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=-9.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham 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 29D21C04AAF for ; Mon, 20 May 2019 09:04:44 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 082042085A for ; Mon, 20 May 2019 09:04:43 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731787AbfETJEn (ORCPT ); Mon, 20 May 2019 05:04:43 -0400 Received: from szxga05-in.huawei.com ([45.249.212.191]:8218 "EHLO huawei.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1727301AbfETJEl (ORCPT ); Mon, 20 May 2019 05:04:41 -0400 Received: from DGGEMS411-HUB.china.huawei.com (unknown [172.30.72.58]) by Forcepoint Email with ESMTP id D2B7C1D3391B934B038E; Mon, 20 May 2019 17:04:38 +0800 (CST) Received: from localhost.localdomain.localdomain (10.175.113.25) by DGGEMS411-HUB.china.huawei.com (10.3.19.211) with Microsoft SMTP Server id 14.3.439.0; Mon, 20 May 2019 17:04:29 +0800 From: Kefeng Wang To: Alexander Shishkin , "Greg Kroah-Hartman" , Maxime Coquelin , Alexandre Torgue , , CC: Kefeng Wang , Hulk Robot Subject: [PATCH 1/2] hwtracing: stm: fix vfree() nonexistent vm_area Date: Mon, 20 May 2019 17:13:14 +0800 Message-ID: <20190520091315.27898-1-wangkefeng.wang@huawei.com> X-Mailer: git-send-email 2.20.1 MIME-Version: 1.0 Content-Transfer-Encoding: 7BIT Content-Type: text/plain; charset=US-ASCII X-Originating-IP: [10.175.113.25] X-CFilter-Loop: Reflected Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org If device_add() in stm_register_device() fails, stm_device_release() is called to free stm, free stm again on err_device path will trigger following warning, Trying to vfree() nonexistent vm area (0000000054b5e7bc) WARNING: CPU: 0 PID: 6004 at mm/vmalloc.c:1595 __vunmap+0x72/0x480 mm/vmalloc.c:1594 Kernel panic - not syncing: panic_on_warn set ... CPU: 0 PID: 6004 Comm: syz-executor.0 Tainted: G C 5.1.0+ #28 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1ubuntu1 04/01/2014 Call Trace: __vfree+0x2a/0x80 mm/vmalloc.c:1658 _vfree+0x49/0x70 mm/vmalloc.c:1688 stm_register_device+0x295/0x330 [stm_core] dummy_stm_init+0xfe/0x1e0 [dummy_stm] do_one_initcall+0xb9/0x3b5 init/main.c:914 do_init_module+0xe0/0x330 kernel/module.c:3468 load_module+0x38eb/0x4270 kernel/module.c:3819 __do_sys_finit_module+0x162/0x190 kernel/module.c:3909 do_syscall_64+0x72/0x2a0 arch/x86/entry/common.c:298 entry_SYSCALL_64_after_hwframe+0x49/0xbe Only free stm once if device_add() fails to fix it. Reported-by: Hulk Robot Signed-off-by: Kefeng Wang --- drivers/hwtracing/stm/core.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/drivers/hwtracing/stm/core.c b/drivers/hwtracing/stm/core.c index e55b902560de..7b2ab7b2cc4d 100644 --- a/drivers/hwtracing/stm/core.c +++ b/drivers/hwtracing/stm/core.c @@ -864,6 +864,7 @@ static void stm_device_release(struct device *dev) struct stm_device *stm = to_stm_device(dev); vfree(stm); + stm->data->stm = NULL; } int stm_register_device(struct device *parent, struct stm_data *stm_data, @@ -933,7 +934,8 @@ int stm_register_device(struct device *parent, struct stm_data *stm_data, /* matches device_initialize() above */ put_device(&stm->dev); err_free: - vfree(stm); + if (stm->data->stm) + vfree(stm); return err; } -- 2.20.1