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=-6.6 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, 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 C450AC47255 for ; Mon, 11 May 2020 21:50:13 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 9AE8A2070B for ; Mon, 11 May 2020 21:50:13 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="Ba5c2U5i" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726950AbgEKVuM (ORCPT ); Mon, 11 May 2020 17:50:12 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:51984 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S1725860AbgEKVuM (ORCPT ); Mon, 11 May 2020 17:50:12 -0400 Received: from mail-io1-xd41.google.com (mail-io1-xd41.google.com [IPv6:2607:f8b0:4864:20::d41]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 51B9FC061A0C for ; Mon, 11 May 2020 14:50:12 -0700 (PDT) Received: by mail-io1-xd41.google.com with SMTP id i19so11606846ioh.12 for ; Mon, 11 May 2020 14:50:12 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=30OBEUef85m/ckhkASd0DpFRvKSiINQKGJMeze9kTy0=; b=Ba5c2U5iI75Br2YzOpt0q4NQjCS14rKxUGorMjadU4DgW1qTJq3Iyc4NoW7b5wADFi 33sHbejqVvHEAYKZj3+Dp7YKKy4fNJ0DM4fFi5+EPpd7Qvasyqbq1qV1YEo4l1NIEjjs Lc7ZVjVDHjzgO95qhCtYxd+JZv5S8kCOto76bX4/8IxR5U/ugC+QsLnr43mli9l6SNln riiokyMgevwIcF73XUXVEgRM6Er7wHGWR0i/l3g1m1d1c3Xd2f21FVLM/txbG3O/+MP1 UNGCzYX7OpiRaMQC2fpSeMfQjGd8gIsANIVnBOpXh6WwgxQYhmcJ5gzMzv4ylmHIcJME jrRA== 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=30OBEUef85m/ckhkASd0DpFRvKSiINQKGJMeze9kTy0=; b=IFXDprSSmNtKHYoqrtIJBibreOGUO2bDErY81/vG9LsAC1rxFu89DY8cq97ABaqHHq rJRUXXMzzkNGJRxtGtcNjWwIHifBTDOzkwJNwohrOYPFkkNAlZ3VvG1SC1XrK57wFxRm j0t/tEz2O2OyyacPPgHOnsQGz5MobKuu2DWGtEKknjPQ3BZdPNAMW+uELoA+NtLzGh5L WJagCges/k+nGwrDQx5yTiZS82njV9iD3oMmaBrkoxPmws6Kx5hQu5s34hOSK958uLai 2btkt9JwI5+WkJEvckomYH8X93SOUkjiUb8/EsJEJTDFls/nGFRbmIy4TIqu0gHfyhbh YDHg== X-Gm-Message-State: AGi0PuZF1M5umBbhDvkOVbzMYciR/tizD615nfVM522fI90F1guXionH FBdruRsa8M5Iit7SZKbcTeiXYB9YyGzpzXKsYjs= X-Google-Smtp-Source: APiQypJDYCUWqulxNR6khHuPzKCs4htOkq7OUmS8hihuk9/7nwxfPuZPX1CAOa3/504mNwcafL+8CbcpZCyCUl9saww= X-Received: by 2002:a5e:840d:: with SMTP id h13mr7377001ioj.64.1589233810705; Mon, 11 May 2020 14:50:10 -0700 (PDT) MIME-Version: 1.0 References: <20200511180227.215152-1-fabf@skynet.be> In-Reply-To: <20200511180227.215152-1-fabf@skynet.be> From: Amir Goldstein Date: Tue, 12 May 2020 00:49:58 +0300 Message-ID: Subject: Re: [PATCH 7/9 linux-next] fanotify: don't write with zero size To: Fabian Frederick Cc: Jan Kara , linux-fsdevel Content-Type: text/plain; charset="UTF-8" Sender: linux-fsdevel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org On Mon, May 11, 2020 at 9:02 PM Fabian Frederick wrote: > > check count in fanotify_write() and return -EINVAL when 0 > > Signed-off-by: Fabian Frederick > --- > fs/notify/fanotify/fanotify_user.c | 3 +++ > 1 file changed, 3 insertions(+) > > diff --git a/fs/notify/fanotify/fanotify_user.c b/fs/notify/fanotify/fanotify_user.c > index 02a314acc757..6e19dacb2475 100644 > --- a/fs/notify/fanotify/fanotify_user.c > +++ b/fs/notify/fanotify/fanotify_user.c > @@ -485,6 +485,9 @@ static ssize_t fanotify_write(struct file *file, const char __user *buf, size_t > if (!IS_ENABLED(CONFIG_FANOTIFY_ACCESS_PERMISSIONS)) > return -EINVAL; > > + if (!count) > + return -EINVAL; > + Maybe even (count < sizeof(response)) ? > group = file->private_data; > > if (count > sizeof(response)) > -- > 2.26.2 >