: Dan Carpenter We shouldn't free things here because we free them later. The call tree looks like this: iser_connect() ==> initiating the connection establishment and later iser_cma_handler() => iser_route_handler() => iser_create_ib_conn_res() if we fail here, eventually iser_conn_release() is called, resulted in double free. Signed-off-by: Dan Carpenter Signed-off-by: Or Gerlitz --- V1 fixed unreachable code V2 noticed that the original code had a double free V3 Roland Dreier points out that I left a dangling ERR_PTR() in "ib_conn->fmr_pool" which would be freed later on. V4 reviewed/enhanced the change-log --- drivers/infiniband/ulp/iser/iser_verbs.c | 25 +++++++++---------------- 1 file changed, 9 insertions(+), 16 deletions(-) Index: linux-2.6.34-rc6/drivers/infiniband/ulp/iser/iser_verbs.c =================================================================== --- linux-2.6.34-rc6.orig/drivers/infiniband/ulp/iser/iser_verbs.c +++ linux-2.6.34-rc6/drivers/infiniband/ulp/iser/iser_verbs.c @@ -163,10 +163,8 @@ static int iser_create_ib_conn_res(struc device = ib_conn->device; ib_conn->login_buf = kmalloc(ISER_RX_LOGIN_SIZE, GFP_KERNEL); - if (!ib_conn->login_buf) { - goto alloc_err; - ret = -ENOMEM; - } + if (!ib_conn->login_buf) + goto out_err; ib_conn->login_dma = ib_dma_map_single(ib_conn->device->ib_device, (void *)ib_conn->login_buf, ISER_RX_LOGIN_SIZE, @@ -175,10 +173,9 @@ static int iser_create_ib_conn_res(struc ib_conn->page_vec = kmalloc(sizeof(struct iser_page_vec) + (sizeof(u64) * (ISCSI_ISER_SG_TABLESIZE +1)), GFP_KERNEL); - if (!ib_conn->page_vec) { - ret = -ENOMEM; - goto alloc_err; - } + if (!ib_conn->page_vec) + goto out_err; + ib_conn->page_vec->pages = (u64 *) (ib_conn->page_vec + 1); params.page_shift = SHIFT_4K; @@ -198,7 +195,8 @@ static int iser_create_ib_conn_res(struc ib_conn->fmr_pool = ib_create_fmr_pool(device->pd, ¶ms); if (IS_ERR(ib_conn->fmr_pool)) { ret = PTR_ERR(ib_conn->fmr_pool); - goto fmr_pool_err; + ib_conn->fmr_pool = NULL; + goto out_err; } memset(&init_attr, 0, sizeof init_attr); @@ -216,7 +214,7 @@ static int iser_create_ib_conn_res(struc ret = rdma_create_qp(ib_conn->cma_id, device->pd, &init_attr); if (ret) - goto qp_err; + goto out_err; ib_conn->qp = ib_conn->cma_id->qp; iser_err("setting conn %p cma_id %p: fmr_pool %p qp %p\n", @@ -224,12 +222,7 @@ static int iser_create_ib_conn_res(struc ib_conn->fmr_pool, ib_conn->cma_id->qp); return ret; -qp_err: - (void)ib_destroy_fmr_pool(ib_conn->fmr_pool); -fmr_pool_err: - kfree(ib_conn->page_vec); - kfree(ib_conn->login_buf); -alloc_err: +out_err: iser_err("unable to alloc mem or create resource, err %d\n", ret); return ret; }