From: Guillaume Nault <gnault@redhat.com>
To: Eric Dumazet <eric.dumazet@gmail.com>
Cc: "David S . Miller" <davem@davemloft.net>,
Jakub Kicinski <kuba@kernel.org>, netdev <netdev@vger.kernel.org>,
Eric Dumazet <edumazet@google.com>,
Paul Mackerras <paulus@samba.org>,
linux-ppp@vger.kernel.org, syzbot <syzkaller@googlegroups.com>
Subject: Re: [PATCH net] ppp: ensure minimum packet size in ppp_write()
Date: Wed, 5 Jan 2022 14:19:29 +0100 [thread overview]
Message-ID: <20220105131929.GA17823@pc-1.home> (raw)
In-Reply-To: <20220105114842.2380951-1-eric.dumazet@gmail.com>
On Wed, Jan 05, 2022 at 03:48:42AM -0800, Eric Dumazet wrote:
> From: Eric Dumazet <edumazet@google.com>
>
> It seems pretty clear ppp layer assumed user space
> would always be kind to provide enough data
> in their write() to a ppp device.
>
> This patch makes sure user provides at least
> 2 bytes.
>
> It adds PPP_PROTO_LEN macro that could replace
> in net-next many occurrences of hard-coded 2 value.
The PPP header can be compressed to only 1 byte, but since 2 bytes is
assumed in several parts of the code, rejecting such packets in
ppp_xmit() is probably the best we can do.
Acked-by: Guillaume Nault <gnault@redhat.com>
next prev parent reply other threads:[~2022-01-05 13:19 UTC|newest]
Thread overview: 7+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-01-05 11:48 [PATCH net] ppp: ensure minimum packet size in ppp_write() Eric Dumazet
2022-01-05 13:19 ` Guillaume Nault [this message]
2022-01-05 15:30 ` James Carlson
2022-01-05 16:29 ` Guillaume Nault
2022-01-05 16:35 ` James Carlson
2022-01-05 17:37 ` Guillaume Nault
2022-01-06 12:40 ` patchwork-bot+netdevbpf
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