From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Miller Subject: Re: [PATCH v2] ethtool: do not vzalloc(0) on registers dump Date: Fri, 03 Feb 2017 11:11:52 -0500 (EST) Message-ID: <20170203.111152.2232032272459625954.davem@davemloft.net> References: <1486038730-9469-1-git-send-email-sgruszka@redhat.com> Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit Cc: netdev@vger.kernel.org, ben@decadent.org.uk To: sgruszka@redhat.com Return-path: Received: from shards.monkeyblade.net ([184.105.139.130]:38232 "EHLO shards.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750851AbdBCQLy (ORCPT ); Fri, 3 Feb 2017 11:11:54 -0500 In-Reply-To: <1486038730-9469-1-git-send-email-sgruszka@redhat.com> Sender: netdev-owner@vger.kernel.org List-ID: From: Stanislaw Gruszka Date: Thu, 2 Feb 2017 13:32:10 +0100 > If ->get_regs_len() callback return 0, we allocate 0 bytes of memory, > what print ugly warning in dmesg, which can be found further below. > > This happen on mac80211 devices where ieee80211_get_regs_len() just > return 0 and driver only fills ethtool_regs structure and actually > do not provide any dump. However I assume this can happen on other > drivers i.e. when for some devices driver provide regs dump and for > others do not. Hence preventing to to print warning in ethtool code > seems to be reasonable. ... > Signed-off-by: Stanislaw Gruszka > --- > v1 -> v2: nullify regbuf to avoid using uninitialized variable in line: > if (regbuf && copy_to_user(useraddr, regbuf, regs.len)) Applied, thanks.