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=-7.1 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS 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 7E854C46470 for ; Mon, 3 Jun 2019 13:48:48 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 57C7E27CF2 for ; Mon, 3 Jun 2019 13:48:48 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=linaro.org header.i=@linaro.org header.b="gAx0FdT7" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728585AbfFCNsr (ORCPT ); Mon, 3 Jun 2019 09:48:47 -0400 Received: from mail-ua1-f66.google.com ([209.85.222.66]:46084 "EHLO mail-ua1-f66.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727645AbfFCNsr (ORCPT ); Mon, 3 Jun 2019 09:48:47 -0400 Received: by mail-ua1-f66.google.com with SMTP id a95so6454759uaa.13 for ; Mon, 03 Jun 2019 06:48:46 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=dAX0xjkGcEXxKUF7vZFHxjTqN+8GO7j4+KMf4Q9seNI=; b=gAx0FdT7BZTU+CsokwfA7qZGL1MGYSitF1l72RSO64zJk2c5vfROnKaJ+XeXLRIBJc tsOyEMdeEDBo5OHm72bMnlUatjj++mbq6DzEdktY62SJ09UwgexFJ116A//3MaPqlGDa 7ry6f/s9ItrPTLjmX7qC3t50vTQ78DTE9QmKMibO5gh/yjZR42HGRhjyKOMG0avzhhzV UFYYXQCAg3BwOz2YhE4Dr2ArJSzoPE2UrANkB+5r+oeZ2iuMG6fCdfkRpdyfFwVRx9s8 7hwP1dKKOBD730KZXoYwwHy755KrYdgSCW1jks5DtXeg5I2Go3MCBr3byemj9IlwftuL GgZw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=dAX0xjkGcEXxKUF7vZFHxjTqN+8GO7j4+KMf4Q9seNI=; b=CGeN7g0eh29PvU4sLYc9okYln88zgQEQIQ97vh15PPKqzmz5zcFpmU2FhKQSgi6q/M thMjMYOjbTG8VjDpSKezmB/65jJedN/QargM2HPBvjDPYDI8/BBw36wnStgIJbKqy+8T U1MR0hDKLqhrZi0Qhcd5+Rlo1KBT4G4f790vF/ICTs4dWnzVJTmay92cINsZwEX+JUGM IzmSBaHgzmOA8mvrSj+/h+AtSqurbCBtfQOKtYSbGowwwfZW2znqLMp92pEA0F9oN3SV 4GdWS1Yyc1K8YI9zSCAcN0AlpON+MDREs4qkzbMOGQRwQwnKvZw031IewB4u9Rlq37gx yziQ== X-Gm-Message-State: APjAAAXshyosydw7Tx/qpfLCUi3yajNVqMivGo/XwqdSEdWmS2nEQ4jM 414mAQ2j1FD0zeY4mExqeDMFBQO+3me+FTgmsG5olg== X-Google-Smtp-Source: APXvYqzzczFhoWvx3KPDbwmQwr9gLyMfPLnT1ZWU+Mk/3rKi5dvNkbvECWmDbfWjtexLy1Xw4xZku3AK9U0Z0IPty8M= X-Received: by 2002:ab0:2b8f:: with SMTP id q15mr12844791uar.104.1559569726120; Mon, 03 Jun 2019 06:48:46 -0700 (PDT) MIME-Version: 1.0 References: <20190515143725.18872-1-wanghai26@huawei.com> In-Reply-To: <20190515143725.18872-1-wanghai26@huawei.com> From: Ulf Hansson Date: Mon, 3 Jun 2019 15:48:09 +0200 Message-ID: Subject: Re: [PATCH] memstick: Fix error cleanup path of memstick_init To: Wang Hai Cc: Maxim Levitsky , Alex Dubov , Kai Heng Feng , "linux-mmc@vger.kernel.org" , Linux Kernel Mailing List Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, 15 May 2019 at 16:39, Wang Hai wrote: > > If bus_register fails. On its error handling path, it has cleaned up > what it has done. There is no need to call bus_unregister again. > Otherwise, if bus_unregister is called, issues such as null-ptr-deref > will arise. > > Syzkaller report this: > > kobject_add_internal failed for memstick (error: -12 parent: bus) > BUG: KASAN: null-ptr-deref in sysfs_remove_file_ns+0x1b/0x40 fs/sysfs/file.c:467 > Read of size 8 at addr 0000000000000078 by task syz-executor.0/4460 > > Call Trace: > __dump_stack lib/dump_stack.c:77 [inline] > dump_stack+0xa9/0x10e lib/dump_stack.c:113 > __kasan_report+0x171/0x18d mm/kasan/report.c:321 > kasan_report+0xe/0x20 mm/kasan/common.c:614 > sysfs_remove_file_ns+0x1b/0x40 fs/sysfs/file.c:467 > sysfs_remove_file include/linux/sysfs.h:519 [inline] > bus_remove_file+0x6c/0x90 drivers/base/bus.c:145 > remove_probe_files drivers/base/bus.c:599 [inline] > bus_unregister+0x6e/0x100 drivers/base/bus.c:916 ? 0xffffffffc1590000 > memstick_init+0x7a/0x1000 [memstick] > 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 > > Fixes: baf8532a147d ("memstick: initial commit for Sony MemoryStick support") > Reported-by: Hulk Robot > Signed-off-by: Wang Hai Applied for next, thanks! Kind regards Uffe > --- > drivers/memstick/core/memstick.c | 13 +++++++++---- > 1 file changed, 9 insertions(+), 4 deletions(-) > > diff --git a/drivers/memstick/core/memstick.c b/drivers/memstick/core/memstick.c > index 1246d69ba187..b1564cacd19e 100644 > --- a/drivers/memstick/core/memstick.c > +++ b/drivers/memstick/core/memstick.c > @@ -629,13 +629,18 @@ static int __init memstick_init(void) > return -ENOMEM; > > rc = bus_register(&memstick_bus_type); > - if (!rc) > - rc = class_register(&memstick_host_class); > + if (rc) > + goto error_destroy_workqueue; > > - if (!rc) > - return 0; > + rc = class_register(&memstick_host_class); > + if (rc) > + goto error_bus_unregister; > + > + return 0; > > +error_bus_unregister: > bus_unregister(&memstick_bus_type); > +error_destroy_workqueue: > destroy_workqueue(workqueue); > > return rc; > -- > 2.17.1 > >