Make use of key preparsing in the RxRPC protocol so that quota size
determination can take place prior to keyring locking when a key is being
added.
Signed-off-by: NDavid Howells <dhowells@redhat.com>
Acked-by: NSteve Dickson <steved@redhat.com>

There may be padding on the ticket contained in the key payload, so just ensure
that the claimed token length is large enough, rather than exactly the right
size.
Signed-off-by: NNathaniel Wesley Filardo <nwf@cs.jhu.edu>
Signed-off-by: NDavid Howells <dhowells@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Several spots in the kernel perform a sequence like:

	skb_queue_tail(&sk->s_receive_queue, skb);
	sk->sk_data_ready(sk, skb->len);

But at the moment we place the SKB onto the socket receive queue it
can be consumed and freed up.  So this skb->len access is potentially
to freed up memory.

Furthermore, the skb->len can be modified by the consumer so it is
possible that the value isn't accurate.

And finally, no actual implementation of this callback actually uses
the length argument.  And since nobody actually cared about it's
value, lots of call sites pass arbitrary values in such as '0' and
even '1'.

So just remove the length argument from the callback, that way there
is no confusion whatsoever and all of these use-after-free cases get
fixed as a side effect.

Based upon a patch by Eric Dumazet and his suggestion to audit this
issue tree-wide.
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Keep track of rxrpc_call structures in a hashtable so they can be
found directly from the network parameters which define the call.

This allows incoming packets to be routed directly to a call without walking
through hierarchy of peer -> transport -> connection -> call and all the
spinlocks that that entailed.
Signed-off-by: NTim Smith <tim@electronghost.co.uk>
Signed-off-by: NDavid Howells <dhowells@redhat.com>

Set the RxRPC header flag to request an ACK packet for every odd-numbered DATA
packet unless it's the last one (which implicitly requests an ACK anyway).
This is similar to how librx appears to work.

If we don't do this, we'll send out a full window of packets and then just sit
there until the other side gets bored and sends an ACK to indicate that it's
been idle for a while and has received no new packets.

Requesting a lot of ACKs shouldn't be a problem as ACKs should be merged when
possible.

As AF_RXRPC currently works, it will schedule an ACK to be generated upon
receipt of a DATA packet with the ACK-request packet set - and in the time
taken to schedule this in a work queue, several other packets are likely to
arrive and then all get ACK'd together.
Signed-off-by: NDavid Howells <dhowells@redhat.com>

Expose RxRPC parameters via sysctls to control the Rx window size, the Rx MTU
maximum size and the number of packets that can be glued into a jumbo packet.

More info added to Documentation/networking/rxrpc.txt.
Signed-off-by: NDavid Howells <dhowells@redhat.com>

Improve ACK production by the following means:

 (1) Don't send an ACK_REQUESTED ack immediately even if the RXRPC_MORE_PACKETS
     flag isn't set on a data packet that has also has RXRPC_REQUEST_ACK set.

     MORE_PACKETS just means that the sender just emptied its Tx data buffer.
     More data will be forthcoming unless RXRPC_LAST_PACKET is also flagged.

     It is possible to see runs of DATA packets with MORE_PACKETS unset that
     aren't waiting for an ACK.

     It is therefore better to wait a small instant to see if we can combine an
     ACK for several packets.

 (2) Don't send an ACK_IDLE ack immediately unless we're responding to the
     terminal data packet of a call.

     Whilst sending an ACK_IDLE mid-call serves to let the other side know
     that we won't be asking it to resend certain Tx buffers and that it can
     discard them, spamming it with loads of acks just because we've
     temporarily run out of data just distracts it.

 (3) Put the ACK_IDLE ack generation timeout up to half a second rather than a
     single jiffy.  Just because we haven't been given more data immediately
     doesn't mean that more isn't forthcoming.  The other side may be busily
     finding the data to send to us.
Signed-off-by: NDavid Howells <dhowells@redhat.com>

Add sysctls for configuring RxRPC protocol handling, specifically controls on
delays before ack generation, the delay before resending a packet, the maximum
lifetime of a call and the expiration times of calls, connections and
transports that haven't been recently used.

More info added in Documentation/networking/rxrpc.txt.
Signed-off-by: NDavid Howells <dhowells@redhat.com>

AF_RXRPC sends UDP packets with the "Don't Fragment" bit set in an attempt to
determine the maximum packet size between the local socket and the peer by
invoking the generation of ICMP_FRAG_NEEDED packets.

Once a packet is sent with the "Don't Fragment" bit set, it is then
inconvenient to break it up as that requires recalculating all the rxrpc serial
and sequence numbers and reencrypting all the fragments, so we switch off the
"Don't Fragment" service temporarily and send the bounced packet again.  Future
packets then use the new MTU.

That's all fine.  The problem lies in rxrpc_UDP_error_report() where the code
that deals with ICMP_FRAG_NEEDED packets lives.  Packets of this type have a
field (ee_info) to indicate the maximum packet size at the reporting node - but
sometimes ee_info isn't filled in and is just left as 0 and the code must allow
for this.

When ee_info is 0, the code should take the MTU size we're currently using and
reduce it for the next packet we want to send.  However, it takes ee_info
(which is known to be 0) and tries to reduce that instead.

This was discovered by Coverity.
Reported-by: NDave Jones <davej@redhat.com>
Signed-off-by: NDavid Howells <dhowells@redhat.com>

When an ABORT is sent, aborting a connection, the sender quite reasonably
forgets about the connection.  If another frame is received, another ABORT
will be sent.  When the receiver gets it, it no longer applies to an extant
connection, so an ABORT is sent, and so on...

Prevent this by never sending a rejection for an ABORT packet.
Signed-off-by: NTim Smith <tim@electronghost.co.uk>
Signed-off-by: NDavid Howells <dhowells@redhat.com>

The UDP checksum was already verified in rxrpc_data_ready() - which calls
skb_checksum_complete() - as the RxRPC packet header contains no checksum of
its own.  Subsequent calls to skb_copy_and_csum_datagram_iovec() are thus
redundant and are, in any case, being passed only a subset of the UDP payload -
so the checksum will always fail if that path is taken.

So there is no need to check skb->ip_summed in rxrpc_recvmsg(), and no need for
the csum_copy_error: exit path.
Signed-off-by: NTim Smith <tim@electronghost.co.uk>
Signed-off-by: NDavid Howells <dhowells@redhat.com>

On input, CHECKSUM_PARTIAL should be treated the same way as
CHECKSUM_UNNECESSARY. See include/linux/skbuff.h
Signed-off-by: NTim Smith <tim@electronghost.co.uk>
Signed-off-by: NDavid Howells <dhowells@redhat.com>

skb_kill_datagram() does not dequeue the skb when MSG_PEEK is unset.
This leaves a free'd skb on the queue, resulting a double-free later.

Without this, the following oops can occur:

BUG: unable to handle kernel NULL pointer dereference at 0000000000000008
IP: [<ffffffff8154fcf7>] skb_dequeue+0x47/0x70
PGD 0
Oops: 0002 [#1] SMP
Modules linked in: af_rxrpc ...
CPU: 0 PID: 1191 Comm: listen Not tainted 3.12.0+ #4
Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
task: ffff8801183536b0 ti: ffff880035c92000 task.ti: ffff880035c92000
RIP: 0010:[<ffffffff8154fcf7>] skb_dequeue+0x47/0x70
RSP: 0018:ffff880035c93db8  EFLAGS: 00010097
RAX: 0000000000000246 RBX: ffff8800d2754b00 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000202 RDI: ffff8800d254c084
RBP: ffff880035c93dd0 R08: ffff880035c93cf0 R09: ffff8800d968f270
R10: 0000000000000000 R11: 0000000000000293 R12: ffff8800d254c070
R13: ffff8800d254c084 R14: ffff8800cd861240 R15: ffff880119b39720
FS:  00007f37a969d740(0000) GS:ffff88011fc00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
CR2: 0000000000000008 CR3: 00000000d4413000 CR4: 00000000000006f0
Stack:
 ffff8800d254c000 ffff8800d254c070 ffff8800d254c2c0 ffff880035c93df8
 ffffffffa041a5b8 ffff8800cd844c80 ffffffffa04385a0 ffff8800cd844cb0
 ffff880035c93e18 ffffffff81546cef ffff8800d45fea00 0000000000000008
Call Trace:
 [<ffffffffa041a5b8>] rxrpc_release+0x128/0x2e0 [af_rxrpc]
 [<ffffffff81546cef>] sock_release+0x1f/0x80
 [<ffffffff81546d62>] sock_close+0x12/0x20
 [<ffffffff811aaba1>] __fput+0xe1/0x230
 [<ffffffff811aad3e>] ____fput+0xe/0x10
 [<ffffffff810862cc>] task_work_run+0xbc/0xe0
 [<ffffffff8106a3be>] do_exit+0x2be/0xa10
 [<ffffffff8116dc47>] ? do_munmap+0x297/0x3b0
 [<ffffffff8106ab8f>] do_group_exit+0x3f/0xa0
 [<ffffffff8106ac04>] SyS_exit_group+0x14/0x20
 [<ffffffff8166b069>] system_call_fastpath+0x16/0x1b
Signed-off-by: NTim Smith <tim@electronghost.co.uk>
Signed-off-by: NDavid Howells <dhowells@redhat.com>

If rx->conn is not NULL, rxrpc_connect_exclusive() does not
acquire the transport's client lock, but it still releases it.

The patch adds locking of the spinlock to this path.

Found by Linux Driver Verification project (linuxtesting.org).
Signed-off-by: NAlexey Khoroshilov <khoroshilov@ispras.ru>
Signed-off-by: NDavid Howells <dhowells@redhat.com>

Smatch complains because we are using an untrusted index into the
rxrpc_acks[] array.  It's just a read and it's only in the debug code,
but it's simple enough to add a check and fix it.
Signed-off-by: NDan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This is a follow-up patch to f3d33426 ("net: rework recvmsg
handler msg_name and msg_namelen logic").

DECLARE_SOCKADDR validates that the structure we use for writing the
name information to is not larger than the buffer which is reserved
for msg->msg_name (which is 128 bytes). Also use DECLARE_SOCKADDR
consistently in sendmsg code paths.
Signed-off-by: NSteffen Hurrle <steffen@hurrle.net>
Suggested-by: NHannes Frederic Sowa <hannes@stressinduktion.org>
Acked-by: NHannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch now always passes msg->msg_namelen as 0. recvmsg handlers must
set msg_namelen to the proper size <= sizeof(struct sockaddr_storage)
to return msg_name to the user.

This prevents numerous uninitialized memory leaks we had in the
recvmsg handlers and makes it harder for new code to accidentally leak
uninitialized memory.

Optimize for the case recvfrom is called with NULL as address. We don't
need to copy the address at all, so set it to NULL before invoking the
recvmsg handler. We can do so, because all the recvmsg handlers must
cope with the case a plain read() is called on them. read() also sets
msg_name to NULL.

Also document these changes in include/linux/net.h as suggested by David
Miller.

Changes since RFC:

Set msg->msg_name = NULL if user specified a NULL in msg_name but had a
non-null msg_namelen in verify_iovec/verify_compat_iovec. This doesn't
affect sendto as it would bail out earlier while trying to copy-in the
address. It also more naturally reflects the logic by the callers of
verify_iovec.

With this change in place I could remove "
if (!uaddr || msg_sys->msg_namelen == 0)
	msg->msg_name = NULL
".

This change does not alter the user visible error logic as we ignore
msg_namelen as long as msg_name is NULL.

Also remove two unnecessary curly brackets in ___sys_recvmsg and change
comments to netdev style.

Cc: David Miller <davem@davemloft.net>
Suggested-by: NEric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: NHannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

There are a mix of function prototypes with and without extern
in the kernel sources.  Standardize on not using extern for
function prototypes.

Function prototypes don't need to be written with extern.
extern is assumed by the compiler.  Its use is as unnecessary as
using auto to declare automatic/local variables in a block.
Signed-off-by: NJoe Perches <joe@perches.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

proc_net_remove is only used to remove proc entries
that under /proc/net,it's not a general function for
removing proc entries of netns. if we want to remove
some proc entries which under /proc/net/stat/, we still
need to call remove_proc_entry.

this patch use remove_proc_entry to replace proc_net_remove.
we can remove proc_net_remove after this patch.
Signed-off-by: NGao feng <gaofeng@cn.fujitsu.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Right now, some modules such as bonding use proc_create
to create proc entries under /proc/net/, and other modules
such as ipv4 use proc_net_fops_create.

It looks a little chaos.this patch changes all of
proc_net_fops_create to proc_create. we can remove
proc_net_fops_create after this patch.
Signed-off-by: NGao feng <gaofeng@cn.fujitsu.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The CONFIG_EXPERIMENTAL config item has not carried much meaning for a
while now and is almost always enabled by default. As agreed during the
Linux kernel summit, remove it from any "depends on" lines in Kconfigs.

CC: "David S. Miller" <davem@davemloft.net>
Signed-off-by: NKees Cook <keescook@chromium.org>
Acked-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NYOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Give the key type the opportunity to preparse the payload prior to the
instantiation and update routines being called.  This is done with the
provision of two new key type operations:

	int (*preparse)(struct key_preparsed_payload *prep);
	void (*free_preparse)(struct key_preparsed_payload *prep);

If the first operation is present, then it is called before key creation (in
the add/update case) or before the key semaphore is taken (in the update and
instantiate cases).  The second operation is called to clean up if the first
was called.

preparse() is given the opportunity to fill in the following structure:

	struct key_preparsed_payload {
		char		*description;
		void		*type_data[2];
		void		*payload;
		const void	*data;
		size_t		datalen;
		size_t		quotalen;
	};

Before the preparser is called, the first three fields will have been cleared,
the payload pointer and size will be stored in data and datalen and the default
quota size from the key_type struct will be stored into quotalen.

The preparser may parse the payload in any way it likes and may store data in
the type_data[] and payload fields for use by the instantiate() and update()
ops.

The preparser may also propose a description for the key by attaching it as a
string to the description field.  This can be used by passing a NULL or ""
description to the add_key() system call or the key_create_or_update()
function.  This cannot work with request_key() as that required the description
to tell the upcall about the key to be created.

This, for example permits keys that store PGP public keys to generate their own
name from the user ID and public key fingerprint in the key.

The instantiate() and update() operations are then modified to look like this:

	int (*instantiate)(struct key *key, struct key_preparsed_payload *prep);
	int (*update)(struct key *key, struct key_preparsed_payload *prep);

and the new payload data is passed in *prep, whether or not it was preparsed.
Signed-off-by: NDavid Howells <dhowells@redhat.com>
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>

In net/dns_resolver/dns_key.c and net/rxrpc/ar-key.c make them
work with user namespaces enabled where key_alloc takes kuids and kgids.
Pass GLOBAL_ROOT_UID and GLOBAL_ROOT_GID instead of bare 0's.

Cc: Sage Weil <sage@inktank.com>
Cc: ceph-devel@vger.kernel.org
Cc: David Howells <dhowells@redhat.com>
Cc: David Miller <davem@davemloft.net>
Cc: linux-afs@lists.infradead.org
Acked-by: NSerge Hallyn <serge.hallyn@canonical.com>
Signed-off-by: NEric W. Biederman <ebiederm@xmission.com>

Give the key type the opportunity to preparse the payload prior to the
instantiation and update routines being called.  This is done with the
provision of two new key type operations:

	int (*preparse)(struct key_preparsed_payload *prep);
	void (*free_preparse)(struct key_preparsed_payload *prep);

If the first operation is present, then it is called before key creation (in
the add/update case) or before the key semaphore is taken (in the update and
instantiate cases).  The second operation is called to clean up if the first
was called.

preparse() is given the opportunity to fill in the following structure:

	struct key_preparsed_payload {
		char		*description;
		void		*type_data[2];
		void		*payload;
		const void	*data;
		size_t		datalen;
		size_t		quotalen;
	};

Before the preparser is called, the first three fields will have been cleared,
the payload pointer and size will be stored in data and datalen and the default
quota size from the key_type struct will be stored into quotalen.

The preparser may parse the payload in any way it likes and may store data in
the type_data[] and payload fields for use by the instantiate() and update()
ops.

The preparser may also propose a description for the key by attaching it as a
string to the description field.  This can be used by passing a NULL or ""
description to the add_key() system call or the key_create_or_update()
function.  This cannot work with request_key() as that required the description
to tell the upcall about the key to be created.

This, for example permits keys that store PGP public keys to generate their own
name from the user ID and public key fingerprint in the key.

The instantiate() and update() operations are then modified to look like this:

	int (*instantiate)(struct key *key, struct key_preparsed_payload *prep);
	int (*update)(struct key *key, struct key_preparsed_payload *prep);

and the new payload data is passed in *prep, whether or not it was preparsed.
Signed-off-by: NDavid Howells <dhowells@redhat.com>

Fix incorrect start markers, wrapped summary lines, missing section
breaks, incorrect separators, and some name mismatches.
Signed-off-by: NBen Hutchings <bhutchings@solarflare.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

If list_for_each_entry, etc complete a traversal of the list, the iterator
variable ends up pointing to an address at an offset from the list head,
and not a meaningful structure.  Thus this value should not be used after
the end of the iterator.  This seems to be a copy-paste bug from a previous
debugging message, and so the meaningless value is just deleted.

This problem was found using Coccinelle (http://coccinelle.lip6.fr/).
Signed-off-by: NJulia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

There is zero point to this function.

It's only real substance is to perform an extremely outdated BSD4.2
ICMP check, which we can safely remove.  If you really have a MTU
limited link being routed by a BSD4.2 derived system, here's a nickel
go buy yourself a real router.

The other actions of ip_rt_frag_needed(), checking and conditionally
updating the peer, are done by the per-protocol handlers of the ICMP
event.

TCP, UDP, et al. have a handler which will receive this event and
transmit it back into the associated route via dst_ops->update_pmtu().

This simplification is important, because it eliminates the one place
where we do not have a proper route context in which to make an
inetpeer lookup.
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Use of "unsigned int" is preferred to bare "unsigned" in net tree.
Signed-off-by: NEric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The first parameter should be "number of elements" and the second parameter
should be "element size".
Signed-off-by: NAxel Lin <axel.lin@gmail.com>
Acked-by: NDavid Howells <dhowells@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

DaveM said:
   Please, this kind of stuff rots forever and not using bool properly
   drives me crazy.

Joe Perches <joe@perches.com> gave me the spatch script:

	@@
	bool b;
	@@
	-b = 0
	+b = false
	@@
	bool b;
	@@
	-b = 1
	+b = true

I merely installed coccinelle, read the documentation and took credit.
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The semantic patch that makes this change is available
in scripts/coccinelle/api/memdup.cocci.
Signed-off-by: NThomas Meyer <thomas@m3y3r.de>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

These files are non modular, but need to export symbols using
the macros now living in export.h -- call out the include so
that things won't break when we remove the implicit presence
of module.h from everywhere.
Signed-off-by: NPaul Gortmaker <paul.gortmaker@windriver.com>

This is identical to the case I fixed in rxrpc_get_peer()
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

I backed off from trying to just eliminate this variable, since
transforming atomic_inc_return() into atomic_inc() takes away
the memory barriers.
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The idea here is this minimizes the number of places one has to edit
in order to make changes to how flows are defined and used.
Signed-off-by: NDavid S. Miller <davem@davemloft.net>