From: Willem de Bruijn <willemdebruijn.kernel@gmail.com>
To: Xiao Liang <shaw.leon@gmail.com>,
Willem de Bruijn <willemdebruijn.kernel@gmail.com>,
Jason Wang <jasowangio@gmail.com>
Cc: netdev@vger.kernel.org
Subject: Re: [PATCH net] tun: drop batched packets while the device is down
Date: Tue, 27 Oct 2026 10:13:27 -0400 [thread overview]
Message-ID: <willemdebruijn.kernel.979ea775ab87@gmail.com> (raw)
In-Reply-To: <20261027101830.85327-1-shaw.leon@gmail.com>
Xiao Liang wrote:
> tun_sendmsg() handles TUN_MSG_PTR batches from vhost-net by calling
> tun_xdp_one() instead of tun_get_user(). But this path does not check
> IFF_UP, allowing packets from a guest to be injected into the host
> receive path while the device is administratively down.
>
> Check IFF_UP in tun_xdp_one() before running XDP or building an skb.
> Drop the packet when the device is down, matching tun_get_user().
>
> Fixes: 043d222f93ab ("tuntap: accept an array of XDP buffs through sendmsg()")
> Signed-off-by: Xiao Liang <shaw.leon@gmail.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
next prev parent reply other threads:[~2026-10-27 14:13 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-10-27 10:18 [PATCH net] tun: drop batched packets while the device is down Xiao Liang
2026-10-27 10:21 ` netdev-bot+sinfo
2026-10-27 14:13 ` Willem de Bruijn [this message]
2026-10-29 16:30 ` patchwork-bot+netdevbpf
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=willemdebruijn.kernel.979ea775ab87@gmail.com \
--to=willemdebruijn.kernel@gmail.com \
--cc=jasowangio@gmail.com \
--cc=netdev@vger.kernel.org \
--cc=shaw.leon@gmail.com \
/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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.