Received: by 2002:a25:4158:0:0:0:0:0 with SMTP id o85csp5018444yba; Tue, 30 Apr 2019 07:57:23 -0700 (PDT) X-Google-Smtp-Source: APXvYqzsepD2dEs0UbaGyXTKC72ggHst4JA1KqQ6dIZMOQHCiwWT3sJCGzTMflQZeesVOq2gBepe X-Received: by 2002:a63:f24f:: with SMTP id d15mr67368113pgk.410.1556636243855; Tue, 30 Apr 2019 07:57:23 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1556636243; cv=none; d=google.com; s=arc-20160816; b=Dti8z+vRFgEDelmwXbjRypVlS+HymBytQWfyESq9ThSOfi+/hBX/qm/wn3Nnu8BX0t YvcLfEPC1XA1/kMGh+AtVQpZluqGS9wmJ9IUiM+5WxywltatOFV5zTcHDaVyNZDDoMag nko9CN24uhTATp4G0n+hNuBJi7EnSIWbKwbSmkajJ3FIHYSxTzCVrkxZdstQrGTxVxKe pWQyhyzJJWkjpiM+LRdz2qI6zgNQF3GKlkx+bNv3vnFbv+iUqm3rvCkBULX1RK3ClsyN 0xgxUuchnyDqDxil7AKz2MiLbaw1ZnyZV7W3yzJjvIWSqFcXo+Av7Qoo2aYaYvl69yvH WnJg== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:sender:user-agent:in-reply-to :content-disposition:mime-version:references:message-id:subject:cc :to:from:date; bh=b4VypoBxcaevrMN30F16IL6WByulaZjjQi7LwgVzgv8=; b=h0rhO09F84ZCzdeyXCpqbxdad2eGQkaZO0VOh6Kyasb/Hjw6ZvRsDxcn6zHwgMCo/O UtxmBGOFnPRMoU0mAibDqq38bt/5wKWdW/T4ibCt6j7V3Kz6HytXqUmIJp3W0GA50lBM DArsavOXHDPUYMEftWzW0bsdidXDfR4hXmfkznH5E/LJ7MJAHfkYIiguP+H35PPrf4by moMPwlbtuL4yJ9IRJlxefQ2c+o5oVZHopScZGM+O69QsUATUcrlK8r6iJGSFeZJPbJAJ U1sWRSkByEcciRKgfR9h5RtSTqNDWYFTXzctrY3t6c3n9gbC6wIg7x9mBv29psDpL0CI y7Lg== ARC-Authentication-Results: i=1; mx.google.com; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Return-Path: Received: from vger.kernel.org (vger.kernel.org. [209.132.180.67]) by mx.google.com with ESMTP id r77si26535644pgr.140.2019.04.30.07.57.07; Tue, 30 Apr 2019 07:57:23 -0700 (PDT) Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67; Authentication-Results: mx.google.com; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726400AbfD3O4P (ORCPT + 99 others); Tue, 30 Apr 2019 10:56:15 -0400 Received: from mx2.suse.de ([195.135.220.15]:56398 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726053AbfD3O4O (ORCPT ); Tue, 30 Apr 2019 10:56:14 -0400 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx1.suse.de (Postfix) with ESMTP id 9FA9AABE1; Tue, 30 Apr 2019 14:56:13 +0000 (UTC) Date: Tue, 30 Apr 2019 16:56:13 +0200 From: Petr Mladek To: "Tobin C. Harding" Cc: Josh Poimboeuf , Jiri Kosina , Miroslav Benes , Greg Kroah-Hartman , Joe Lawrence , live-patching@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 1/2] livepatch: Fix kobject memleak Message-ID: <20190430145613.7tokgyqjsuxlyh2g@pathway.suse.cz> References: <20190430001534.26246-1-tobin@kernel.org> <20190430001534.26246-2-tobin@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190430001534.26246-2-tobin@kernel.org> User-Agent: NeoMutt/20170912 (1.9.0) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue 2019-04-30 10:15:33, Tobin C. Harding wrote: > Currently error return from kobject_init_and_add() is not followed by a > call to kobject_put(). This means there is a memory leak. I see, the ref count is always initialized to 1 via: + kobject_init_and_add() + kobject_init() + kobject_init_internal() + kref_init() > Signed-off-by: Tobin C. Harding > --- > kernel/livepatch/core.c | 12 +++++++++--- > 1 file changed, 9 insertions(+), 3 deletions(-) > > diff --git a/kernel/livepatch/core.c b/kernel/livepatch/core.c > index eb0ee10a1981..98a7bec41faa 100644 > --- a/kernel/livepatch/core.c > +++ b/kernel/livepatch/core.c > @@ -727,7 +727,9 @@ static int klp_init_func(struct klp_object *obj, struct klp_func *func) > ret = kobject_init_and_add(&func->kobj, &klp_ktype_func, > &obj->kobj, "%s,%lu", func->old_name, > func->old_sympos ? func->old_sympos : 1); > - if (!ret) > + if (ret) > + kobject_put(&func->kobj); > + else > func->kobj_added = true; We could actually get rid of the custom kobj_added. Intead, we could check for kobj->state_initialized in the various klp_free* functions. Best Regards, Petr