The statistics and its proc output was not implemented as per-net in the
initial network namespace support by Mario Kicherer (8e8cda6d).
This patch adds the missing per-net statistics for the CAN subsystem.
Signed-off-by: NOliver Hartkopp <socketcan@hartkopp.net>
Signed-off-by: NMarc Kleine-Budde <mkl@pengutronix.de>

The namespace support for the CAN subsystem does not need any additional
memory. So when ".size = 0" there's no extra memory allocated by the system.
And therefore ".id" is obsolete too.
Signed-off-by: NOliver Hartkopp <socketcan@hartkopp.net>
Signed-off-by: NMarc Kleine-Budde <mkl@pengutronix.de>

The can_rx_alldev_list is a per-net data structure now and allocated in
can_pernet_init(). Make sure the memory is free'd in can_pernet_exit() too.
Signed-off-by: NOliver Hartkopp <socketcan@hartkopp.net>
Signed-off-by: NMarc Kleine-Budde <mkl@pengutronix.de>

This patch adds initial support for network namespaces. The changes only
enable support in the CAN raw, proc and af_can code. GW and BCM still
have their checks that ensure that they are used only from the main
namespace.

The patch boils down to moving the global structures, i.e. the global
filter list and their /proc stats, into a per-namespace structure and passing
around the corresponding "struct net" in a lot of different places.

Changes since v1:
 - rebased on current HEAD (2bfe01ef)
 - fixed overlong line
Signed-off-by: NMario Kicherer <dev@kicherer.org>
Signed-off-by: NMarc Kleine-Budde <mkl@pengutronix.de>

Zhang Yanmin reported crashes [1] and provided a patch adding a
synchronize_rcu() call in can_rx_unregister()

The main problem seems that the sockets themselves are not RCU
protected.

If CAN uses RCU for delivery, then sockets should be freed only after
one RCU grace period.

Recent kernels could use sock_set_flag(sk, SOCK_RCU_FREE), but let's
ease stable backports with the following fix instead.

[1]
BUG: unable to handle kernel NULL pointer dereference at (null)
IP: [<ffffffff81495e25>] selinux_socket_sock_rcv_skb+0x65/0x2a0

Call Trace:
 <IRQ>
 [<ffffffff81485d8c>] security_sock_rcv_skb+0x4c/0x60
 [<ffffffff81d55771>] sk_filter+0x41/0x210
 [<ffffffff81d12913>] sock_queue_rcv_skb+0x53/0x3a0
 [<ffffffff81f0a2b3>] raw_rcv+0x2a3/0x3c0
 [<ffffffff81f06eab>] can_rcv_filter+0x12b/0x370
 [<ffffffff81f07af9>] can_receive+0xd9/0x120
 [<ffffffff81f07beb>] can_rcv+0xab/0x100
 [<ffffffff81d362ac>] __netif_receive_skb_core+0xd8c/0x11f0
 [<ffffffff81d36734>] __netif_receive_skb+0x24/0xb0
 [<ffffffff81d37f67>] process_backlog+0x127/0x280
 [<ffffffff81d36f7b>] net_rx_action+0x33b/0x4f0
 [<ffffffff810c88d4>] __do_softirq+0x184/0x440
 [<ffffffff81f9e86c>] do_softirq_own_stack+0x1c/0x30
 <EOI>
 [<ffffffff810c76fb>] do_softirq.part.18+0x3b/0x40
 [<ffffffff810c8bed>] do_softirq+0x1d/0x20
 [<ffffffff81d30085>] netif_rx_ni+0xe5/0x110
 [<ffffffff8199cc87>] slcan_receive_buf+0x507/0x520
 [<ffffffff8167ef7c>] flush_to_ldisc+0x21c/0x230
 [<ffffffff810e3baf>] process_one_work+0x24f/0x670
 [<ffffffff810e44ed>] worker_thread+0x9d/0x6f0
 [<ffffffff810e4450>] ? rescuer_thread+0x480/0x480
 [<ffffffff810ebafc>] kthread+0x12c/0x150
 [<ffffffff81f9ccef>] ret_from_fork+0x3f/0x70
Reported-by: NZhang Yanmin <yanmin.zhang@intel.com>
Signed-off-by: NEric Dumazet <edumazet@google.com>
Acked-by: NOliver Hartkopp <socketcan@hartkopp.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The change to leave out procfs support in CAN when CONFIG_PROC_FS
is not set was incomplete and leads to a build error:

net/built-in.o: In function `can_init':
:(.init.text+0x9858): undefined reference to `can_stat_update'
ERROR: "can_stat_update" [net/can/can.ko] undefined!

This tries a better approach, encapsulating all of the calls
within IS_ENABLED(), so we also leave out the timer function
from the object file.
Signed-off-by: NArnd Bergmann <arnd@arndb.de>
Fixes: a20fadf8 ("can: build proc support only if CONFIG_PROC_FS is activated")
Signed-off-by: NMarc Kleine-Budde <mkl@pengutronix.de>

Commit 514ac99c "can: fix multiple delivery of a single CAN frame for
overlapping CAN filters" requires the skb->tstamp to be set to check for
identical CAN skbs.

Without timestamping to be required by user space applications this timestamp
was not generated which lead to commit 36c01245 "can: fix loss of CAN frames
in raw_rcv" - which forces the timestamp to be set in all CAN related skbuffs
by introducing several __net_timestamp() calls.

This forces e.g. out of tree drivers which are not using alloc_can{,fd}_skb()
to add __net_timestamp() after skbuff creation to prevent the frame loss fixed
in mainline Linux.

This patch removes the timestamp dependency and uses an atomic counter to
create an unique identifier together with the skbuff pointer.

Btw: the new skbcnt element introduced in struct can_skb_priv has to be
initialized with zero in out-of-tree drivers which are not using
alloc_can{,fd}_skb() too.
Signed-off-by: NOliver Hartkopp <socketcan@hartkopp.net>
Cc: linux-stable <stable@vger.kernel.org>
Signed-off-by: NMarc Kleine-Budde <mkl@pengutronix.de>

As reported by Manfred Schlaegl here

   http://marc.info/?l=linux-netdev&m=143482089824232&w=2

commit 514ac99c "can: fix multiple delivery of a single CAN frame for
overlapping CAN filters" requires the skb->tstamp to be set to check for
identical CAN skbs.

As net timestamping is influenced by several players (netstamp_needed and
netdev_tstamp_prequeue) Manfred missed a proper timestamp which leads to
CAN frame loss.

As skb timestamping became now mandatory for CAN related skbs this patch
makes sure that received CAN skbs always have a proper timestamp set.
Maybe there's a better solution in the future but this patch fixes the
CAN frame loss so far.
Reported-by: NManfred Schlaegl <manfred.schlaegl@gmx.at>
Signed-off-by: NOliver Hartkopp <socketcan@hartkopp.net>
Cc: linux-stable <stable@vger.kernel.org>
Signed-off-by: NMarc Kleine-Budde <mkl@pengutronix.de>

In preparation for changing how struct net is refcounted
on kernel sockets pass the knowledge that we are creating
a kernel socket from sock_create_kern through to sk_alloc.
Signed-off-by: N"Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

When accessing CAN network interfaces with AF_PACKET sockets e.g. by dhclient
this can lead to a skb_under_panic due to missing skb initialisations.

Add the missing initialisations at the CAN skbuff creation times on driver
level (rx path) and in the network layer (tx path).
Reported-by: NAustin Schuh <austin@peloton-tech.com>
Reported-by: NDaniel Steer <daniel.steer@mclaren.com>
Signed-off-by: NOliver Hartkopp <socketcan@hartkopp.net>
Cc: linux-stable <stable@vger.kernel.org>
Signed-off-by: NMarc Kleine-Budde <mkl@pengutronix.de>

Fix various spelling errors in the comments of the CAN modules.
Signed-off-by: NJeremiah Mahler <jmmahler@gmail.com>
Acked-by: NOliver Hartkopp <socketcan@hartkopp.net>
Signed-off-by: NMarc Kleine-Budde <mkl@pengutronix.de>

Several CAN modules use a design pattern with a banner[] variable at the
top which defines a string that is used once during init to print the
banner.  The string is also embedded with KERN_INFO which makes it
printk() specific.

Improve the code by eliminating the banner[] variable and moving the
string to where it is printed.  Then switch from printk(KERN_INFO to
pr_info() for the lines that were changed.
Signed-off-by: NJeremiah Mahler <jmmahler@gmail.com>
Acked-by: NOliver Hartkopp <socketcan@hartkopp.net>
Signed-off-by: NMarc Kleine-Budde <mkl@pengutronix.de>

In contrast to the direct access to the single SFF frame filters (which are
indexed by the SFF CAN ID itself) the single EFF frame filters are arranged
in a single linked hlist. To reduce the hlist traversal in the case of many
filter subscriptions a hash based access is introduced for single EFF filters.
Signed-off-by: NOliver Hartkopp <socketcan@hartkopp.net>
Signed-off-by: NMarc Kleine-Budde <mkl@pengutronix.de>

Self generated skbuffs in net/can/bcm.c are setting a skb->sk reference but
no explicit destructor which is enforced since Linux 3.11 with commit
376c7311 (net: add a temporary sanity check in skb_orphan()).

This patch adds some helper functions to make sure that a destructor is
properly defined when a sock reference is assigned to a CAN related skb.
To create an unshared skb owned by the original sock a common helper function
has been introduced to replace open coded functions to create CAN echo skbs.
Signed-off-by: NOliver Hartkopp <socketcan@hartkopp.net>
Tested-by: NAndre Naujoks <nautsch2@gmail.com>
Reviewed-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Correct common misspelling of "identify" as "indentify" throughout
the kernel
Signed-off-by: NMaxime Jayat <maxime@artisandeveloppeur.fr>
Signed-off-by: NJiri Kosina <jkosina@suse.cz>

So far, only net_device * could be passed along with netdevice notifier
event. This patch provides a possibility to pass custom structure
able to provide info that event listener needs to know.
Signed-off-by: NJiri Pirko <jiri@resnulli.us>

v2->v3: fix typo on simeth
	shortened dev_getter
	shortened notifier_info struct name
v1->v2: fix notifier_call parameter in call_netdevice_notifier()
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The rework of the kernel hlist implementation "hlist: drop the node parameter
from iterators" (b67bfe0d) created some
fallout in the form of non matching comments and obsolete code.

Additionally to the cleanup this patch adds a WARN() statement to catch the
caller of the wrong filter removal request.
Signed-off-by: NOliver Hartkopp <socketcan@hartkopp.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Replace printk(KERN_ERR with pr_err
Add space before {
Removed OOM messages
Signed-off-by: NValentin Ilie <valentin.ilie@gmail.com>
Acked-by: NOliver Hartkopp <socketcan@hartkopp.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

I'm not sure why, but the hlist for each entry iterators were conceived

        list_for_each_entry(pos, head, member)

The hlist ones were greedy and wanted an extra parameter:

        hlist_for_each_entry(tpos, pos, head, member)

Why did they need an extra pos parameter? I'm not quite sure. Not only
they don't really need it, it also prevents the iterator from looking
exactly like the list iterator, which is unfortunate.

Besides the semantic patch, there was some manual work required:

 - Fix up the actual hlist iterators in linux/list.h
 - Fix up the declaration of other iterators based on the hlist ones.
 - A very small amount of places were using the 'node' parameter, this
 was modified to use 'obj->member' instead.
 - Coccinelle didn't handle the hlist_for_each_entry_safe iterator
 properly, so those had to be fixed up manually.

The semantic patch which is mostly the work of Peter Senna Tschudin is here:

@@
iterator name hlist_for_each_entry, hlist_for_each_entry_continue, hlist_for_each_entry_from, hlist_for_each_entry_rcu, hlist_for_each_entry_rcu_bh, hlist_for_each_entry_continue_rcu_bh, for_each_busy_worker, ax25_uid_for_each, ax25_for_each, inet_bind_bucket_for_each, sctp_for_each_hentry, sk_for_each, sk_for_each_rcu, sk_for_each_from, sk_for_each_safe, sk_for_each_bound, hlist_for_each_entry_safe, hlist_for_each_entry_continue_rcu, nr_neigh_for_each, nr_neigh_for_each_safe, nr_node_for_each, nr_node_for_each_safe, for_each_gfn_indirect_valid_sp, for_each_gfn_sp, for_each_host;

type T;
expression a,c,d,e;
identifier b;
statement S;
@@

-T b;
    <+... when != b
(
hlist_for_each_entry(a,
- b,
c, d) S
|
hlist_for_each_entry_continue(a,
- b,
c) S
|
hlist_for_each_entry_from(a,
- b,
c) S
|
hlist_for_each_entry_rcu(a,
- b,
c, d) S
|
hlist_for_each_entry_rcu_bh(a,
- b,
c, d) S
|
hlist_for_each_entry_continue_rcu_bh(a,
- b,
c) S
|
for_each_busy_worker(a, c,
- b,
d) S
|
ax25_uid_for_each(a,
- b,
c) S
|
ax25_for_each(a,
- b,
c) S
|
inet_bind_bucket_for_each(a,
- b,
c) S
|
sctp_for_each_hentry(a,
- b,
c) S
|
sk_for_each(a,
- b,
c) S
|
sk_for_each_rcu(a,
- b,
c) S
|
sk_for_each_from
-(a, b)
+(a)
S
+ sk_for_each_from(a) S
|
sk_for_each_safe(a,
- b,
c, d) S
|
sk_for_each_bound(a,
- b,
c) S
|
hlist_for_each_entry_safe(a,
- b,
c, d, e) S
|
hlist_for_each_entry_continue_rcu(a,
- b,
c) S
|
nr_neigh_for_each(a,
- b,
c) S
|
nr_neigh_for_each_safe(a,
- b,
c, d) S
|
nr_node_for_each(a,
- b,
c) S
|
nr_node_for_each_safe(a,
- b,
c, d) S
|
- for_each_gfn_sp(a, c, d, b) S
+ for_each_gfn_sp(a, c, d) S
|
- for_each_gfn_indirect_valid_sp(a, c, d, b) S
+ for_each_gfn_indirect_valid_sp(a, c, d) S
|
for_each_host(a,
- b,
c) S
|
for_each_host_safe(a,
- b,
c, d) S
|
for_each_mesh_entry(a,
- b,
c, d) S
)
    ...+>

[akpm@linux-foundation.org: drop bogus change from net/ipv4/raw.c]
[akpm@linux-foundation.org: drop bogus hunk from net/ipv6/raw.c]
[akpm@linux-foundation.org: checkpatch fixes]
[akpm@linux-foundation.org: fix warnings]
[akpm@linux-foudnation.org: redo intrusive kvm changes]
Tested-by: NPeter Senna Tschudin <peter.senna@gmail.com>
Acked-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: NSasha Levin <sasha.levin@oracle.com>
Cc: Wu Fengguang <fengguang.wu@intel.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Gleb Natapov <gleb@redhat.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Signed-off-by: NAndi Kleen <ak@linux.intel.com>
Cc: Oliver Hartkopp <socketcan@hartkopp.net>
Cc: David Miller <davem@davemloft.net>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

- handle ETH_P_CAN and ETH_P_CANFD skbuffs
- update sanity checks for CAN and CAN FD
- make sure the CAN frame can pass the selected CAN netdevice on send
- bump core version and abi version to indicate the new CAN FD support
Signed-off-by: NOliver Hartkopp <socketcan@hartkopp.net>
Signed-off-by: NMarc Kleine-Budde <mkl@pengutronix.de>

- add new struct canfd_frame
- check identical element offsets in struct can_frame and struct canfd_frame
- new ETH_P_CANFD definition to tag CAN FD skbs correctly
- add CAN_MTU and CANFD_MTU definitions for easy frame and mode detection
- add CAN[FD]_MAX_[DLC|DLEN] helper constants to remove hard coded values
- update existing struct can_frame with helper constants and comments
Signed-off-by: NOliver Hartkopp <socketcan@hartkopp.net>
Signed-off-by: NMarc Kleine-Budde <mkl@pengutronix.de>

As Heinz-Juergen Oertel pointed out 'CAN error frames' are a already defined
term for the CAN protocol violation indication on the wire.

To avoid confusion with the error messages created by CAN drivers available
via CAN RAW sockets update the documentation and change the naming from
'error frames' to 'error messages' or 'error message frames'.
Signed-off-by: NOliver Hartkopp <socketcan@hartkopp.net>
Signed-off-by: NMarc Kleine-Budde <mkl@pengutronix.de>

The BerliOS project, which currently hosts our mailinglist, will
close with the end of the year. Now take the chance and remove all
occurrences of the mailinglist address from the source files.
Signed-off-by: NMarc Kleine-Budde <mkl@pengutronix.de>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This is important for SMP platform to check if timer function is
executing on other CPU with deleting the timer.

Signed-off-by: Rajan Aggarwal <Rajan Aggarwal rajan.aggarwal85@gmail.com>
Acked-by: NOliver Hartkopp <socketcan@hartkopp.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

When assigning a NULL value to an RCU protected pointer, no barrier
is needed. The rcu_assign_pointer, used to handle that but will soon
change to not handle the special case.

Convert all rcu_assign_pointer of NULL value.

//smpl
@@ expression P; @@

- rcu_assign_pointer(P, NULL)
+ RCU_INIT_POINTER(P, NULL)

// </smpl>
Signed-off-by: NStephen Hemminger <shemminger@vyatta.com>
Acked-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Since printk_ratelimit() shouldn't be used anymore (see comment in
include/linux/printk.h), replace it with printk_ratelimited().
Signed-off-by: NManuel Zerpies <manuel.f.zerpies@ww.stud.uni-erlangen.de>
Signed-off-by: NDavid S. Miller <davem@conan.davemloft.net>

can: rename can_try_module_get to can_get_proto

can_try_module_get does return a struct can_proto.
The name explains what is done in so much detail that a caller
may not notice that a struct can_proto is locked/unlocked.
Signed-off-by: NKurt Van Dijck <kurt.van.dijck@eia.be>
Acked-by: NOliver Hartkopp <socketcan@hartkopp.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

commit 53914b67 had the
same message. That commit did put everything in place but
did not make can_proto const itself.
Signed-off-by: NKurt Van Dijck <kurt.van.dijck@eia.be>
Acked-by: NOliver Hartkopp <socketcan@hartkopp.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch removes spin_locks at CAN socket creation time by using RCU.

Inspired by the discussion with Kurt van Dijck and Eric Dumazet the RCU code
was partly derived from af_phonet.c
Signed-off-by: NOliver Hartkopp <socketcan@hartkopp.net>
Reviewed-by: NEric Dumazet <eric.dumazet@gmail.com>
Acked-by: NKurt Van Dijck <kurt.van.dijck@eia.be>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

can_ioctl is the only reason for struct proto to be non-const.
script/check-patch.pl suggests struct proto be const.

Setting the reference to the common can_ioctl() in all CAN protocols directly
removes the need to make the struct proto writable in af_can.c
Signed-off-by: NKurt Van Dijck <kurt.van.dijck@eia.be>
Signed-off-by: NOliver Hartkopp <socketcan@hartkopp.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

In commit 20dd3850 "can: Speed up CAN frame
receiption by using ml_priv" the formerly used hlist of receiver lists for
each CAN netdevice has been replaced. 

The hlist content ensured only CAN netdevices to be accessed by the
can_rx_(un)register() functions which accidently dropped away together with
the hlist receiver implementation.

This patch re-introduces the check for CAN netdevices in can_rx_(un)register().
Signed-off-by: NOliver Hartkopp <oliver@hartkopp.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

this patch removes the hlist that contains the CAN receiver filter lists.
It uses the 'midlayer private' pointer ml_priv and links the filters directly
to the CAN netdevice, which allows to omit the walk through the complete CAN
devices hlist for each received CAN frame.

This patch is tested and does not remove any locking.
Signed-off-by: NOliver Hartkopp <oliver@hartkopp.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Not including net/atm/

Compiled tested x86 allyesconfig only
Added a > 80 column line or two, which I ignored.
Existing checkpatch plaints willfully, cheerfully ignored.
Signed-off-by: NJoe Perches <joe@perches.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Generated with the following semantic patch

@@
struct net *n1;
struct net *n2;
@@
- n1 == n2
+ net_eq(n1, n2)

@@
struct net *n1;
struct net *n2;
@@
- n1 != n2
+ !net_eq(n1, n2)

applied over {include,net,drivers/net}.
Signed-off-by: NOctavian Purdila <opurdila@ixiacom.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The generic __sock_create function has a kern argument which allows the
security system to make decisions based on if a socket is being created by
the kernel or by userspace.  This patch passes that flag to the
net_proto_family specific create function, so it can do the same thing.
Signed-off-by: NEric Paris <eparis@redhat.com>
Acked-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

struct can_proto had a capability field which wasn't ever used.  It is
dropped entirely.

struct inet_protosw had a capability field which can be more clearly
expressed in the code by just checking if sock->type = SOCK_RAW.
Signed-off-by: NEric Paris <eparis@redhat.com>
Acked-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

All usages of structure net_proto_ops should be declared const.
Signed-off-by: NStephen Hemminger <shemminger@vyatta.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

When using nanosleep() in an userspace application we get a ratelimit warning

NOHZ: local_softirq_pending 08

for 10 times.

The echo of CAN frames is done from process context and softirq context only.
Therefore the usage of netif_rx() was wrong (for years).

This patch replaces netif_rx() with netif_rx_ni() which has to be used from
process/softirq context. It also adds a missing comment that can_send() must
no be used from hardirq context.
Signed-off-by: NOliver Hartkopp <oliver@hartkopp.net>
Signed-off-by: NUrs Thuermann <urs@isnogud.escape.de>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Dropped skb's should be documented by an appropriate return value.
Use the correct NET_RX_DROP and NET_RX_SUCCESS values for that reason.
Signed-off-by: NOliver Hartkopp <oliver@hartkopp.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>