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=-6.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 2504BC43603 for ; Fri, 13 Dec 2019 22:23:36 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id EF2FE22527 for ; Fri, 13 Dec 2019 22:23:35 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1576275816; bh=4iChmOKy+iWyzBUqX73EkorUxBHm0c/M19HO10x0in0=; h=Date:From:To:Cc:Subject:In-Reply-To:References:List-ID:From; b=Br13Il9NiY4dEbQJ+ihggU6VH7jMjaKhMnlOQ/HGZQqrCW/qwa2SBa+6LJh+qyetl JtPOcnZlBQJ1KZuNDoQKJ/ReUN6Pmt0n0BOL62p46lYwjUdIqM2DwpZF/GMAm4Evw4 v2KNwL2VwrGoYrgcca7F79ueQsP4Iy59TfXlNU24= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726739AbfLMWXf (ORCPT ); Fri, 13 Dec 2019 17:23:35 -0500 Received: from mail.kernel.org ([198.145.29.99]:41604 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725948AbfLMWXe (ORCPT ); Fri, 13 Dec 2019 17:23:34 -0500 Received: from localhost.localdomain (c-73-231-172-41.hsd1.ca.comcast.net [73.231.172.41]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 7C55E20706; Fri, 13 Dec 2019 22:23:33 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1576275813; bh=4iChmOKy+iWyzBUqX73EkorUxBHm0c/M19HO10x0in0=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=i4KM7W9Nv9QULJGh6tsFLMg6kACWSO3TPSt+iFvi0Lmz60OcH9UvQYZkapZjopQ6L bOgaiNRrN7wdN5Mmbr2wp6ipHtOVbzipeY8UqU1PrQLF0EPQmZFQ4R45mFjBf38I8E uhU1UDTTCEr1/BijD37EO8cG4BCMHJkEZpIVroA0= Date: Fri, 13 Dec 2019 14:23:32 -0800 From: Andrew Morton To: John Hubbard Cc: Navid Emamdoost , "Kirill A. Shutemov" , Keith Busch , , , Subject: Re: [PATCH] mm/gup: Fix memory leak in __gup_benchmark_ioctl Message-Id: <20191213142332.d7fafc243291eac302375c32@linux-foundation.org> In-Reply-To: <9a692d27-4654-f1fc-d4c5-c6efba02c8a9@nvidia.com> References: <20191211174653.4102-1-navid.emamdoost@gmail.com> <9a692d27-4654-f1fc-d4c5-c6efba02c8a9@nvidia.com> X-Mailer: Sylpheed 3.5.1 (GTK+ 2.24.31; x86_64-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, 13 Dec 2019 13:40:15 -0800 John Hubbard wrote: > On 12/11/19 9:46 AM, Navid Emamdoost wrote: > > In the implementation of __gup_benchmark_ioctl() the allocated pages > > should be released before returning in case of an invalid cmd. Release > > pages via kvfree(). > > > > Fixes: 714a3a1ebafe ("mm/gup_benchmark.c: add additional pinning methods") > > Signed-off-by: Navid Emamdoost > > --- > > mm/gup_benchmark.c | 1 + > > 1 file changed, 1 insertion(+) > > > > diff --git a/mm/gup_benchmark.c b/mm/gup_benchmark.c > > index 7dd602d7f8db..b160638f647e 100644 > > --- a/mm/gup_benchmark.c > > +++ b/mm/gup_benchmark.c > > @@ -63,6 +63,7 @@ static int __gup_benchmark_ioctl(unsigned int cmd, > > NULL); > > break; > > default: > > + kvfree(pages); > > return -1; > > } > > > > Hi, > > The patch is correct, but I would like to second Ira's request for a ret value, > and a "goto done" to use a single place to kvfree, if you don't mind. > Fair enough. And let's make it return -EINVAL rather than -1, which appears to be -EPERM. --- a/mm/gup_benchmark.c~mm-gup-fix-memory-leak-in-__gup_benchmark_ioctl-fix +++ a/mm/gup_benchmark.c @@ -26,6 +26,7 @@ static int __gup_benchmark_ioctl(unsigne unsigned long i, nr_pages, addr, next; int nr; struct page **pages; + int ret = 0; if (gup->size > ULONG_MAX) return -EINVAL; @@ -64,7 +65,8 @@ static int __gup_benchmark_ioctl(unsigne break; default: kvfree(pages); - return -1; + ret = -EINVAL; + goto out; } if (nr <= 0) @@ -86,7 +88,8 @@ static int __gup_benchmark_ioctl(unsigne gup->put_delta_usec = ktime_us_delta(end_time, start_time); kvfree(pages); - return 0; +out: + return ret; } static long gup_benchmark_ioctl(struct file *filep, unsigned int cmd, _