[PATCH v1 net] tcp: Don't flag tcp_sk(sk)->rx_opt.saw_unknown for TCP AO.

[PATCH v1 net] tcp: Don't flag tcp_sk(sk)->rx_opt.saw_unknown for TCP AO.

[Kuniyuki Iwashima]

When we process segments with TCP AO, we don't check it in
tcp_parse_options().  Thus, opt_rx->saw_unknown is set to 1,
which unconditionally triggers the BPF TCP option parser.

Let's avoid the unnecessary BPF invocation.

Fixes: 0a3a809089eb ("net/tcp: Verify inbound TCP-AO signed segments")
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
---
 net/ipv4/tcp_input.c | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c
index e67cbeeeb95b..77294fd5fd3e 100644
--- a/net/ipv4/tcp_input.c
+++ b/net/ipv4/tcp_input.c
@@ -4223,6 +4223,13 @@ void tcp_parse_options(const struct net *net,
 				 * checked (see tcp_v{4,6}_rcv()).
 				 */
 				break;
+#endif
+#ifdef CONFIG_TCP_AO
+			case TCPOPT_AO:
+				/* TCP AO has already been checked
+				 * (see tcp_inbound_ao_hash()).
+				 */
+				break;
 #endif
 			case TCPOPT_FASTOPEN:
 				tcp_parse_fastopen_option(
-- 
2.30.2

Re: [PATCH v1 net] tcp: Don't flag tcp_sk(sk)->rx_opt.saw_unknown for TCP AO.

[Eric Dumazet]

On Wed, Jul 3, 2024 at 5:35 AM Kuniyuki Iwashima <kuniyu@amazon.com> wrote:
>
> When we process segments with TCP AO, we don't check it in
> tcp_parse_options().  Thus, opt_rx->saw_unknown is set to 1,
> which unconditionally triggers the BPF TCP option parser.
>
> Let's avoid the unnecessary BPF invocation.
>
> Fixes: 0a3a809089eb ("net/tcp: Verify inbound TCP-AO signed segments")
> Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>

Reviewed-by: Eric Dumazet <edumazet@google.com>

Re: [PATCH v1 net] tcp: Don't flag tcp_sk(sk)->rx_opt.saw_unknown for TCP AO.

[Dmitry Safonov]

On Wed, 3 Jul 2024 at 04:35, Kuniyuki Iwashima <kuniyu@amazon.com> wrote:
>
> When we process segments with TCP AO, we don't check it in
> tcp_parse_options().  Thus, opt_rx->saw_unknown is set to 1,
> which unconditionally triggers the BPF TCP option parser.
>
> Let's avoid the unnecessary BPF invocation.
>
> Fixes: 0a3a809089eb ("net/tcp: Verify inbound TCP-AO signed segments")
> Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>

LGTM, thanks!

Acked-by: Dmitry Safonov <0x7f454c46@gmail.com>

-- 
             Dmitry

Re: [PATCH v1 net] tcp: Don't flag tcp_sk(sk)->rx_opt.saw_unknown for TCP AO.

[Paolo Abeni]

On Tue, 2024-07-02 at 20:35 -0700, Kuniyuki Iwashima wrote:
> When we process segments with TCP AO, we don't check it in
> tcp_parse_options().  Thus, opt_rx->saw_unknown is set to 1,
> which unconditionally triggers the BPF TCP option parser.
> 
> Let's avoid the unnecessary BPF invocation.
> 
> Fixes: 0a3a809089eb ("net/tcp: Verify inbound TCP-AO signed segments")
> Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
> ---
>  net/ipv4/tcp_input.c | 7 +++++++
>  1 file changed, 7 insertions(+)
> 
> diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c
> index e67cbeeeb95b..77294fd5fd3e 100644
> --- a/net/ipv4/tcp_input.c
> +++ b/net/ipv4/tcp_input.c
> @@ -4223,6 +4223,13 @@ void tcp_parse_options(const struct net *net,
>  				 * checked (see tcp_v{4,6}_rcv()).
>  				 */
>  				break;
> +#endif
> +#ifdef CONFIG_TCP_AO
> +			case TCPOPT_AO:
> +				/* TCP AO has already been checked
> +				 * (see tcp_inbound_ao_hash()).
> +				 */
> +				break;
>  #endif
>  			case TCPOPT_FASTOPEN:
>  				tcp_parse_fastopen_option(

[not strictly related to this patch] possibly even MPTCP could benefit
from a similar change, but I'm unsure if we want to add even more cases
to this statement.

Cheers,

Paolo

Re: [PATCH v1 net] tcp: Don't flag tcp_sk(sk)->rx_opt.saw_unknown for TCP AO.

[patchwork-bot+netdevbpf]

Hello:

This patch was applied to netdev/net.git (main)
by Paolo Abeni <pabeni@redhat.com>:

On Tue, 2 Jul 2024 20:35:08 -0700 you wrote:
> When we process segments with TCP AO, we don't check it in
> tcp_parse_options().  Thus, opt_rx->saw_unknown is set to 1,
> which unconditionally triggers the BPF TCP option parser.
> 
> Let's avoid the unnecessary BPF invocation.
> 
> Fixes: 0a3a809089eb ("net/tcp: Verify inbound TCP-AO signed segments")
> Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
> 
> [...]

Here is the summary with links:
  - [v1,net] tcp: Don't flag tcp_sk(sk)->rx_opt.saw_unknown for TCP AO.
    https://git.kernel.org/netdev/net/c/4b74726c01b7

You are awesome, thank you!
-- 
Deet-doot-dot, I am a bot.
https://korg.docs.kernel.org/patchwork/pwbot.html

Re: [PATCH v1 net] tcp: Don't flag tcp_sk(sk)->rx_opt.saw_unknown for TCP AO.

[Kuniyuki Iwashima]

From: Paolo Abeni <pabeni@redhat.com>
Date: Thu, 04 Jul 2024 12:05:42 +0200
> On Tue, 2024-07-02 at 20:35 -0700, Kuniyuki Iwashima wrote:
> > When we process segments with TCP AO, we don't check it in
> > tcp_parse_options().  Thus, opt_rx->saw_unknown is set to 1,
> > which unconditionally triggers the BPF TCP option parser.
> > 
> > Let's avoid the unnecessary BPF invocation.
> > 
> > Fixes: 0a3a809089eb ("net/tcp: Verify inbound TCP-AO signed segments")
> > Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
> > ---
> >  net/ipv4/tcp_input.c | 7 +++++++
> >  1 file changed, 7 insertions(+)
> > 
> > diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c
> > index e67cbeeeb95b..77294fd5fd3e 100644
> > --- a/net/ipv4/tcp_input.c
> > +++ b/net/ipv4/tcp_input.c
> > @@ -4223,6 +4223,13 @@ void tcp_parse_options(const struct net *net,
> >  				 * checked (see tcp_v{4,6}_rcv()).
> >  				 */
> >  				break;
> > +#endif
> > +#ifdef CONFIG_TCP_AO
> > +			case TCPOPT_AO:
> > +				/* TCP AO has already been checked
> > +				 * (see tcp_inbound_ao_hash()).
> > +				 */
> > +				break;
> >  #endif
> >  			case TCPOPT_FASTOPEN:
> >  				tcp_parse_fastopen_option(
> 
> [not strictly related to this patch] possibly even MPTCP could benefit
> from a similar change, but I'm unsure if we want to add even more cases
> to this statement.

Exactly, it seem no one has tried to inject/parse a new option with MPTCP.