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=-15.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 80132C43461 for ; Mon, 17 May 2021 14:23:56 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 612C361992 for ; Mon, 17 May 2021 14:23:56 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239601AbhEQOY1 (ORCPT ); Mon, 17 May 2021 10:24:27 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:38094 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239175AbhEQOVF (ORCPT ); Mon, 17 May 2021 10:21:05 -0400 Received: from mail-wr1-x42e.google.com (mail-wr1-x42e.google.com [IPv6:2a00:1450:4864:20::42e]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4E82AC06123A for ; Mon, 17 May 2021 07:09:49 -0700 (PDT) Received: by mail-wr1-x42e.google.com with SMTP id p7so2826124wru.10 for ; Mon, 17 May 2021 07:09:49 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ffwll.ch; s=google; h=date:from:to:cc:subject:message-id:mail-followup-to:references :mime-version:content-disposition:in-reply-to; bh=lIOh8/w3jAFbRZR6B6qvkXxoI0bkEVRhq3CS0yvuHY4=; b=cByxw4PfXTDQI44Csx59GLW37uL7zPAYfW2WwPypM7tpQm6I9oUAKqBZ0bsF1Z7S1C ffxS/bx/9UFdCCWv19P48ruRS9S5VYwLA3sENlAR0gmuuAoDCm8Zv/64ysR2rwcb+pya a9AknJ/qQ0APAbKhC2+XhvtYxBgT4kZewdP+o= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id :mail-followup-to:references:mime-version:content-disposition :in-reply-to; bh=lIOh8/w3jAFbRZR6B6qvkXxoI0bkEVRhq3CS0yvuHY4=; b=SSpRO3NlQgX3+uk5vMikFHwrKCTUCYYo+4WPbFfwG5QaF0R05LSaIyyU0GMEZv4awG zggfTV5aQ3eeqBcQe2yoSLJkmFNPAAZ5AeBh7uVHzTiy5P4IuOLWsnt5Iin0EAuiV4JV DaQlM+VMeoAzT1oqU5Pi3LQpB7idAqVXvwvKvmBcKcEEAd33LUyw6fzj0SFP8roz45NM 7TpxPwzsM7qk2gEvLuVnd7hZr+mGUWNTJnEoYCgRyFtf3yhHrjGlxbAEOmc3+PbMPaPX gap8cq6HFdwYlKcr0AfW1BatPtHGWFtsKBULZv2IQVl/nvLb7fzimLE7wvgKwDoq2l0a mnAA== X-Gm-Message-State: AOAM530vjUrObysST74AK9KDdVTY+/RhqXhGhN2hcjI3QXkC7eA4AXVj uX2MAHOe4VFPedwyLR4Kh1N6fQ== X-Google-Smtp-Source: ABdhPJxggEzrKat8/WIdxJRJJGOuH2X6KWDEG4qPyhSVEB/a1OOQPSRz4MkApBLnYgDN4YjvvppDyg== X-Received: by 2002:a5d:43c7:: with SMTP id v7mr5997385wrr.310.1621260588142; Mon, 17 May 2021 07:09:48 -0700 (PDT) Received: from phenom.ffwll.local ([2a02:168:57f4:0:efd0:b9e5:5ae6:c2fa]) by smtp.gmail.com with ESMTPSA id t11sm17684321wrz.57.2021.05.17.07.09.47 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 17 May 2021 07:09:47 -0700 (PDT) Date: Mon, 17 May 2021 16:09:45 +0200 From: Daniel Vetter To: Hao Peng Cc: rodrigosiqueiramelo@gmail.com, melissa.srw@gmail.com, hamohammed.sa@gmail.com, daniel@ffwll.ch, airlied@linux.ie, dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] drm:vkms: Add NULL value after free function In function vkms_exit, after kfree(default_config), give specific NULL value to pointer default_config to avoid wild pointer. Message-ID: Mail-Followup-To: Hao Peng , rodrigosiqueiramelo@gmail.com, melissa.srw@gmail.com, hamohammed.sa@gmail.com, airlied@linux.ie, dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org References: <20210512115554.10431-1-penghaob@uniontech.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210512115554.10431-1-penghaob@uniontech.com> X-Operating-System: Linux phenom 5.10.32scarlett+ Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, May 12, 2021 at 07:55:54PM +0800, Hao Peng wrote: > Signed-off-by: Hao Peng > --- > drivers/gpu/drm/vkms/vkms_drv.c | 1 + > 1 file changed, 1 insertion(+) > > diff --git a/drivers/gpu/drm/vkms/vkms_drv.c b/drivers/gpu/drm/vkms/vkms_drv.c > index 2173b82606f6..6c63201db5d0 100644 > --- a/drivers/gpu/drm/vkms/vkms_drv.c > +++ b/drivers/gpu/drm/vkms/vkms_drv.c > @@ -227,6 +227,7 @@ static void __exit vkms_exit(void) > vkms_destroy(default_config); > > kfree(default_config); > + default_config = NULL; This is the last thing before the module us unloaded, which means no one can access default_config anymore. So also no point in clearing it. -Daniel > } > > module_init(vkms_init); > -- > 2.20.1 > > > -- Daniel Vetter Software Engineer, Intel Corporation http://blog.ffwll.ch