linux-toradex.git/net/ipv4/route.c, branch v3.0.29

ipv4: fix redirect handling

2012-03-01T00:34:18+00:00

[ Upstream commit 9cc20b268a5a14f5e57b8ad405a83513ab0d78dc ]

commit f39925dbde77 (ipv4: Cache learned redirect information in
inetpeer.) introduced a regression in ICMP redirect handling.

It assumed ipv4_dst_check() would be called because all possible routes
were attached to the inetpeer we modify in ip_rt_redirect(), but thats
not true.

commit 7cc9150ebe (route: fix ICMP redirect validation) tried to fix
this but solution was not complete. (It fixed only one route)

So we must lookup existing routes (including different TOS values) and
call check_peer_redir() on them.

Reported-by: Ivan Zahariev 
Signed-off-by: Eric Dumazet 
CC: Flavio Leitner 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

route: fix ICMP redirect validation

2012-03-01T00:34:17+00:00

[ Upstream commit 7cc9150ebe8ec06cafea9f1c10d92ddacf88d8ae ]

The commit f39925dbde7788cfb96419c0f092b086aa325c0f
(ipv4: Cache learned redirect information in inetpeer.)
removed some ICMP packet validations which are required by
RFC 1122, section 3.2.2.2:
...
  A Redirect message SHOULD be silently discarded if the new
  gateway address it specifies is not on the same connected
  (sub-) net through which the Redirect arrived [INTRO:2,
  Appendix A], or if the source of the Redirect is not the
  current first-hop gateway for the specified destination (see
  Section 3.3.1).

Signed-off-by: Flavio Leitner 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

net: fix NULL dereferences in check_peer_redir()

2012-02-13T19:06:13+00:00

[ Upstream commit d3aaeb38c40e5a6c08dd31a1b64da65c4352be36, along
  with dependent backports of commits:
     69cce1d1404968f78b177a0314f5822d5afdbbfb
     9de79c127cccecb11ae6a21ab1499e87aa222880
     218fa90f072e4aeff9003d57e390857f4f35513e
     580da35a31f91a594f3090b7a2c39b85cb051a12
     f7e57044eeb1841847c24aa06766c8290c202583
     e049f28883126c689cf95859480d9ee4ab23b7fa ]

Gergely Kalman reported crashes in check_peer_redir().

It appears commit f39925dbde778 (ipv4: Cache learned redirect
information in inetpeer.) added a race, leading to possible NULL ptr
dereference.

Since we can now change dst neighbour, we should make sure a reader can
safely use a neighbour.

Add RCU protection to dst neighbour, and make sure check_peer_redir()
can be called safely by different cpus in parallel.

As neighbours are already freed after one RCU grace period, this patch
should not add typical RCU penalty (cache cold effects)

Many thanks to Gergely for providing a pretty report pointing to the
bug.

Reported-by: Gergely Kalman 
Signed-off-by: Eric Dumazet 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

ipv4: using prefetch requires including prefetch.h

2012-01-06T22:14:10+00:00

[ Upstream commit b9eda06f80b0db61a73bd87c6b0eb67d8aca55ad ]

Signed-off-by: Stephen Rothwell 
Acked-by: Eric Dumazet 
Acked-by: David Miller 
Signed-off-by: Linus Torvalds 
Signed-off-by: Greg Kroah-Hartman

ipv4: reintroduce route cache garbage collector

2012-01-06T22:14:10+00:00

[ Upstream commit 9f28a2fc0bd77511f649c0a788c7bf9a5fd04edb ]

Commit 2c8cec5c10b (ipv4: Cache learned PMTU information in inetpeer)
removed IP route cache garbage collector a bit too soon, as this gc was
responsible for expired routes cleanup, releasing their neighbour
reference.

As pointed out by Robert Gladewitz, recent kernels can fill and exhaust
their neighbour cache.

Reintroduce the garbage collection, since we'll have to wait our
neighbour lookups become refcount-less to not depend on this stuff.

Reported-by: Robert Gladewitz 
Signed-off-by: Eric Dumazet 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

ipv4: some rt_iif -> rt_route_iif conversions

2011-10-03T18:40:51+00:00

[ Upstream commit 97a804102021431fa6fa33c21c85df762b0f5cb9 ]

As rt_iif represents input device even for packets
coming from loopback with output route, it is not an unique
key specific to input routes. Now rt_route_iif has such role,
it was fl.iif in 2.6.38, so better to change the checks at
some places to save CPU cycles and to restore 2.6.38 semantics.

compare_keys:
	- input routes: only rt_route_iif matters, rt_iif is same
	- output routes: only rt_oif matters, rt_iif is not
		used for matching in __ip_route_output_key
	- now we are back to 2.6.38 state

ip_route_input_common:
	- matching rt_route_iif implies input route
	- compared to 2.6.38 we eliminated one rth->fl.oif check
	because it was not needed even for 2.6.38

compare_hash_inputs:
	Only the change here is not an optimization, it has
	effect only for output routes. I assume I'm restoring
	the original intention to ignore oif, it was using fl.iif
	- now we are back to 2.6.38 state

Signed-off-by: Julian Anastasov 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

ipv4: use RT_TOS after some rt_tos conversions

2011-08-16T01:31:39+00:00

[ Upstream commit b0fe4a31849063fcac0bdc93716ca92615e93f57 ]

rt_tos was changed to iph->tos but it must be filtered by RT_TOS

Signed-off-by: Julian Anastasov 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

ipv4: fix the reusing of routing cache entries

2011-08-16T01:31:37+00:00

[ Upstream commit d547f727df86059104af2234804fdd538e112015 ]

	compare_keys and ip_route_input_common rely on
rt_oif for distinguishing of input and output routes
with same keys values. But sometimes the input route has
also same hash chain (keyed by iif != 0) with the output
routes (keyed by orig_oif=0). Problem visible if running
with small number of rhash_entries.

	Fix them to use rt_route_iif instead. By this way
input route can not be returned to users that request
output route.

	The patch fixes the ip_rt_bug errors that were
reported in ip_local_out context, mostly for 255.255.255.255
destinations.

Signed-off-by: Julian Anastasov 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

net: Compute protocol sequence numbers and fragment IDs using MD5.

2011-08-16T01:31:35+00:00

Computers have become a lot faster since we compromised on the
partial MD4 hash which we use currently for performance reasons.

MD5 is a much safer choice, and is inline with both RFC1948 and
other ISS generators (OpenBSD, Solaris, etc.)

Furthermore, only having 24-bits of the sequence number be truly
unpredictable is a very serious limitation.  So the periodic
regeneration and 8-bit counter have been removed.  We compute and
use a full 32-bit sequence number.

For ipv6, DCCP was found to use a 32-bit truncated initial sequence
number (it needs 43-bits) and that is fixed here as well.

Reported-by: Dan Kaminsky 
Tested-by: Willy Tarreau 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

ipv4: fix multicast losses

2011-06-18T18:59:18+00:00

Knut Tidemann found that first packet of a multicast flow was not
correctly received, and bisected the regression to commit b23dd4fe42b4
(Make output route lookup return rtable directly.)

Special thanks to Knut, who provided a very nice bug report, including
sample programs to demonstrate the bug.

Reported-and-bisectedby: Knut Tidemann 
Signed-off-by: Eric Dumazet 
Signed-off-by: David S. Miller