From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752974AbcISR5X (ORCPT ); Mon, 19 Sep 2016 13:57:23 -0400 Received: from mail-pa0-f51.google.com ([209.85.220.51]:34754 "EHLO mail-pa0-f51.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752040AbcISR5W (ORCPT ); Mon, 19 Sep 2016 13:57:22 -0400 Date: Mon, 19 Sep 2016 10:57:19 -0700 From: Omar Sandoval To: Alexander Gordeev Cc: linux-kernel@vger.kernel.org, linux-block@vger.kernel.org Subject: Re: [PATCH 09/14] blk-mq: Move duplicating code to blk_mq_exit_hctx() Message-ID: <20160919175719.GB21803@vader> References: <08fde52dea32101ca7fffe1ff6e1a4786a7eab2c.1474183901.git.agordeev@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <08fde52dea32101ca7fffe1ff6e1a4786a7eab2c.1474183901.git.agordeev@redhat.com> User-Agent: Mutt/1.7.0 (2016-08-17) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sun, Sep 18, 2016 at 09:37:19AM +0200, Alexander Gordeev wrote: > CC: linux-block@vger.kernel.org > Signed-off-by: Alexander Gordeev > --- > block/blk-mq.c | 14 +++++--------- > 1 file changed, 5 insertions(+), 9 deletions(-) > > diff --git a/block/blk-mq.c b/block/blk-mq.c > index 3efb700..cd32a08 100644 > --- a/block/blk-mq.c > +++ b/block/blk-mq.c > @@ -1678,6 +1678,10 @@ static void blk_mq_exit_hctx(struct request_queue *q, > blk_mq_unregister_cpu_notifier(&hctx->cpu_notifier); > blk_free_flush_queue(hctx->fq); > blk_mq_free_bitmap(&hctx->ctx_map); > + > + free_cpumask_var(hctx->cpumask); > + kfree(hctx->ctxs); > + kfree(hctx); > } > > static void blk_mq_exit_hw_queues(struct request_queue *q, > @@ -1686,12 +1690,8 @@ static void blk_mq_exit_hw_queues(struct request_queue *q, > struct blk_mq_hw_ctx *hctx; > unsigned int i; > > - queue_for_each_hw_ctx(q, hctx, i) { > + queue_for_each_hw_ctx(q, hctx, i) > blk_mq_exit_hctx(q, set, hctx, i); > - free_cpumask_var(hctx->cpumask); > - kfree(hctx->ctxs); > - kfree(hctx); > - } > > q->nr_hw_queues = 0; > } > @@ -2018,12 +2018,8 @@ static void blk_mq_realloc_hw_ctxs(struct blk_mq_tag_set *set, > set->tags[j] = NULL; > } > blk_mq_exit_hctx(q, set, hctx, j); > - free_cpumask_var(hctx->cpumask); > kobject_put(&hctx->kobj); Now this hctx->kobj will be a use-after-free since we just kfreed hctx in blk_mq_exit_hctx(). > - kfree(hctx->ctxs); > - kfree(hctx); > hctxs[j] = NULL; > - > } > } > q->nr_hw_queues = i; > -- > 1.8.3.1 > > -- > To unsubscribe from this list: send the line "unsubscribe linux-block" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html -- Omar