netdev - Re: [PATCH] bpf, sockmap: Do not read sk_receive_queue in tcp_bpf

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: <616d7c5aa492a_1eb12084b@john-XPS-13-9370.notmuch>
Date:   Mon, 18 Oct 2021 06:53:30 -0700
From:   John Fastabend <john.fastabend@...il.com>
To:     Jakub Sitnicki <jakub@...udflare.com>,
        Liu Jian <liujian56@...wei.com>
Cc:     john.fastabend@...il.com, daniel@...earbox.net, lmb@...udflare.com,
        edumazet@...gle.com, davem@...emloft.net, kuba@...nel.org,
        yoshfuji@...ux-ipv6.org, dsahern@...nel.org, ast@...nel.org,
        andrii@...nel.org, kafai@...com, songliubraving@...com, yhs@...com,
        kpsingh@...nel.org, netdev@...r.kernel.org, bpf@...r.kernel.org
Subject: Re: [PATCH] bpf, sockmap: Do not read sk_receive_queue in
 tcp_bpf_recvmsg if strparser enabled

Jakub Sitnicki wrote:
> On Fri, Oct 15, 2021 at 10:01 AM CEST, Liu Jian wrote:
> > If the strparser function of sk is turned on, all received data needs to
> > be processed by strparser first.
> >
> > Fixes: 604326b41a6fb ("bpf, sockmap: convert to generic sk_msg interface")
> > Signed-off-by: Liu Jian <liujian56@...wei.com>
> > ---
> 
> [...]
> 
> >  net/core/skmsg.c      | 5 +++++
> >  net/ipv4/tcp_bpf.c    | 9 ++++++---
> >  3 files changed, 17 insertions(+), 3 deletions(-)
> >
> > diff --git a/include/linux/skmsg.h b/include/linux/skmsg.h
> > index 94e2a1f6e58d..25e92dff04aa 100644
> > --- a/include/linux/skmsg.h
> > +++ b/include/linux/skmsg.h
> > @@ -390,6 +390,7 @@ void sk_psock_stop(struct sk_psock *psock, bool wait);
> >  int sk_psock_init_strp(struct sock *sk, struct sk_psock *psock);
> >  void sk_psock_start_strp(struct sock *sk, struct sk_psock *psock);
> >  void sk_psock_stop_strp(struct sock *sk, struct sk_psock *psock);
> > +bool sk_psock_strparser_started(struct sock *sk);
> >  #else
> >  static inline int sk_psock_init_strp(struct sock *sk, struct sk_psock *psock)
> >  {
> > @@ -403,6 +404,11 @@ static inline void sk_psock_start_strp(struct sock *sk, struct sk_psock *psock)
> >  static inline void sk_psock_stop_strp(struct sock *sk, struct sk_psock *psock)
> >  {
> >  }
> > +
> > +static inline bool sk_psock_strparser_started(struct sock *sk)
> > +{
> > +	return false;
> > +}
> >  #endif
> >  
> >  void sk_psock_start_verdict(struct sock *sk, struct sk_psock *psock);
> > diff --git a/net/core/skmsg.c b/net/core/skmsg.c
> > index e85b7f8491b9..dd64ef854f3e 100644
> > --- a/net/core/skmsg.c
> > +++ b/net/core/skmsg.c
> > @@ -1105,6 +1105,11 @@ void sk_psock_start_strp(struct sock *sk, struct sk_psock *psock)
> >  	sk->sk_write_space = sk_psock_write_space;
> >  }
> >  
> > +bool sk_psock_strparser_started(struct sock *sk)
> > +{
> > +	return sk->sk_data_ready == sk_psock_strp_data_ready;
> 
> What if kTLS is configured on the socket? I think this check won't work then.

Liu, did you see this. I think its a bit cleaner, avoids the extra parser
check in hotpath, and should solve the issue?

https://patchwork.kernel.org/project/netdevbpf/patch/20211011191647.418704-3-john.fastabend@gmail.com/

I think it should also address Jakub's concern.

Thanks,
John

> 
> > +}
> > +
> >  void sk_psock_stop_strp(struct sock *sk, struct sk_psock *psock)
> >  {
> >  	if (!psock->saved_data_ready)
> 
> [...]