kernel/linux.git/include/net/inetpeer.h, branch v3.4.112

inetpeer: get rid of ip_id_count

2014-08-14T00:42:35+00:00

[ Upstream commit 73f156a6e8c1074ac6327e0abd1169e95eb66463 ] 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 Signed-off-by: Greg Kroah-Hartman

net: fix inet_getid() and ipv6_select_ident() bugs

2014-06-26T19:10:28+00:00

[ Upstream commit 39c36094d78c39e038c1e499b2364e13bce36f54 ] I noticed we were sending wrong IPv4 ID in TCP flows when MTU discovery is disabled. Note how GSO/TSO packets do not have monotonically incrementing ID. 06:37:41.575531 IP (id 14227, proto: TCP (6), length: 4396) 06:37:41.575534 IP (id 14272, proto: TCP (6), length: 65212) 06:37:41.575544 IP (id 14312, proto: TCP (6), length: 57972) 06:37:41.575678 IP (id 14317, proto: TCP (6), length: 7292) 06:37:41.575683 IP (id 14361, proto: TCP (6), length: 63764) It appears I introduced this bug in linux-3.1. inet_getid() must return the old value of peer->ip_id_count, not the new one. Lets revert this part, and remove the prevention of a null identification field in IPv6 Fragment Extension Header, which is dubious and not even done properly. Fixes: 87c48fa3b463 ("ipv6: make fragment identifications less predictable") Signed-off-by: Eric Dumazet Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

inetpeer: fix a race in inetpeer_gc_worker()

2012-07-16T16:03:45+00:00

[ Upstream commit 55432d2b543a4b6dfae54f5c432a566877a85d90 ] commit 5faa5df1fa2024 (inetpeer: Invalidate the inetpeer tree along with the routing cache) added a race : Before freeing an inetpeer, we must respect a RCU grace period, and make sure no user will attempt to increase refcnt. inetpeer_invalidate_tree() waits for a RCU grace period before inserting inetpeer tree into gc_list and waking the worker. At that time, no concurrent lookup can find a inetpeer in this tree. Signed-off-by: Eric Dumazet Cc: Steffen Klassert Acked-by: Steffen Klassert Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

route: Remove redirect_genid

2012-03-08T08:30:32+00:00

As we invalidate the inetpeer tree along with the routing cache now, we don't need a genid to reset the redirect handling when the routing cache is flushed. Signed-off-by: Steffen Klassert Signed-off-by: David S. Miller

inetpeer: Invalidate the inetpeer tree along with the routing cache

2012-03-08T08:30:24+00:00

We initialize the routing metrics with the values cached on the inetpeer in rt_init_metrics(). So if we have the metrics cached on the inetpeer, we ignore the user configured fib_metrics. To fix this issue, we replace the old tree with a fresh initialized inet_peer_base. The old tree is removed later with a delayed work queue. Signed-off-by: Steffen Klassert Signed-off-by: David S. Miller

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

2011-12-02T18:49:21+00:00

inet: add a redirect generation id in inetpeer

2011-11-27T00:16:37+00:00

Now inetpeer is the place where we cache redirect information for ipv4 destinations, we must be able to invalidate informations when a route is added/removed on host. As inetpeer is not yet namespace aware, this patch adds a shared redirect_genid, and a per inetpeer redirect_genid. This might be changed later if inetpeer becomes ns aware. Cache information for one inerpeer is valid as long as its redirect_genid has the same value than global redirect_genid. Reported-by: Arkadiusz Miśkiewicz Tested-by: Arkadiusz Miśkiewicz Signed-off-by: Eric Dumazet Signed-off-by: David S. Miller

net: remove ipv6_addr_copy()

2011-11-22T21:43:32+00:00

C assignment can handle struct in6_addr copying. Signed-off-by: Alexey Dobriyan Signed-off-by: David S. Miller

atomic: use

2011-07-26T23:49:47+00:00

This allows us to move duplicated code in (atomic_inc_not_zero() for now) to Signed-off-by: Arun Sharma Reviewed-by: Eric Dumazet Cc: Ingo Molnar Cc: David Miller Cc: Eric Dumazet Acked-by: Mike Frysinger Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

ipv6: make fragment identifications less predictable

2011-07-22T04:25:58+00:00

IPv6 fragment identification generation is way beyond what we use for IPv4 : It uses a single generator. Its not scalable and allows DOS attacks. Now inetpeer is IPv6 aware, we can use it to provide a more secure and scalable frag ident generator (per destination, instead of system wide) This patch : 1) defines a new secure_ipv6_id() helper 2) extends inet_getid() to provide 32bit results 3) extends ipv6_select_ident() with a new dest parameter Reported-by: Fernando Gont Signed-off-by: Eric Dumazet Signed-off-by: David S. Miller