From mboxrd@z Thu Jan 1 00:00:00 1970 From: Ben Hutchings Subject: Re: [PATCH] net: clear heap allocation for ETHTOOL_GRXCLSRLALL Date: Thu, 07 Oct 2010 21:28:58 +0100 Message-ID: <1286483338.2271.34.camel@achroite.uk.solarflarecom.com> References: <20101007200348.GA6038@outflux.net> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit Cc: linux-kernel@vger.kernel.org, "David S. Miller" , Jeff Garzik , Jeff Kirsher , Peter P Waskiewicz Jr , netdev@vger.kernel.org To: Kees Cook Return-path: In-Reply-To: <20101007200348.GA6038@outflux.net> Sender: linux-kernel-owner@vger.kernel.org List-Id: netdev.vger.kernel.org On Thu, 2010-10-07 at 13:03 -0700, Kees Cook wrote: > Calling ETHTOOL_GRXCLSRLALL with a large rule_cnt will allocate kernel > heap without clearing it. For the one driver (niu) that implements it, > it will leave the unused portion of heap unchanged and copy the full > contents back to userspace. > > Cc: stable@kernel.org > Signed-off-by: Kees Cook Acked-by: Ben Hutchings Should have spotted this myself. :-( Ben. > --- > net/core/ethtool.c | 2 +- > 1 files changed, 1 insertions(+), 1 deletions(-) > > diff --git a/net/core/ethtool.c b/net/core/ethtool.c > index 7a85367..4016ac6 100644 > --- a/net/core/ethtool.c > +++ b/net/core/ethtool.c > @@ -348,7 +348,7 @@ static noinline_for_stack int ethtool_get_rxnfc(struct net_device *dev, > if (info.cmd == ETHTOOL_GRXCLSRLALL) { > if (info.rule_cnt > 0) { > if (info.rule_cnt <= KMALLOC_MAX_SIZE / sizeof(u32)) > - rule_buf = kmalloc(info.rule_cnt * sizeof(u32), > + rule_buf = kzalloc(info.rule_cnt * sizeof(u32), > GFP_USER); > if (!rule_buf) > return -ENOMEM; > -- > 1.7.1 > -- Ben Hutchings, Senior Software Engineer, Solarflare Communications Not speaking for my employer; that's the marketing department's job. They asked us to note that Solarflare product names are trademarked.