From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751850AbaEQWwV (ORCPT ); Sat, 17 May 2014 18:52:21 -0400 Received: from mail.linux-iscsi.org ([67.23.28.174]:43240 "EHLO linux-iscsi.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751794AbaEQWwT (ORCPT ); Sat, 17 May 2014 18:52:19 -0400 Message-ID: <1400367123.16727.0.camel@haakon3.risingtidesystems.com> Subject: Re: [PATCH] target: fix memory leak on XCOPY From: "Nicholas A. Bellinger" To: Mikulas Patocka Cc: linux-scsi@vger.kernel.org, target-devel@vger.kernel.org, linux-kernel@vger.kernel.org Date: Sat, 17 May 2014 15:52:03 -0700 In-Reply-To: References: Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.4.4-1 Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sat, 2014-05-17 at 06:49 -0400, Mikulas Patocka wrote: > On each processed XCOPY command, two "kmalloc-512" memory objects are > leaked. These represent two allocations of struct xcopy_pt_cmd in > target_core_xcopy.c. > > The reason for the memory leak is that the cmd_kref field is not > initialized (thus, it is zero because the allocations were done with > kzalloc). When we decrement zero kref in target_put_sess_cmd, the result > is not zero, thus target_release_cmd_kref is not called. > > This patch fixes the bug by moving kref initialization from > target_get_sess_cmd to transport_init_se_cmd (this function is called from > target_core_xcopy.c, so it will correctly initialize cmd_kref). It can be > easily verified that all code that calls target_get_sess_cmd also calls > transport_init_se_cmd earlier, thus moving kref_init shouldn't introduce > any new problems. > > Signed-off-by: Mikulas Patocka > Cc: stable@vger.kernel.org # 3.12+ > > --- > drivers/target/target_core_transport.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > Index: linux-3.15-rc5/drivers/target/target_core_transport.c > =================================================================== > --- linux-3.15-rc5.orig/drivers/target/target_core_transport.c 2014-04-14 16:08:15.000000000 +0200 > +++ linux-3.15-rc5/drivers/target/target_core_transport.c 2014-05-16 18:24:57.000000000 +0200 > @@ -1113,6 +1113,7 @@ void transport_init_se_cmd( > init_completion(&cmd->cmd_wait_comp); > init_completion(&cmd->task_stop_comp); > spin_lock_init(&cmd->t_state_lock); > + kref_init(&cmd->cmd_kref); > cmd->transport_state = CMD_T_DEV_ACTIVE; > > cmd->se_tfo = tfo; > @@ -2357,7 +2358,6 @@ int target_get_sess_cmd(struct se_sessio > unsigned long flags; > int ret = 0; > > - kref_init(&se_cmd->cmd_kref); > /* > * Add a second kref if the fabric caller is expecting to handle > * fabric acknowledgement that requires two target_put_sess_cmd() > -- Applied. Thanks alot Mikulas! --nab