From mboxrd@z Thu Jan 1 00:00:00 1970 From: Tomas Bortoli Subject: Re: [PATCH] 9p: validate PDU length Date: Wed, 25 Jul 2018 12:50:36 +0200 Message-ID: References: <20180723154404.2406-1-tomasbortoli@gmail.com> <20180725041139.GB11041@nautica> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Cc: davem@davemloft.net, v9fs-developer@lists.sourceforge.net, netdev@vger.kernel.org, linux-kernel@vger.kernel.org, syzkaller@googlegroups.com To: Dominique Martinet Return-path: In-Reply-To: <20180725041139.GB11041@nautica> Content-Language: en-US Sender: linux-kernel-owner@vger.kernel.org List-Id: netdev.vger.kernel.org On 07/25/2018 06:11 AM, Dominique Martinet wrote: > Tomas Bortoli wrote on Mon, Jul 23, 2018: >> diff --git a/net/9p/client.c b/net/9p/client.c >> index 18c5271910dc..92240ccf476b 100644 >> --- a/net/9p/client.c >> +++ b/net/9p/client.c >> @@ -524,6 +525,12 @@ static int p9_check_errors(struct p9_client *c, struct p9_req_t *req) >> int ecode; >> >> err = p9_parse_header(req->rc, NULL, &type, NULL, 0); >> + if (req->rc->size >= c->msize) { > > I was looking at this again, I think it's more appropriate to use > req->rc->capacity at this point like you did in the first version of the > patch. > > I had suggested msize in the common p9_parse_header function because > that'd let us accept zc requests where the size in the pdu could be > bigger than capacity, but this isn't the case in p9_check_errors. > > If you're ok with this I'll edit your commit directly, this is less work > for me than having to check a new patch. > > Thanks, > Yes sure, just forward me the changes later. Tomas