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: <20210727075948.yl4w3foqa6rp4obg@steredhat>
Date:   Tue, 27 Jul 2021 09:59:48 +0200
From:   Stefano Garzarella <sgarzare@...hat.com>
To:     Arseny Krasnov <arseny.krasnov@...persky.com>
Cc:     Stefan Hajnoczi <stefanha@...hat.com>,
        "Michael S. Tsirkin" <mst@...hat.com>,
        Jason Wang <jasowang@...hat.com>,
        "David S. Miller" <davem@...emloft.net>,
        Jakub Kicinski <kuba@...nel.org>,
        Colin Ian King <colin.king@...onical.com>,
        Andra Paraschiv <andraprs@...zon.com>,
        Norbert Slusarek <nslusarek@....net>, kvm@...r.kernel.org,
        virtualization@...ts.linux-foundation.org, netdev@...r.kernel.org,
        linux-kernel@...r.kernel.org, oxffffaa@...il.com
Subject: Re: [RFC PATCH v1 0/7] virtio/vsock: introduce MSG_EOR flag for
 SEQPACKET

On Mon, Jul 26, 2021 at 07:31:33PM +0300, Arseny Krasnov wrote:
>	This patchset implements support of MSG_EOR bit for SEQPACKET
>AF_VSOCK sockets over virtio transport.
>	Idea is to distinguish concepts of 'messages' and 'records'.
>Message is result of sending calls: 'write()', 'send()', 'sendmsg()'
>etc. It has fixed maximum length, and it bounds are visible using
>return from receive calls: 'read()', 'recv()', 'recvmsg()' etc.
>Current implementation based on message definition above.
>	Record has unlimited length, it consists of multiple message,
>and bounds of record are visible via MSG_EOR flag returned from
>'recvmsg()' call. Sender passes MSG_EOR to sending system call and
>receiver will see MSG_EOR when corresponding message will be processed.
>	To support MSG_EOR new bit was added along with existing
>'VIRTIO_VSOCK_SEQ_EOR': 'VIRTIO_VSOCK_SEQ_EOM'(end-of-message) - now it
>works in the same way as 'VIRTIO_VSOCK_SEQ_EOR'. But 'VIRTIO_VSOCK_SEQ_EOR'
>is used to mark 'MSG_EOR' bit passed from userspace.

At this point it's probably better to rename the old flag, so we stay 
compatible.

What happens if one of the two peers does not support MSG_EOR handling, 
while the other does?

I'll do a closer review in the next few days.

Thanks,
Stefano

Powered by blists - more mailing lists

Powered by Openwall GNU/*/Linux Powered by OpenVZ