netdev - Re: [MPTCP] [PATCH net-next v2 2/4] mptcp: refactor token container

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]

Date:   Fri, 26 Jun 2020 14:25:19 -0700 (PDT)
From:   Mat Martineau <mathew.j.martineau@...ux.intel.com>
To:     Paolo Abeni <pabeni@...hat.com>
cc:     netdev@...r.kernel.org, "David S. Miller" <davem@...emloft.net>,
        Jakub Kicinski <kuba@...nel.org>, mptcp@...ts.01.org,
        Eric Dumazet <edumazet@...gle.com>
Subject: Re: [MPTCP] [PATCH net-next v2 2/4] mptcp: refactor token
 container

On Fri, 26 Jun 2020, Paolo Abeni wrote:

> Replace the radix tree with a hash table allocated
> at boot time. The radix tree has some shortcoming:
> a single lock is contented by all the mptcp operation,
> the lookup currently use such lock, and traversing
> all the items would require a lock, too.
>
> With hash table instead we trade a little memory to
> address all the above - a per bucket lock is used.
>
> To hash the MPTCP sockets, we re-use the msk' sk_node
> entry: the MPTCP sockets are never hashed by the stack.
> Replace the existing hash proto callbacks with a dummy
> implementation, annotating the above constraint.
>
> Additionally refactor the token creation to code to:
>
> - limit the number of consecutive attempts to a fixed
> maximum. Hitting a hash bucket with a long chain is
> considered a failed attempt
>
> - accept() no longer can fail to token management.
>
> - if token creation fails at connect() time, we do
> fallback to TCP (before the connection was closed)
>
> v1 -> v2:
> - fix "no newline at end of file" - Jakub
>
> Signed-off-by: Paolo Abeni <pabeni@...hat.com>
> ---
> net/mptcp/protocol.c |  45 ++++---
> net/mptcp/protocol.h |  14 ++-
> net/mptcp/subflow.c  |  19 ++-
> net/mptcp/token.c    | 271 ++++++++++++++++++++++++++++++-------------
> 4 files changed, 236 insertions(+), 113 deletions(-)

Reviewed-by: Mat Martineau <mathew.j.martineau@...ux.intel.com>

--
Mat Martineau
Intel