netdev - Re: [PATCH bpf-next] net: Don't uninstall an XDP program when none is installed

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20190613102634.18fdb910@cakuba.netronome.com>
Date:   Thu, 13 Jun 2019 10:26:34 -0700
From:   Jakub Kicinski <jakub.kicinski@...ronome.com>
To:     Björn Töpel <bjorn.topel@...il.com>
Cc:     Maxim Mikityanskiy <maximmi@...lanox.com>,
        Alexei Starovoitov <ast@...nel.org>,
        Daniel Borkmann <daniel@...earbox.net>,
        Björn Töpel 
        <bjorn.topel@...el.com>,
        "bpf@...r.kernel.org" <bpf@...r.kernel.org>,
        "netdev@...r.kernel.org" <netdev@...r.kernel.org>,
        "David S. Miller" <davem@...emloft.net>,
        Saeed Mahameed <saeedm@...lanox.com>,
        Jesper Dangaard Brouer <hawk@...nel.org>,
        John Fastabend <john.fastabend@...il.com>,
        Martin KaFai Lau <kafai@...com>,
        Song Liu <songliubraving@...com>, Yonghong Song <yhs@...com>
Subject: Re: [PATCH bpf-next] net: Don't uninstall an XDP program when none
 is installed

On Thu, 13 Jun 2019 11:04:45 +0200, Björn Töpel wrote:
> > > +     } else {
> > > +             if (!__dev_xdp_query(dev, bpf_op, query))
> > > +                     return 0;  
> >
> > This will mask the error if program is installed with different flags.
> >  
> 
> Hmm, probably missing something, but I fail to see how the error is
> being masked? This is to catch the NULL-to-NULL case early.

You're right, it shouldn't matter.