From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-14.9 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id EE865C433E2 for ; Mon, 14 Sep 2020 17:05:07 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id B325E21D80 for ; Mon, 14 Sep 2020 17:05:07 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1600103107; bh=4wZr63C8pkIo1vI82osNj8vsoS+ubogokVn9LtJTXhw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=AHMPG4Ud8+qvgjzl65C7ew8Mw4+qIv9kHevyrQRkXWH5jI46FpquwwVr2HJ3I6JA0 KszmDLoSinGjXSg//fauYUrvG0Ls5qj89vVDeXaBvk8LREt1FfDgV3vvAmGRhZ/CHu 2Cso1W1wKfc7HPeewssd379c9HOkGDH8OLg+cKRc= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726171AbgINRFC (ORCPT ); Mon, 14 Sep 2020 13:05:02 -0400 Received: from mail.kernel.org ([198.145.29.99]:60274 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726520AbgINNF1 (ORCPT ); Mon, 14 Sep 2020 09:05:27 -0400 Received: from sasha-vm.mshome.net (c-73-47-72-35.hsd1.nh.comcast.net [73.47.72.35]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 9353B208E4; Mon, 14 Sep 2020 13:04:29 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1600088670; bh=4wZr63C8pkIo1vI82osNj8vsoS+ubogokVn9LtJTXhw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=egK+kg8ERBdgy1+vsiw6RK/j+tRXRdiK6bFYUJvqRD1WwSKJa+rIlzS1E/hMU+Yhp YQ00s8nwokJjjuA1T1bNAUMgp9LQpZ7LHbwFRFftcIpSeGciYzn9ULfy45e9R1+Ws3 nq3/rt29RISu2lvCsmLoM3UZnXIaOQfxBIkDBEPk= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Gustav Wiklander , Mark Brown , Sasha Levin , linux-spi@vger.kernel.org Subject: [PATCH AUTOSEL 5.8 26/29] spi: Fix memory leak on splited transfers Date: Mon, 14 Sep 2020 09:03:55 -0400 Message-Id: <20200914130358.1804194-26-sashal@kernel.org> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20200914130358.1804194-1-sashal@kernel.org> References: <20200914130358.1804194-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Gustav Wiklander [ Upstream commit b59a7ca15464c78ea1ba3b280cfc5ac5ece11ade ] In the prepare_message callback the bus driver has the opportunity to split a transfer into smaller chunks. spi_map_msg is done after prepare_message. Function spi_res_release releases the splited transfers in the message. Therefore spi_res_release should be called after spi_map_msg. The previous try at this was commit c9ba7a16d0f1 which released the splited transfers after spi_finalize_current_message had been called. This introduced a race since the message struct could be out of scope because the spi_sync call got completed. Fixes this leak on spi bus driver spi-bcm2835.c when transfer size is greater than 65532: Kmemleak: sg_alloc_table+0x28/0xc8 spi_map_buf+0xa4/0x300 __spi_pump_messages+0x370/0x748 __spi_sync+0x1d4/0x270 spi_sync+0x34/0x58 spi_test_execute_msg+0x60/0x340 [spi_loopback_test] spi_test_run_iter+0x548/0x578 [spi_loopback_test] spi_test_run_test+0x94/0x140 [spi_loopback_test] spi_test_run_tests+0x150/0x180 [spi_loopback_test] spi_loopback_test_probe+0x50/0xd0 [spi_loopback_test] spi_drv_probe+0x84/0xe0 Signed-off-by: Gustav Wiklander Link: https://lore.kernel.org/r/20200908151129.15915-1-gustav.wiklander@axis.com Signed-off-by: Mark Brown Signed-off-by: Sasha Levin --- drivers/spi/spi.c | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-) diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c index 5c5a95792c0d3..65ca552654794 100644 --- a/drivers/spi/spi.c +++ b/drivers/spi/spi.c @@ -1305,8 +1305,6 @@ static int spi_transfer_one_message(struct spi_controller *ctlr, if (msg->status && ctlr->handle_err) ctlr->handle_err(ctlr, msg); - spi_res_release(ctlr, msg); - spi_finalize_current_message(ctlr); return ret; @@ -1694,6 +1692,13 @@ void spi_finalize_current_message(struct spi_controller *ctlr) spi_unmap_msg(ctlr, mesg); + /* In the prepare_messages callback the spi bus has the opportunity to + * split a transfer to smaller chunks. + * Release splited transfers here since spi_map_msg is done on the + * splited transfers. + */ + spi_res_release(ctlr, mesg); + if (ctlr->cur_msg_prepared && ctlr->unprepare_message) { ret = ctlr->unprepare_message(ctlr, mesg); if (ret) { -- 2.25.1