Copy stable/10@r272459 to releng/10.1 as part of
the 10.1-RELEASE process.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

MFC r267336:

PF_BLUETOOTH protocols: skip initialization of non-virtualized globals
for non-default VNET instances.

This fixes panic on a vnet initialization when ng_btsocket is loaded.

Copy head (r256279) to stable/10 as part of the 10.0-RELEASE cycle.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

Mechanically substitute flags from historic mbuf allocator with
malloc(9) flags within sys.

Exceptions:

- sys/contrib not touched
- sys/mbuf.h edited manually

Mark all SYSCTL_NODEs static that have no corresponding SYSCTL_DECLs.

The SYSCTL_NODE macro defines a list that stores all child-elements of
that node. If there's no SYSCTL_DECL macro anywhere else, there's no
reason why it shouldn't be static.

Mark MALLOC_DEFINEs static that have no corresponding MALLOC_DECLAREs.

This means that their use is restricted to a single C file.

Fix typos - remove duplicate "the".

PR: bin/154928
Submitted by: Eitan Adler <lists at eitanadler.com>
MFC after: 3 days

Mfp4 CH=177274,177280,177284-177285,177297,177324-177325

VNET socket push back:
try to minimize the number of places where we have to switch vnets
and narrow down the time we stay switched. Add assertions to the
socket code to catch possibly unset vnets as seen in r204147.

While this reduces the number of vnet recursion in some places like
NFS, POSIX local sockets and some netgraph, .. recursions are
impossible to fix.

The current expectations are documented at the beginning of
uipc_socket.c along with the other information there.

Sponsored by: The FreeBSD Foundation
Sponsored by: CK Software GmbH
Reviewed by: jhb
Tested by: zec

Tested by: Mikolaj Golub (to.my.trociny gmail.com)
MFC after: 2 weeks

sysctl(9) cleanup checkpoint: amd64 GENERIC builds cleanly.

Commit the netgraph piece.

Rework socket upcalls to close some races with setup/teardown of upcalls.
- Each socket upcall is now invoked with the appropriate socket buffer
locked. It is not permissible to call soisconnected() with this lock
held; however, so socket upcalls now return an integer value. The two
possible values are SU_OK and SU_ISCONNECTED. If an upcall returns
SU_ISCONNECTED, then the soisconnected() will be invoked on the
socket after the socket buffer lock is dropped.
- A new API is provided for setting and clearing socket upcalls. The
API consists of soupcall_set() and soupcall_clear().
- To simplify locking, each socket buffer now has a separate upcall.
- When a socket upcall returns SU_ISCONNECTED, the upcall is cleared from
the receive socket buffer automatically. Note that a SO_SND upcall
should never return SU_ISCONNECTED.
- All this means that accept filters should now return SU_ISCONNECTED
instead of calling soisconnected() directly. They also no longer need
to explicitly clear the upcall on the new socket.
- The HTTP accept filter still uses soupcall_set() to manage its internal
state machine, but other accept filters no longer have any explicit
knowlege of socket upcall internals aside from their return value.
- The various RPC client upcalls currently drop the socket buffer lock
while invoking soreceive() as a temporary band-aid. The plan for
the future is to add a new flag to allow soreceive() to be called with
the socket buffer locked.
- The AIO callback for socket I/O is now also invoked with the socket
buffer locked. Previously sowakeup() would drop the socket buffer
lock only to call aio_swake() which immediately re-acquired the socket
buffer lock for the duration of the function call.

Discussed with: rwatson, rmacklem

Update comment. soalloc() is no longer performing M_WAITOK memory allocations.

Submitted by: ru
MFC after: 3 days

Retire the MALLOC and FREE macros. They are an abomination unto style(9).

MFC after: 3 months

Implement ratelimiting for debug messages. For now, allow at most
one message per second. In the future might add a sysctl knob for
each socket family to fine tune this.

MFC after: 1 week

Allow RFCOMM servers to bind to a ''wildcard'' RFCOMM channel
zero (0). Actual RFCOMM channel will be assigned after listen(2)
call is done on a RFCOMM socket bound to a ''wildcard'' RFCOMM
channel zero (0).

Address locking issues in ng_btsocket_rfcomm_bind()

Submitted by: Heiko Wundram (Beenic) < wundram at beenic dot net >
MFC after: 1 week

Return EADDRNOTAVAIL instead of EDESTADDRREQ error when
listen(2) is called on improperly bound socket.

Suggested by: Iain Hibbert
Approved by: re (kensmith)
MFC after: 3 days

Replace sosend() with direct call to .pru_send method on the
L2CAP socket. This is to avoid LOR with sx(9) lock in sblock()
called from sosend_generic().

Approved by: re (kensmith)
MFC after: 1 week

- Catch up with ongoing rwatson's socket work;

- Fix a couple of LORs and panics;

- Temporarily remove the code that tries to cleanup sockets that stuck
on accepting queues (both complete and incomplete). I'm taking an ostrich
approach here until I find a better way to deal with sockets that were
disconnected before accepting (i.e. while socket was on complete or
incomplete accept queue).

Define mtu as u_int16_t not as int. This should fix problem with rfcomm
on sparc64.

Reported by: Andrew Belashov <bel at orel dot ru>
Tested by: Andrew Belashov <bel at orel dot ru>
MFC after: 3 days

soreceive_generic(), and sopoll_generic(). Add new functions sosend(),
soreceive(), and sopoll(), which are wrappers for pru_sosend,
pru_soreceive, and pru_sopoll, and are now used univerally by socket
consumers rather than either directly invoking the old so*() functions
or directly invoking the protocol switch method (about an even split
prior to this commit).

This completes an architectural change that was begun in 1996 to permit
protocols to provide substitute implementations, as now used by UDP.
Consumers now uniformly invoke sosend(), soreceive(), and sopoll() to
perform these operations on sockets -- in particular, distributed file
systems and socket system calls.

Architectural head nod: sam, gnn, wollman

Change semantics of socket close and detach. Add a new protocol switch
function, pru_close, to notify protocols that the file descriptor or
other consumer of a socket is closing the socket. pru_abort is now a
notification of close also, and no longer detaches. pru_detach is no
longer used to notify of close, and will be called during socket
tear-down by sofree() when all references to a socket evaporate after
an earlier call to abort or close the socket. This means detach is now
an unconditional teardown of a socket, whereas previously sockets could
persist after detach of the protocol retained a reference.

This faciliates sharing mutexes between layers of the network stack as
the mutex is required during the checking and removal of references at
the head of sofree(). With this change, pru_detach can now assume that
the mutex will no longer be required by the socket layer after
completion, whereas before this was not necessarily true.

Reviewed by: gnn

Chance protocol switch method pru_detach() so that it returns void
rather than an error. Detaches do not "fail", they other occur or
the protocol flags SS_PROTOREF to take ownership of the socket.

soclose() no longer looks at so_pcb to see if it's NULL, relying
entirely on the protocol to decide whether it's time to free the
socket or not using SS_PROTOREF. so_pcb is now entirely owned and
managed by the protocol code. Likewise, no longer test so_pcb in
other socket functions, such as soreceive(), which have no business
digging into protocol internals.

Protocol detach routines no longer try to free the socket on detach,
this is performed in the socket code if the protocol permits it.

In rts_detach(), no longer test for rp != NULL in detach, and
likewise in other protocols that don't permit a NULL so_pcb, reduce
the incidence of testing for it during detach.

netinet and netinet6 are not fully updated to this change, which
will be in an upcoming commit. In their current state they may leak
memory or panic.

MFC after: 3 months

Change protocol switch pru_abort() API so that it returns void rather
than an int, as an error here is not meaningful. Modify soabort() to
unconditionally free the socket on the return of pru_abort(), and
modify most protocols to no longer conditionally free the socket,
since the caller will do this.

This commit likely leaves parts of netinet and netinet6 in a situation
where they may panic or leak memory, as they have not are not fully
updated by this commit. This will be corrected shortly in followup
commits to these components.

MFC after: 3 months

Push the assignment of a new or updated so_qlimit from solisten()
following the protocol pru_listen() call to solisten_proto(), so
that it occurs under the socket lock acquisition that also sets
SO_ACCEPTCONN. This requires passing the new backlog parameter
to the protocol, which also allows the protocol to be aware of
changes in queue limit should it wish to do something about the
new queue limit. This continues a move towards the socket layer
acting as a library for the protocol.

Bump __FreeBSD_version due to a change in the in-kernel protocol
interface. This change has been tested with IPv4 and UNIX domain
sockets, but not other protocols.

In ng_btsocket_rfcomm_receive_frame() correctly set length variable when
EA bit is set in hdr->length (16-bit length). This currently has no effect
on the rest of the code. It just fixes the debug message.

MFC After: 3 weeks

move ptr use down to after null check

Noticed by: Coverity Prevent analysis tool
Reviewed by: emax

In the current world order, solisten() implements the state transition of
a socket from a regular socket to a listening socket able to accept new
connections. As part of this state transition, solisten() calls into the
protocol to update protocol-layer state. There were several bugs in this
implementation that could result in a race wherein a TCP SYN received
in the interval between the protocol state transition and the shortly
following socket layer transition would result in a panic in the TCP code,
as the socket would be in the TCPS_LISTEN state, but the socket would not
have the SO_ACCEPTCONN flag set.

This change does the following:

- Pushes the socket state transition from the socket layer solisten() to
to socket "library" routines called from the protocol. This permits
the socket routines to be called while holding the protocol mutexes,
preventing a race exposing the incomplete socket state transition to TCP
after the TCP state transition has completed. The check for a socket
layer state transition is performed by solisten_proto_check(), and the
actual transition is performed by solisten_proto().

- Holds the socket lock for the duration of the socket state test and set,
and over the protocol layer state transition, which is now possible as
the socket lock is acquired by the protocol layer, rather than vice
versa. This prevents additional state related races in the socket
layer.

This permits the dual transition of socket layer and protocol layer state
to occur while holding locks for both layers, making the two changes
atomic with respect to one another. Similar changes are likely require
elsewhere in the socket/protocol code.

Reported by: Peter Holm <peter@holm.cc>
Review and fixes from: emax, Antoine Brodin <antoine.brodin@laposte.net>
Philosophical head nod: gnn

/* -> /*- for license, minor formatting changes

Push acquisition of the accept mutex out of sofree() into the caller
(sorele()/sotryfree()):

- This permits the caller to acquire the accept mutex before the socket
mutex, avoiding sofree() having to drop the socket mutex and re-order,
which could lead to races permitting more than one thread to enter
sofree() after a socket is ready to be free'd.

- This also covers clearing of the so_pcb weak socket reference from
the protocol to the socket, preventing races in clearing and
evaluation of the reference such that sofree() might be called more
than once on the same socket.

This appears to close a race I was able to easily trigger by repeatedly
opening and resetting TCP connections to a host, in which the
tcp_close() code called as a result of the RST raced with the close()
of the accepted socket in the user process resulting in simultaneous
attempts to de-allocate the same socket. The new locking increases
the overhead for operations that may potentially free the socket, so we
will want to revise the synchronization strategy here as we normalize
the reference counting model for sockets. The use of the accept mutex
in freeing of sockets that are not listen sockets is primarily
motivated by the potential need to remove the socket from the
incomplete connection queue on its parent (listen) socket, so cleaning
up the reference model here may allow us to substantially weaken the
synchronization requirements.

RELENG_5_3 candidate.

MFC after: 3 days
Reviewed by: dwhite
Discussed with: gnn, dwhite, green
Reported by: Marc UBM Bocklet <ubm at u-boot-man dot de>
Reported by: Vlad <marchenko at gmail dot com>

Correct merge-o: make sure to unlock symmetrically socket buffer
locks on bluetooth sockets when clearing upcall flags.

Submitted by: emax

Merge additional socket buffer locking from rwatson_netperf:

- Lock down low hanging fruit use of sb_flags with socket buffer
lock.

- Lock down low hanging fruit use of so_state with socket lock.

- Lock down low hanging fruit use of so_options.

- Lock down low-hanging fruit use of sb_lowwat and sb_hiwat with
socket buffer lock.

- Annotate situations in which we unlock the socket lock and then
grab the receive socket buffer lock, which are currently actually
the same lock. Depending on how we want to play our cards, we
may want to coallesce these lock uses to reduce overhead.

- Convert a if()->panic() into a KASSERT relating to so_state in
soaccept().

- Remove a number of splnet()/splx() references.

More complex merging of socket and socket buffer locking to
follow.

The socket field so_state is used to hold a variety of socket related
flags relating to several aspects of socket functionality. This change
breaks out several bits relating to send and receive operation into a
new per-socket buffer field, sb_state, in order to facilitate locking.
This is required because, in order to provide more granular locking of
sockets, different state fields have different locking properties. The
following fields are moved to sb_state:

SS_CANTRCVMORE (so_state)
SS_CANTSENDMORE (so_state)
SS_RCVATMARK (so_state)

Rename respectively to:

SBS_CANTRCVMORE (so_rcv.sb_state)
SBS_CANTSENDMORE (so_snd.sb_state)
SBS_RCVATMARK (so_rcv.sb_state)

This facilitates locking by isolating fields to be located with other
identically locked fields, and permits greater granularity in socket
locking by avoiding storing fields with different locking semantics in
the same short (avoiding locking conflicts). In the future, we may
wish to coallesce sb_state and sb_flags; for the time being I leave
them separate and there is no additional memory overhead due to the
packing/alignment of shorts in the socket buffer structure.

Extend coverage of SOCK_LOCK(so) to include so_count, the socket
reference count:

- Assert SOCK_LOCK(so) macros that directly manipulate so_count:
soref(), sorele().

- Assert SOCK_LOCK(so) in macros/functions that rely on the state of
so_count: sofree(), sotryfree().

- Acquire SOCK_LOCK(so) before calling these functions or macros in
various contexts in the stack, both at the socket and protocol
layers.

- In some cases, perform soisdisconnected() before sotryfree(), as
this could result in frobbing of a non-present socket if
sotryfree() actually frees the socket.

- Note that sofree()/sotryfree() will release the socket lock even if
they don't free the socket.

Submitted by: sam
Sponsored by: FreeBSD Foundation
Obtained from: BSD/OS

Integrate accept locking from rwatson_netperf, introducing a new
global mutex, accept_mtx, which serializes access to the following
fields across all sockets:

so_qlen so_incqlen so_qstate
so_comp so_incomp so_list
so_head

While providing only coarse granularity, this approach avoids lock
order issues between sockets by avoiding ownership of the fields
by a specific socket and its per-socket mutexes.

While here, rewrite soclose(), sofree(), soaccept(), and
sonewconn() to add assertions, close additional races and address
lock order concerns. In particular:

- Reorganize the optimistic concurrency behavior in accept1() to
always allocate a file descriptor with falloc() so that if we do
find a socket, we don't have to encounter the "Oh, there wasn't
a socket" race that can occur if falloc() sleeps in the current
code, which broke inbound accept() ordering, not to mention
requiring backing out socket state changes in a way that raced
with the protocol level. We may want to add a lockless read of
the queue state if polling of empty queues proves to be important
to optimize.

- In accept1(), soref() the socket while holding the accept lock
so that the socket cannot be free'd in a race with the protocol
layer. Likewise in netgraph equivilents of the accept1() code.

- In sonewconn(), loop waiting for the queue to be small enough to
insert our new socket once we've committed to inserting it, or
races can occur that cause the incomplete socket queue to
overfill. In the previously implementation, it was sufficient
to simply tested once since calling soabort() didn't release
synchronization permitting another thread to insert a socket as
we discard a previous one.

- In soclose()/sofree()/et al, it is the responsibility of the
caller to remove a socket from the incomplete connection queue
before calling soabort(), which prevents soabort() from having
to walk into the accept socket to release the socket from its
queue, and avoids races when releasing the accept mutex to enter
soabort(), permitting soabort() to avoid lock ordering issues
with the caller.

- Generally cluster accept queue related operations together
throughout these functions in order to facilitate locking.

Annotate new locking in socketvar.h.

The SS_COMP and SS_INCOMP flags in the so_state field indicate whether
the socket is on an accept queue of a listen socket. This change
renames the flags to SQ_COMP and SQ_INCOMP, and moves them to a new
state field on the socket, so_qstate, as the locking for these flags
is substantially different for the locking on the remainder of the
flags in so_state.

Address few style issues pointed out by bde

Reviewed by: bde, ru

Make sure RFCOMM multiplexor channel does not hang in DISCONNECTING
state. Apparently it happens when both devices try to disconnect RFCOMM
multiplexor channel at the same time.

The scenario is as follows:

- local device initiates RFCOMM connection to the remote device. This
creates both RFCOMM multiplexor channel and data channel;

- remote device terminates RFCOMM data channel (inactivity timeout);

- local device acknowledges RFCOMM data channel termination. Because
there is no more active data channels and local device has initiated
connection it terminates RFCOMM multiplexor channel;

- remote device does not acknowledges RFCOMM multiplexor channel
termination. Instead it sends its own request to terminate RFCOMM
multiplexor channel. Even though local device acknowledges RFCOMM
multiplexor channel termination the remote device still keeps
L2CAP connection open.

Because of hanging RFCOMM multiplexor channel subsequent RFCOMM
connections between local and remote devices will fail.

Reported by: Johann Hugo <jhugo@icomtek.csir.co.za>

Rename dup_sockaddr() to sodupsockaddr() for consistency with other
functions in kern_socket.c.

Rename the "canwait" field to "mflags" and pass M_WAITOK and M_NOWAIT
in from the caller context rather than "1" or "0".

Correct mflags pass into mac_init_socket() from previous commit to not
include M_ZERO.

Submitted by: sam

Update Bluetooth code.

Reviewed by: M. Warner Losh <imp@bsdimp.com>; John Hay <jhay@freebsd.org>
Approved by: M. Warner Losh <imp@bsdimp.com> (mentor)

Use the <sys/bitstring.h> rather than <bitstring.h>

Part one of undating the bluetooth code to the newest version

Submitted by: Maksim Yevmenkin <m_evmenkin@yahoo.com>
Approved by: re@