linux-toradex.git/drivers/net/ppp, branch v3.16-rc2

inetpeer: get rid of ip_id_count

2014-06-02T18:00:41+00:00

Ideally, we would need to generate IP ID using a per destination IP
generator.

linux kernels used inet_peer cache for this purpose, but this had a huge
cost on servers disabling MTU discovery.

1) each inet_peer struct consumes 192 bytes

2) inetpeer cache uses a binary tree of inet_peer structs,
   with a nominal size of ~66000 elements under load.

3) lookups in this tree are hitting a lot of cache lines, as tree depth
   is about 20.

4) If server deals with many tcp flows, we have a high probability of
   not finding the inet_peer, allocating a fresh one, inserting it in
   the tree with same initial ip_id_count, (cf secure_ip_id())

5) We garbage collect inet_peer aggressively.

IP ID generation do not have to be 'perfect'

Goal is trying to avoid duplicates in a short period of time,
so that reassembly units have a chance to complete reassembly of
fragments belonging to one message before receiving other fragments
with a recycled ID.

We simply use an array of generators, and a Jenkin hash using the dst IP
as a key.

ipv6_select_ident() is put back into net/ipv6/ip6_output.c where it
belongs (it is only used from this file)

secure_ip_id() and secure_ipv6_id() no longer are needed.

Rename ip_select_ident_more() to ip_select_ident_segs() to avoid
unnecessary decrement/increment of the number of segments.

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

net: filter: let unattached filters use sock_fprog_kern

2014-05-23T20:48:05+00:00

The sk_unattached_filter_create() API is used by BPF filters that
are not directly attached or related to sockets, and are used in
team, ptp, xt_bpf, cls_bpf, etc. As such all users do their own
internal managment of obtaining filter blocks and thus already
have them in kernel memory and set up before calling into
sk_unattached_filter_create(). As a result, due to __user annotation
in sock_fprog, sparse triggers false positives (incorrect type in
assignment [different address space]) when filters are set up before
passing them to sk_unattached_filter_create(). Therefore, let
sk_unattached_filter_create() API use sock_fprog_kern to overcome
this issue.

Signed-off-by: Daniel Borkmann 
Acked-by: Alexei Starovoitov 
Signed-off-by: David S. Miller

net: ppp: use sk_unattached_filter api

2014-03-31T04:45:09+00:00

For the ppp driver, there are currently two open-coded BPF filters in use,
that is, pass_filter and active_filter. Migrate both to make proper use
of sk_unattached_filter_{create,destroy} API so that the actual BPF code
is decoupled from direct access, and filters can be jited as a side-effect
by the internal filter compiler.

Joint work with Alexei Starovoitov.

Signed-off-by: Daniel Borkmann 
Signed-off-by: Alexei Starovoitov 
Cc: Paul Mackerras 
Cc: linux-ppp@vger.kernel.org
Signed-off-by: David S. Miller

ppp: slight optimization of addr compare

2013-12-26T18:31:33+00:00

Use possibly more efficient ether_addr_equal
to instead of memcmp.

Cc: Michal Ostrowski 
Cc: netdev@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ding Tianhong 
Signed-off-by: David S. Miller

drivers/net/*: Fix FSF address in file headers

2013-12-06T17:37:55+00:00

Several files refer to an old address for the Free Software Foundation
in the file header comment.  Resolve by replacing the address with
the URL  so that we do not have to keep
updating the header comments anytime the address changes.

CC: Jay Vosburgh 
CC: Veaceslav Falico 
CC: Andy Gospodarek 
CC: Haiyang Zhang 
CC: "K. Y. Srinivasan" 
CC: Paul Mackerras 
CC: Ian Campbell 
CC: Wei Liu 
CC: Rusty Russell 
CC: "Michael S. Tsirkin" 
Signed-off-by: Jeff Kirsher 
Acked-by: Wei Liu 
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

ip: generate unique IP identificator if local fragmentation is allowed

2013-09-19T18:11:15+00:00

If local fragmentation is allowed, then ip_select_ident() and
ip_select_ident_more() need to generate unique IDs to ensure
correct defragmentation on the peer.

For example, if IPsec (tunnel mode) has to encrypt large skbs
that have local_df bit set, then all IP fragments that belonged
to different ESP datagrams would have used the same identificator.
If one of these IP fragments would get lost or reordered, then
peer could possibly stitch together wrong IP fragments that did
not belong to the same datagram. This would lead to a packet loss
or data corruption.

Signed-off-by: Ansis Atteka 
Signed-off-by: David S. Miller

pptp: fix byte order warnings

2013-08-13T22:10:22+00:00

Pptp driver has lots of byte order warnings from sparse.
This was because the on-the-wire header is in network byte order (obviously)
but the definition did not reflect that.

Also, the address structure to user space actually put the call id
in host order. Rather than break ABI compatibility, just acknowledge
the existing design.

Signed-off-by: Stephen Hemminger 
Signed-off-by: David S. Miller

pptp: fix sparse pointer warning

2013-08-09T21:14:50+00:00

callid_sock array is referenced via rcu_dereference and
sparse rcu checks complains about address space mismatch.

Signed-off-by: Stephen Hemminger 
Signed-off-by: David S. Miller

net: pass info struct via netdevice notifier

2013-05-28T20:11:01+00:00

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: Jiri Pirko 

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: David S. Miller