netdev - Re: [PATCH bpf-next 1/7] nfp: bpf: allow source ptr type be map ptr in memcpy optimization

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: <CAPhsuW4yqanLp6WEYihwMwKny8VxZQTa3G-+nOLu_e4peokNGQ@mail.gmail.com>
Date:   Mon, 25 Jun 2018 22:50:04 -0700
From:   Song Liu <liu.song.a23@...il.com>
To:     Jakub Kicinski <jakub.kicinski@...ronome.com>
Cc:     Alexei Starovoitov <alexei.starovoitov@...il.com>,
        Daniel Borkmann <daniel@...earbox.net>,
        oss-drivers@...ronome.com, Networking <netdev@...r.kernel.org>,
        Jiong Wang <jiong.wang@...ronome.com>
Subject: Re: [PATCH bpf-next 1/7] nfp: bpf: allow source ptr type be map ptr
 in memcpy optimization

On Sun, Jun 24, 2018 at 8:54 PM, Jakub Kicinski
<jakub.kicinski@...ronome.com> wrote:
> From: Jiong Wang <jiong.wang@...ronome.com>
>
> Map read has been supported on NFP, this patch enables optimization for
> memcpy from map to packet.
>
> This patch also fixed one latent bug which will cause copying from
> unexpected address once memcpy for map pointer enabled.
>
> Reported-by: Mary Pham <mary.pham@...ronome.com>
> Reported-by: David Beckett <david.beckett@...ronome.com>
> Signed-off-by: Jiong Wang <jiong.wang@...ronome.com>
> Reviewed-by: Jakub Kicinski <jakub.kicinski@...ronome.com>
> ---
>  drivers/net/ethernet/netronome/nfp/bpf/jit.c | 5 +++--
>  1 file changed, 3 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/net/ethernet/netronome/nfp/bpf/jit.c b/drivers/net/ethernet/netronome/nfp/bpf/jit.c
> index 8a92088df0d7..33111739b210 100644
> --- a/drivers/net/ethernet/netronome/nfp/bpf/jit.c
> +++ b/drivers/net/ethernet/netronome/nfp/bpf/jit.c
> @@ -670,7 +670,7 @@ static int nfp_cpp_memcpy(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
>         xfer_num = round_up(len, 4) / 4;
>
>         if (src_40bit_addr)
> -               addr40_offset(nfp_prog, meta->insn.src_reg, off, &src_base,
> +               addr40_offset(nfp_prog, meta->insn.src_reg * 2, off, &src_base,
>                               &off);

Did this break other cases before this patch?

I am sorry if this is a dumb question. I don't think I fully
understand addr40_offset().

Song

>
>         /* Setup PREV_ALU fields to override memory read length. */
> @@ -3299,7 +3299,8 @@ curr_pair_is_memcpy(struct nfp_insn_meta *ld_meta,
>         if (!is_mbpf_load(ld_meta) || !is_mbpf_store(st_meta))
>                 return false;
>
> -       if (ld_meta->ptr.type != PTR_TO_PACKET)
> +       if (ld_meta->ptr.type != PTR_TO_PACKET &&
> +           ld_meta->ptr.type != PTR_TO_MAP_VALUE)
>                 return false;
>
>         if (st_meta->ptr.type != PTR_TO_PACKET)
> --
> 2.17.1
>