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-next>] [day] [month] [year] [list]
Message-ID: <20210903123016.3272800-1-arseny.krasnov@kaspersky.com>
Date:   Fri, 3 Sep 2021 15:30:13 +0300
From:   Arseny Krasnov <arseny.krasnov@...persky.com>
To:     Stefan Hajnoczi <stefanha@...hat.com>,
        Stefano Garzarella <sgarzare@...hat.com>,
        "Michael S. Tsirkin" <mst@...hat.com>,
        Jason Wang <jasowang@...hat.com>,
        "David S. Miller" <davem@...emloft.net>,
        Jakub Kicinski <kuba@...nel.org>,
        Arseny Krasnov <arseny.krasnov@...persky.com>,
        Colin Ian King <colin.king@...onical.com>,
        Norbert Slusarek <nslusarek@....net>,
        Andra Paraschiv <andraprs@...zon.com>
CC:     <kvm@...r.kernel.org>, <virtualization@...ts.linux-foundation.org>,
        <netdev@...r.kernel.org>, <linux-kernel@...r.kernel.org>,
        <stsp2@...dex.ru>, <oxffffaa@...il.com>
Subject: [PATCH net-next v5 0/6] virtio/vsock: introduce MSG_EOR flag for SEQPACKET

	This patchset implements support of MSG_EOR bit for SEQPACKET
AF_VSOCK sockets over virtio transport.
	First we need to define 'messages' and 'records' like this:
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.
	Idea of patchset comes from POSIX: it says that SEQPACKET
supports record boundaries which are visible for receiver using
MSG_EOR bit. So, it looks like MSG_EOR is enough thing for SEQPACKET
and we don't need to maintain boundaries of corresponding send -
receive system calls. But, for 'sendXXX()' and 'recXXX()' POSIX says,
that all these calls operates with messages, e.g. 'sendXXX()' sends
message, while 'recXXX()' reads messages and for SEQPACKET, 'recXXX()'
must read one entire message from socket, dropping all out of size
bytes. Thus, both message boundaries and MSG_EOR bit must be supported
to follow POSIX rules.
	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.
	This patchset includes simple test for MSG_EOR.

 Arseny Krasnov(6):
  virtio/vsock: rename 'EOR' to 'EOM' bit.
  virtio/vsock: add 'VIRTIO_VSOCK_SEQ_EOR' bit.
  vhost/vsock: support MSG_EOR bit processing
  virtio/vsock: support MSG_EOR bit processing
  af_vsock: rename variables in receive loop
  vsock_test: update message bounds test for MSG_EOR

 drivers/vhost/vsock.c                   | 28 +++++++++++++----------
 include/uapi/linux/virtio_vsock.h       |  3 ++-
 net/vmw_vsock/af_vsock.c                | 10 ++++----
 net/vmw_vsock/virtio_transport_common.c | 23 ++++++++++++-------
 tools/testing/vsock/vsock_test.c        |  8 ++++++-
 5 files changed, 45 insertions(+), 27 deletions(-)

 v4 -> v5:
 - Move bitwise and out of le32_to_cpu() in 0003.

 v3 -> v4:
 - 'sendXXX()' renamed to 'send*()' in 0002- commit msg.
 - Comment about bit restore updated in 0003-.
 - 'same' renamed to 'similar' in 0003- commit msg.
 - u32 used instead of uint32_t in 0003-.

 v2 -> v3:
 - 'virtio/vsock: rename 'EOR' to 'EOM' bit.' - commit message updated.
 - 'VIRTIO_VSOCK_SEQ_EOR' bit add moved to separate patch.
 - 'vhost/vsock: support MSG_EOR bit processing' - commit message
   updated.
 - 'vhost/vsock: support MSG_EOR bit processing' - removed unneeded
   'le32_to_cpu()', because input argument was already in CPU
   endianness.

 v1 -> v2:
 - 'VIRTIO_VSOCK_SEQ_EOR' is renamed to 'VIRTIO_VSOCK_SEQ_EOM', to
   support backward compatibility.
 - use bitmask of flags to restore in vhost.c, instead of separated
   bool variable for each flag.
 - test for EAGAIN removed, as logically it is not part of this
   patchset(will be sent separately).
 - cover letter updated(added part with POSIX description).

Signed-off-by: Arseny Krasnov <arseny.krasnov@...persky.com>
-- 
2.25.1

Powered by blists - more mailing lists

Powered by Openwall GNU/*/Linux Powered by OpenVZ