From patchwork Fri Sep 29 09:19:52 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Wolfram Sang X-Patchwork-Id: 728286 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id E7704E743FE for ; Fri, 29 Sep 2023 09:20:02 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232519AbjI2JUC (ORCPT ); Fri, 29 Sep 2023 05:20:02 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:57038 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231774AbjI2JUC (ORCPT ); Fri, 29 Sep 2023 05:20:02 -0400 Received: from mail.zeus03.de (www.zeus03.de [194.117.254.33]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 766EB1A8 for ; Fri, 29 Sep 2023 02:19:59 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d= sang-engineering.com; h=from:to:cc:subject:date:message-id :mime-version:content-transfer-encoding; s=k1; bh=CPCOX8Pk808b+b p768FKhaTdrGjFDu5eVaZMfKQbRpU=; b=TNnoYa3iv05zXfEWTwp4/pi40Du+IF 8heVnVxeXg0mIFyQeyzUJiBXjACBBOtgORflQmm6zwzViPMpb/bF5He6jTefXSpn gA3AqiR9pqbMoTBL6iqtBWkdxuAD/CSjjjz24cIXu1vwme9aYB2S8dWmG4cQyRIv oz45OCfOuYaGdQAHAcCo2PbDdDeE/scvWvao3bY6Hdv87S9gFIqPHooOuPgP6VRl uZNoAl80ATsBZEnRc3cjsyN9NY0dGmLUMxMFqRbn4E452pfc5O9vloqOcaUF10SU j8jyTjd465dXaZ0mDSfZ53dMzt2LAi1BhhGKcgaWLxDKFevh75MdFpDA== Received: (qmail 3780117 invoked from network); 29 Sep 2023 11:19:56 +0200 Received: by mail.zeus03.de with ESMTPSA (TLS_AES_256_GCM_SHA384 encrypted, authenticated); 29 Sep 2023 11:19:56 +0200 X-UD-Smtp-Session: l3s3148p1@sfOD7XsGGL0ujntX From: Wolfram Sang To: linux-renesas-soc@vger.kernel.org Cc: Yang Yingliang , Wolfram Sang , linux-i2c@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH v3] i2c: fix memleak in i2c_new_client_device() Date: Fri, 29 Sep 2023 11:19:52 +0200 Message-Id: <20230929091952.19957-1-wsa+renesas@sang-engineering.com> X-Mailer: git-send-email 2.30.2 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-i2c@vger.kernel.org Yang Yingliang reported a memleak: === I got memory leak as follows when doing fault injection test: unreferenced object 0xffff888014aec078 (size 8): comm "xrun", pid 356, jiffies 4294910619 (age 16.332s) hex dump (first 8 bytes): 31 2d 30 30 31 63 00 00 1-001c.. backtrace: [<00000000eb56c0a9>] __kmalloc_track_caller+0x1a6/0x300 [<000000000b220ea3>] kvasprintf+0xad/0x140 [<00000000b83203e5>] kvasprintf_const+0x62/0x190 [<000000002a5eab37>] kobject_set_name_vargs+0x56/0x140 [<00000000300ac279>] dev_set_name+0xb0/0xe0 [<00000000b66ebd6f>] i2c_new_client_device+0x7e4/0x9a0 If device_register() returns error in i2c_new_client_device(), the name allocated by i2c_dev_set_name() need be freed. As comment of device_register() says, it should use put_device() to give up the reference in the error path. === I think this solution is less intrusive and more robust than he originally proposed solutions, though. Reported-by: Yang Yingliang Closes: http://patchwork.ozlabs.org/project/linux-i2c/patch/20221124085448.3620240-1-yangyingliang@huawei.com/ Signed-off-by: Wolfram Sang --- Build tested only. @Yang Yingliang: I'd be happy if you could test it/comment on it. drivers/i2c/i2c-core-base.c | 13 +++++++++---- 1 file changed, 9 insertions(+), 4 deletions(-) diff --git a/drivers/i2c/i2c-core-base.c b/drivers/i2c/i2c-core-base.c index cc4a20465456..0d6172d6b808 100644 --- a/drivers/i2c/i2c-core-base.c +++ b/drivers/i2c/i2c-core-base.c @@ -931,8 +931,9 @@ int i2c_dev_irq_from_resources(const struct resource *resources, struct i2c_client * i2c_new_client_device(struct i2c_adapter *adap, struct i2c_board_info const *info) { - struct i2c_client *client; - int status; + struct i2c_client *client; + bool need_put = false; + int status; client = kzalloc(sizeof *client, GFP_KERNEL); if (!client) @@ -970,7 +971,6 @@ i2c_new_client_device(struct i2c_adapter *adap, struct i2c_board_info const *inf client->dev.fwnode = info->fwnode; device_enable_async_suspend(&client->dev); - i2c_dev_set_name(adap, client, info); if (info->swnode) { status = device_add_software_node(&client->dev, info->swnode); @@ -982,6 +982,7 @@ i2c_new_client_device(struct i2c_adapter *adap, struct i2c_board_info const *inf } } + i2c_dev_set_name(adap, client, info); status = device_register(&client->dev); if (status) goto out_remove_swnode; @@ -993,6 +994,7 @@ i2c_new_client_device(struct i2c_adapter *adap, struct i2c_board_info const *inf out_remove_swnode: device_remove_software_node(&client->dev); + need_put = true; out_err_put_of_node: of_node_put(info->of_node); out_err: @@ -1000,7 +1002,10 @@ i2c_new_client_device(struct i2c_adapter *adap, struct i2c_board_info const *inf "Failed to register i2c client %s at 0x%02x (%d)\n", client->name, client->addr, status); out_err_silent: - kfree(client); + if (need_put) + put_device(&client->dev); + else + kfree(client); return ERR_PTR(status); } EXPORT_SYMBOL_GPL(i2c_new_client_device);