From: "Alexei Starovoitov" <alexei.starovoitov@gmail.com>
To: "Ren Wei" <weir@nebusec.ai>, <bpf@vger.kernel.org>,
<netdev@vger.kernel.org>
Cc: <daniel@iogearbox.net>, <john.fastabend@gmail.com>,
<sdf@fomichev.me>, <martin.lau@linux.dev>, <andrii@kernel.org>,
<eddyz87@gmail.com>, <memxor@gmail.com>, <song@kernel.org>,
<yonghong.song@linux.dev>, <jolsa@kernel.org>,
<emil@etsalapatis.com>, <ihor.solodrai@linux.dev>,
<davem@davemloft.net>, <edumazet@google.com>, <kuba@kernel.org>,
<pabeni@redhat.com>, <horms@kernel.org>, <m.xhonneux@gmail.com>,
<dlebrun@google.com>, <vega@nebusec.ai>, <rakukuip@gmail.com>
Subject: Re: [PATCH 1/1] bpf: fix TOCTOU in IPv6 SRH encapsulation
Date: Thu, 17 Sep 2026 16:59:55 +0000 [thread overview]
Message-ID: <DLHR2X1P3BTT.HK3TEMB89P28@gmail.com> (raw)
In-Reply-To: <20260917163408.252431-1-weir@nebusec.ai>
On Fri, Sep 18, 2026 at 12:33 AM Ren Wei <weir@nebusec.ai> wrote:
> @@ -6706,16 +6706,22 @@ static const struct bpf_func_proto bpf_xdp_check_mtu_proto = {
> #if IS_ENABLED(CONFIG_IPV6_SEG6_BPF)
> static int bpf_push_seg6_encap(struct sk_buff *skb, u32 type, void *hdr, u32 len)
> {
> - int err;
> - struct ipv6_sr_hdr *srh = (struct ipv6_sr_hdr *)hdr;
> + struct ipv6_sr_hdr *srh;
> + int err = -EINVAL;
> +
> + srh = kmemdup(hdr, len, GFP_ATOMIC);
> + if (!srh)
> + return -ENOMEM;
>
> if (!seg6_validate_srh(srh, len, false))
> - return -EINVAL;
> + goto out;
Sorry. This TOCTOU issue applies to everything.
Patching it in one spot doesn't help.
pw-bot: cr
prev parent reply other threads:[~2026-09-17 16:59 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-09-17 16:33 [PATCH 0/1] bpf: fix TOCTOU in IPv6 SRH encapsulation Ren Wei
2026-09-17 16:33 ` [PATCH 1/1] " Ren Wei
2026-09-17 16:59 ` Alexei Starovoitov [this message]
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=DLHR2X1P3BTT.HK3TEMB89P28@gmail.com \
--to=alexei.starovoitov@gmail.com \
--cc=andrii@kernel.org \
--cc=bpf@vger.kernel.org \
--cc=daniel@iogearbox.net \
--cc=davem@davemloft.net \
--cc=dlebrun@google.com \
--cc=eddyz87@gmail.com \
--cc=edumazet@google.com \
--cc=emil@etsalapatis.com \
--cc=horms@kernel.org \
--cc=ihor.solodrai@linux.dev \
--cc=john.fastabend@gmail.com \
--cc=jolsa@kernel.org \
--cc=kuba@kernel.org \
--cc=m.xhonneux@gmail.com \
--cc=martin.lau@linux.dev \
--cc=memxor@gmail.com \
--cc=netdev@vger.kernel.org \
--cc=pabeni@redhat.com \
--cc=rakukuip@gmail.com \
--cc=sdf@fomichev.me \
--cc=song@kernel.org \
--cc=vega@nebusec.ai \
--cc=weir@nebusec.ai \
--cc=yonghong.song@linux.dev \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox