linux.git/net/sctp, branch v4.11

sctp: listen on the sock only when it's state is listening or closed

2017-04-06T20:55:51+00:00

Now sctp doesn't check sock's state before listening on it. It could
even cause changing a sock with any state to become a listening sock
when doing sctp_listen.

This patch is to fix it by checking sock's state in sctp_listen, so
that it will listen on the sock with right state.

Reported-by: Andrey Konovalov 
Tested-by: Andrey Konovalov 
Signed-off-by: Xin Long 
Acked-by: Marcelo Ricardo Leitner 
Signed-off-by: David S. Miller

sctp: get sock from transport in sctp_transport_update_pmtu

2017-04-05T14:20:06+00:00

This patch is almost to revert commit 02f3d4ce9e81 ("sctp: Adjust PMTU
updates to accomodate route invalidation."). As t->asoc can't be NULL
in sctp_transport_update_pmtu, it could get sk from asoc, and no need
to pass sk into that function.

It is also to remove some duplicated codes from that function.

Signed-off-by: Xin Long 
Acked-by: Marcelo Ricardo Leitner 
Signed-off-by: David S. Miller

sctp: check for dst and pathmtu update in sctp_packet_config

2017-04-03T21:54:33+00:00

This patch is to move sctp_transport_dst_check into sctp_packet_config
from sctp_packet_transmit and add pathmtu check in sctp_packet_config.

With this fix, sctp can update dst or pathmtu before appending chunks,
which can void dropping packets in sctp_packet_transmit when dst is
obsolete or dst's mtu is changed.

This patch is also to improve some other codes in sctp_packet_config.
It updates packet max_size with gso_max_size, checks for dst and
pathmtu, and appends ecne chunk only when packet is empty and asoc
is not NULL.

It makes sctp flush work better, as we only need to set up them once
for one flush schedule. It's also safe, since asoc is NULL only when
the packet is created by sctp_ootb_pkt_new in which it just gets the
new dst, no need to do more things for it other than set packet with
transport's pathmtu.

Signed-off-by: Xin Long 
Acked-by: Marcelo Ricardo Leitner 
Acked-by: Neil Horman 
Signed-off-by: David S. Miller

sctp: use right in and out stream cnt

2017-04-02T03:12:30+00:00

Since sctp reconf was added in sctp, the real cnt of in/out stream
have not been c.sinit_max_instreams and c.sinit_num_ostreams any
more.

This patch is to replace them with stream->in/outcnt.

Signed-off-by: Xin Long 
Acked-by: Marcelo Ricardo Leitner 
Signed-off-by: David S. Miller

sctp: alloc stream info when initializing asoc

2017-03-30T18:08:47+00:00

When sending a msg without asoc established, sctp will send INIT packet
first and then enqueue chunks.

Before receiving INIT_ACK, stream info is not yet alloced. But enqueuing
chunks needs to access stream info, like out stream state and out stream
cnt.

This patch is to fix it by allocing out stream info when initializing an
asoc, allocing in stream and re-allocing out stream when processing init.

Signed-off-by: Xin Long 
Signed-off-by: David S. Miller

sctp: change to save MSG_MORE flag into assoc

2017-03-29T00:56:15+00:00

David Laight noticed the support for MSG_MORE with datamsg->force_delay
didn't really work as we expected, as the first msg with MSG_MORE set
would always block the following chunks' dequeuing.

This Patch is to rewrite it by saving the MSG_MORE flag into assoc as
David Laight suggested.

asoc->force_delay is used to save MSG_MORE flag before a msg is sent.
All chunks in queue would not be sent out if asoc->force_delay is set
by the msg with MSG_MORE flag, until a new msg without MSG_MORE flag
clears asoc->force_delay.

Note that this change would not affect the flush is generated by other
triggers, like asoc->state != ESTABLISHED, queue size > pmtu etc.

v1->v2:
  Not clear asoc->force_delay after sending the msg with MSG_MORE flag.

Fixes: 4ea0c32f5f42 ("sctp: add support for MSG_MORE")
Signed-off-by: Xin Long 
Acked-by: David Laight 
Acked-by: Marcelo Ricardo Leitner 
Signed-off-by: David S. Miller

sctp: remove useless err from sctp_association_init

2017-03-22T17:57:52+00:00

This patch is to remove the unnecessary temporary variable 'err' from
sctp_association_init.

Signed-off-by: Xin Long 
Acked-by: Neil Horman 
Signed-off-by: David S. Miller

sctp: out_qlen should be updated when pruning unsent queue

2017-03-22T01:32:36+00:00

This patch is to fix the issue that sctp_prsctp_prune_sent forgot
to update q->out_qlen when removing a chunk from unsent queue.

Fixes: 8dbdf1f5b09c ("sctp: implement prsctp PRIO policy")
Signed-off-by: Xin Long 
Acked-by: Marcelo Ricardo Leitner 
Signed-off-by: David S. Miller

sctp: remove temporary variable confirm from sctp_packet_transmit

2017-03-22T01:31:02+00:00

Commit c86a773c7802 ("sctp: add dst_pending_confirm flag") introduced
a temporary variable "confirm" in sctp_packet_transmit.

But it broke the rule that longer lines should be above shorter ones.
Besides, this variable is not necessary, so this patch is to just
remove it and use tp->dst_pending_confirm directly.

Fixes: c86a773c7802 ("sctp: add dst_pending_confirm flag")
Signed-off-by: Xin Long 
Acked-by: Neil Horman 
Signed-off-by: David S. Miller

net: Work around lockdep limitation in sockets that use sockets

2017-03-10T02:23:27+00:00

Lockdep issues a circular dependency warning when AFS issues an operation
through AF_RXRPC from a context in which the VFS/VM holds the mmap_sem.

The theory lockdep comes up with is as follows:

 (1) If the pagefault handler decides it needs to read pages from AFS, it
     calls AFS with mmap_sem held and AFS begins an AF_RXRPC call, but
     creating a call requires the socket lock:

	mmap_sem must be taken before sk_lock-AF_RXRPC

 (2) afs_open_socket() opens an AF_RXRPC socket and binds it.  rxrpc_bind()
     binds the underlying UDP socket whilst holding its socket lock.
     inet_bind() takes its own socket lock:

	sk_lock-AF_RXRPC must be taken before sk_lock-AF_INET

 (3) Reading from a TCP socket into a userspace buffer might cause a fault
     and thus cause the kernel to take the mmap_sem, but the TCP socket is
     locked whilst doing this:

	sk_lock-AF_INET must be taken before mmap_sem

However, lockdep's theory is wrong in this instance because it deals only
with lock classes and not individual locks.  The AF_INET lock in (2) isn't
really equivalent to the AF_INET lock in (3) as the former deals with a
socket entirely internal to the kernel that never sees userspace.  This is
a limitation in the design of lockdep.

Fix the general case by:

 (1) Double up all the locking keys used in sockets so that one set are
     used if the socket is created by userspace and the other set is used
     if the socket is created by the kernel.

 (2) Store the kern parameter passed to sk_alloc() in a variable in the
     sock struct (sk_kern_sock).  This informs sock_lock_init(),
     sock_init_data() and sk_clone_lock() as to the lock keys to be used.

     Note that the child created by sk_clone_lock() inherits the parent's
     kern setting.

 (3) Add a 'kern' parameter to ->accept() that is analogous to the one
     passed in to ->create() that distinguishes whether kernel_accept() or
     sys_accept4() was the caller and can be passed to sk_alloc().

     Note that a lot of accept functions merely dequeue an already
     allocated socket.  I haven't touched these as the new socket already
     exists before we get the parameter.

     Note also that there are a couple of places where I've made the accepted
     socket unconditionally kernel-based:

	irda_accept()
	rds_rcp_accept_one()
	tcp_accept_from_sock()

     because they follow a sock_create_kern() and accept off of that.

Whilst creating this, I noticed that lustre and ocfs don't create sockets
through sock_create_kern() and thus they aren't marked as for-kernel,
though they appear to be internal.  I wonder if these should do that so
that they use the new set of lock keys.

Signed-off-by: David Howells 
Signed-off-by: David S. Miller