Use new function to avoid doing read_lock().
Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Acked-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Oliver Hartkopp <oliver@hartkopp.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
bcm_proc_getifname() is called with RTNL and dev_base_lock
not held. It calls __dev_get_by_index() without locks, and
this is illegal (might crash)
Close the race by holding dev_base_lock and copying dev->name
in the protected section.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Oliver Hartkopp <oliver@hartkopp.net>
Signed-off-by: David 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: Eric Paris <eparis@redhat.com>
Acked-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Create a new socket level option to report number of queue overflows
Recently I augmented the AF_PACKET protocol to report the number of frames lost
on the socket receive queue between any two enqueued frames. This value was
exported via a SOL_PACKET level cmsg. AFter I completed that work it was
requested that this feature be generalized so that any datagram oriented socket
could make use of this option. As such I've created this patch, It creates a
new SOL_SOCKET level option called SO_RXQ_OVFL, which when enabled exports a
SOL_SOCKET level cmsg that reports the nubmer of times the sk_receive_queue
overflowed between any two given frames. It also augments the AF_PACKET
protocol to take advantage of this new feature (as it previously did not touch
sk->sk_drops, which this patch uses to record the overflow count). Tested
successfully by me.
Notes:
1) Unlike my previous patch, this patch simply records the sk_drops value, which
is not a number of drops between packets, but rather a total number of drops.
Deltas must be computed in user space.
2) While this patch currently works with datagram oriented protocols, it will
also be accepted by non-datagram oriented protocols. I'm not sure if thats
agreeable to everyone, but my argument in favor of doing so is that, for those
protocols which aren't applicable to this option, sk_drops will always be zero,
and reporting no drops on a receive queue that isn't used for those
non-participating protocols seems reasonable to me. This also saves us having
to code in a per-protocol opt in mechanism.
3) This applies cleanly to net-next assuming that commit
977750076d (my af packet cmsg patch) is reverted
Signed-off-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
create_proc_read_entry() is going to be removed soon.
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add appropriate MODULE_ALIAS() to facilitate autoloading of can protocol drivers
Signed-off-by: Lothar Wassmann <LW@KARO-electronics.de>
Acked-by: Oliver Hartkopp <oliver@hartkopp.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Fix a use after free bug in can protocol drivers
The release functions of the can protocol drivers lack a call to
sock_orphan() which leads to referencing freed memory under certain
circumstances.
This patch fixes a bug reported here:
https://lists.berlios.de/pipermail/socketcan-users/2009-July/000985.html
Signed-off-by: Lothar Wassmann <LW@KARO-electronics.de>
Acked-by: Oliver Hartkopp <oliver@hartkopp.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Setting ->owner as done currently (pde->owner = THIS_MODULE) is racy
as correctly noted at bug #12454. Someone can lookup entry with NULL
->owner, thus not pinning enything, and release it later resulting
in module refcount underflow.
We can keep ->owner and supply it at registration time like ->proc_fops
and ->data.
But this leaves ->owner as easy-manipulative field (just one C assignment)
and somebody will forget to unpin previous/pin current module when
switching ->owner. ->proc_fops is declared as "const" which should give
some thoughts.
->read_proc/->write_proc were just fixed to not require ->owner for
protection.
rmmod'ed directories will be empty and return "." and ".." -- no harm.
And directories with tricky enough readdir and lookup shouldn't be modular.
We definitely don't want such modular code.
Removing ->owner will also make PDE smaller.
So, let's nuke it.
Kudos to Jeff Layton for reminding about this, let's say, oversight.
http://bugzilla.kernel.org/show_bug.cgi?id=12454
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Due to the loopback functionality in can_send() we can not invoke it
from hardirq context which was done inside the
bcm_tx_timeout_handler() hrtimer callback:
[ 700.361154] [<c012228c>] warn_slowpath+0x80/0xb6
[ 700.361163] [<c013d559>] valid_state+0x125/0x136
[ 700.361171] [<c013d858>] mark_lock+0x18e/0x332
[ 700.361180] [<c013e300>] __lock_acquire+0x12e/0xb1e
[ 700.361189] [<f8ab5915>] bcm_tx_timeout_handler+0x0/0xbc [can_bcm]
[ 700.361198] [<c031e20a>] dev_queue_xmit+0x191/0x479
[ 700.361206] [<c01262a7>] __local_bh_disable+0x2b/0x64
[ 700.361213] [<c031e20a>] dev_queue_xmit+0x191/0x479
[ 700.361225] [<f8aa69a1>] can_send+0xd7/0x11a [can]
[ 700.361235] [<f8ab522b>] bcm_can_tx+0x9d/0xd9 [can_bcm]
[ 700.361245] [<f8ab597f>] bcm_tx_timeout_handler+0x6a/0xbc [can_bcm]
[ 700.361255] [<f8ab5915>] bcm_tx_timeout_handler+0x0/0xbc [can_bcm]
[ 700.361263] [<c0134143>] __run_hrtimer+0x5a/0x86
[ 700.361273] [<f8ab5915>] bcm_tx_timeout_handler+0x0/0xbc [can_bcm]
[ 700.361282] [<c0134a50>] hrtimer_interrupt+0xb9/0x110
This patch moves the rest of the functionality from the hrtimer
callback to the already existing tasklet to fix this slowpath problem.
Signed-off-by: Oliver Hartkopp <oliver@hartkopp.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
The AF_CAN core delivered always cloned sk_buffs to the AF_CAN
protocols, although this was _only_ needed by the can-raw protocol.
With this (additionally documented) change, the AF_CAN core calls the
callback functions of the registered AF_CAN protocols with the original
(uncloned) sk_buff pointer and let's the can-raw protocol do the
skb_clone() itself which omits all unneeded skb_clone() calls for other
AF_CAN protocols.
Signed-off-by: Oliver Hartkopp <oliver@hartkopp.net>
Signed-off-by: Urs Thuermann <urs.thuermann@volkswagen.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
Since commit ca109491f6 ("hrtimer:
removing all ur callback modes") the hrtimer callbacks are processed
only in hardirq context.
This patch moves some functionality into tasklets to run in softirq
context.
Additionally some duplicated code was removed in bcm_rx_thr_flush()
and an avoidable memcpy was removed from bcm_rx_handler().
Signed-off-by: Oliver Hartkopp <oliver@hartkopp.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Due to a wrong safety check in af_can.c it was not possible to filter
for SFF frames with a specific CAN identifier without getting the
same selected CAN identifier from a received EFF frame also.
This fix has a minimum (but user visible) impact on the CAN filter
API and therefore the CAN version is set to a new date.
Indeed the 'old' API is still working as-is. But when now setting
CAN_(EFF|RTR)_FLAG in can_filter.can_mask you might get less traffic
than before - but still the stuff that you expected to get for your
defined filter ...
Thanks to Kurt Van Dijck for pointing at this issue and for the review.
Signed-off-by: Oliver Hartkopp <oliver@hartkopp.net>
Acked-by: Kurt Van Dijck <kurt.van.dijck@eia.be>
Signed-off-by: David S. Miller <davem@davemloft.net>
Without CONFIG_NET_NS, namespace is always &init_net.
Compiler will be able to omit namespace comparisons with this patch.
Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Even though the CAN netlayer only deals with CAN netdevices, the
netlayer interface to the userspace and to the device layer should
perform some sanity checks.
This patch adds several sanity checks that mainly prevent userspace apps
to send broken content into the system that may be misinterpreted by
some other userspace application.
Signed-off-by: Oliver Hartkopp <oliver.hartkopp@volkswagen.de>
Signed-off-by: Urs Thuermann <urs.thuermann@volkswagen.de>
Acked-by: Andre Naujoks <nautsch@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The helper function hrtimer_callback_running() is used in
kernel/hrtimer.c as well as in the updated net/can/bcm.c which now
supports hrtimers. Moving the helper function to hrtimer.h removes the
duplicate definition in the C-files.
Signed-off-by: Oliver Hartkopp <oliver@hartkopp.net>
Cc: David Miller <davem@davemloft.net>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Make use of hrtimers to support high resolution capabilities, when
provided by the system clocksource.
The conversion to hrtimers additionally discovered and solved an
unlikely race condition that has been reproduced under (unrealistic)
massive receive load, which can only be produced on vcan software devices.
[ Fix printf format warnings on 64-bit -DaveM ]
Signed-off-by: Oliver Hartkopp <oliver@hartkopp.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Introduce per-net_device inlines: dev_net(), dev_net_set().
Without CONFIG_NET_NS, no namespace other than &init_net exists.
Let's explicitly define them to help compiler optimizations.
Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
This patch adds the CAN broadcast manager (bcm) protocol.
Signed-off-by: Oliver Hartkopp <oliver.hartkopp@volkswagen.de>
Signed-off-by: Urs Thuermann <urs.thuermann@volkswagen.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
