linux-stable.git/net/packet, branch v3.13.2

packet: fix send path when running with proto == 0

2013-12-10T01:09:20+00:00

Commit e40526cb20b5 introduced a cached dev pointer, that gets
hooked into register_prot_hook(), __unregister_prot_hook() to
update the device used for the send path.

We need to fix this up, as otherwise this will not work with
sockets created with protocol = 0, plus with sll_protocol = 0
passed via sockaddr_ll when doing the bind.

So instead, assign the pointer directly. The compiler can inline
these helper functions automagically.

While at it, also assume the cached dev fast-path as likely(),
and document this variant of socket creation as it seems it is
not widely used (seems not even the author of TX_RING was aware
of that in his reference example [1]). Tested with reproducer
from e40526cb20b5.

 [1] http://wiki.ipxwarzone.com/index.php5?title=Linux_packet_mmap#Example

Fixes: e40526cb20b5 ("packet: fix use after free race in send path when dev is released")
Signed-off-by: Daniel Borkmann 
Tested-by: Salam Noureddine 
Tested-by: Jesper Dangaard Brouer 
Signed-off-by: David S. Miller

af_packet: block BH in prb_shutdown_retire_blk_timer()

2013-11-29T21:11:08+00:00

Currently we're using plain spin_lock() in prb_shutdown_retire_blk_timer(),
however the timer might fire right in the middle and thus try to re-aquire
the same spinlock, leaving us in a endless loop.

To fix that, use the spin_lock_bh() to block it.

Fixes: f6fb8f100b80 ("af-packet: TPACKET_V3 flexible buffer implementation.")
CC: "David S. Miller" 
CC: Daniel Borkmann 
CC: Willem de Bruijn 
CC: Phil Sutter 
CC: Eric Dumazet 
Reported-by: Jan Stancek 
Tested-by: Jan Stancek 
Signed-off-by: Veaceslav Falico 
Acked-by: Daniel Borkmann 
Signed-off-by: David S. Miller

packet: fix use after free race in send path when dev is released

2013-11-21T18:09:43+00:00

Salam reported a use after free bug in PF_PACKET that occurs when
we're sending out frames on a socket bound device and suddenly the
net device is being unregistered. It appears that commit 827d9780
introduced a possible race condition between {t,}packet_snd() and
packet_notifier(). In the case of a bound socket, packet_notifier()
can drop the last reference to the net_device and {t,}packet_snd()
might end up suddenly sending a packet over a freed net_device.

To avoid reverting 827d9780 and thus introducing a performance
regression compared to the current state of things, we decided to
hold a cached RCU protected pointer to the net device and maintain
it on write side via bind spin_lock protected register_prot_hook()
and __unregister_prot_hook() calls.

In {t,}packet_snd() path, we access this pointer under rcu_read_lock
through packet_cached_dev_get() that holds reference to the device
to prevent it from being freed through packet_notifier() while
we're in send path. This is okay to do as dev_put()/dev_hold() are
per-cpu counters, so this should not be a performance issue. Also,
the code simplifies a bit as we don't need need_rls_dev anymore.

Fixes: 827d978037d7 ("af-packet: Use existing netdev reference for bound sockets.")
Reported-by: Salam Noureddine 
Signed-off-by: Daniel Borkmann 
Signed-off-by: Salam Noureddine 
Cc: Ben Greear 
Cc: Eric Dumazet 
Signed-off-by: David S. Miller

net: rework recvmsg handler msg_name and msg_namelen logic

2013-11-21T02:52:30+00:00

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 
Suggested-by: Eric Dumazet 
Signed-off-by: Hannes Frederic Sowa 
Signed-off-by: David S. Miller

net: packet: use reciprocal_divide in fanout_demux_hash

2013-08-29T20:43:29+00:00

Instead of hard-coding reciprocal_divide function, use the inline
function from reciprocal_div.h.

Signed-off-by: Daniel Borkmann 
Signed-off-by: David S. Miller

net: packet: add randomized fanout scheduler

2013-08-29T20:43:29+00:00

We currently allow for different fanout scheduling policies in pf_packet
such as scheduling by skb's rxhash, round-robin, by cpu, and rollover.
Also allow for a random, equidistributed selection of the socket from the
fanout process group.

Signed-off-by: Daniel Borkmann 
Signed-off-by: David S. Miller

Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net

2013-08-26T20:37:08+00:00

Conflicts:
	drivers/net/wireless/iwlwifi/pcie/trans.c
	include/linux/inetdevice.h

The inetdevice.h conflict involves moving the IPV4_DEVCONF values
into a UAPI header, overlapping additions of some new entries.

The iwlwifi conflict is a context overlap.

Signed-off-by: David S. Miller

packet: restore packet statistics tp_packets to include drops

2013-08-21T00:23:58+00:00

getsockopt PACKET_STATISTICS returns tp_packets + tp_drops. Commit
ee80fbf301 ("packet: account statistics only in tpacket_stats_u")
cleaned up the getsockopt PACKET_STATISTICS code.
This also changed semantics. Historically, tp_packets included
tp_drops on return. The commit removed the line that adds tp_drops
into tp_packets.

This patch reinstates the old semantics.

Signed-off-by: Willem de Bruijn 
Acked-by: Daniel Borkmann 
Signed-off-by: David S. Miller

net: attempt high order allocations in sock_alloc_send_pskb()

2013-08-10T08:16:44+00:00

Adding paged frags skbs to af_unix sockets introduced a performance
regression on large sends because of additional page allocations, even
if each skb could carry at least 100% more payload than before.

We can instruct sock_alloc_send_pskb() to attempt high order
allocations.

Most of the time, it does a single page allocation instead of 8.

I added an additional parameter to sock_alloc_send_pskb() to
let other users to opt-in for this new feature on followup patches.

Tested:

Before patch :

$ netperf -t STREAM_STREAM
STREAM STREAM TEST
Recv   Send    Send
Socket Socket  Message  Elapsed
Size   Size    Size     Time     Throughput
bytes  bytes   bytes    secs.    10^6bits/sec

 2304  212992  212992    10.00    46861.15

After patch :

$ netperf -t STREAM_STREAM
STREAM STREAM TEST
Recv   Send    Send
Socket Socket  Message  Elapsed
Size   Size    Size     Time     Throughput
bytes  bytes   bytes    secs.    10^6bits/sec

 2304  212992  212992    10.00    57981.11

Signed-off-by: Eric Dumazet 
Cc: David Rientjes 
Signed-off-by: David S. Miller

packet: Revert recent header parsing changes.

2013-08-08T00:11:00+00:00

This reverts commits:

0f75b09c798ed00c30d7d5551b896be883bc2aeb
cbd89acb9eb257ed3b2be867142583fdcf7fdc5b
c483e02614551e44ced3fe6eedda8e36d3277ccc

Amongst other things, it's modifies the SKB header
to pull the ethernet headers off via eth_type_trans()
on the output path which is bogus.

It's causing serious regressions for people.

Signed-off-by: David S. Miller