linux.git/net/ipv6/ip6_fib.c, branch v5.0

ipv6: Fix dump of specific table with strict checking

2019-01-03T04:15:43+00:00

Dump of a specific table with strict checking enabled is looping. The
problem is that the end of the table dump is not marked in the cb. When
dumping a specific table, cb args 0 and 1 are not used (they are the hash
index and entry with an hash table index when dumping all tables). Re-use
args[0] to hold a 'done' flag for the specific table dump.

Fixes: 13e38901d46ca ("net/ipv6: Plumb support for filtering route dumps")
Reported-by: Jakub Kicinski 
Signed-off-by: David Ahern 
Signed-off-by: David S. Miller

ipv6: properly check return value in inet6_dump_all()

2018-11-06T01:04:54+00:00

Make sure we call fib6_dump_end() if it happens that skb->len
is zero. rtnl_dump_all() can reset cb->args on the next loop
iteration there.

Fixes: 08e814c9e8eb ("net/ipv6: Bail early if user only wants cloned entries")
Fixes: ae677bbb4441 ("net: Don't return invalid table id error when dumping all families")
Signed-off-by: Alexey Kodanev 
Signed-off-by: David S. Miller

net: Don't return invalid table id error when dumping all families

2018-10-24T21:06:25+00:00

When doing a route dump across all address families, do not error out
if the table does not exist. This allows a route dump for AF_UNSPEC
with a table id that may only exist for some of the families.

Do return the table does not exist error if dumping routes for a
specific family and the table does not exist.

Signed-off-by: David Ahern 
Signed-off-by: David S. Miller

net/ipv6: Bail early if user only wants cloned entries

2018-10-16T07:14:07+00:00

Similar to IPv4, IPv6 fib no longer contains cloned routes. If a user
requests a route dump for only cloned entries, no sense walking the FIB
and returning everything.

Signed-off-by: David Ahern 
Signed-off-by: David S. Miller

net: Enable kernel side filtering of route dumps

2018-10-16T07:14:07+00:00

Update parsing of route dump request to enable kernel side filtering.
Allow filtering results by protocol (e.g., which routing daemon installed
the route), route type (e.g., unicast), table id and nexthop device. These
amount to the low hanging fruit, yet a huge improvement, for dumping
routes.

ip_valid_fib_dump_req is called with RTNL held, so __dev_get_by_index can
be used to look up the device index without taking a reference. From
there filter->dev is only used during dump loops with the lock still held.

Set NLM_F_DUMP_FILTERED in the answer_flags so the user knows the results
have been filtered should no entries be returned.

Signed-off-by: David Ahern 
Signed-off-by: David S. Miller

net/ipv6: Plumb support for filtering route dumps

2018-10-16T07:13:12+00:00

Implement kernel side filtering of routes by table id, egress device
index, protocol, and route type. If the table id is given in the filter,
lookup the table and call fib6_dump_table directly for it.

Move the existing route flags check for prefix only routes to the new
filter.

Signed-off-by: David Ahern 
Signed-off-by: David S. Miller

net: Add struct for fib dump filter

2018-10-16T07:13:12+00:00

Add struct fib_dump_filter for options on limiting which routes are
returned in a dump request. The current list is table id, protocol,
route type, rtm_flags and nexthop device index. struct net is needed
to lookup the net_device from the index.

Declare the filter for each route dump handler and plumb the new
arguments from dump handlers to ip_valid_fib_dump_req.

Signed-off-by: David Ahern 
Signed-off-by: David S. Miller

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

2018-10-13T04:38:46+00:00

Conflicts were easy to resolve using immediate context mostly,
except the cls_u32.c one where I simply too the entire HEAD
chunk.

Signed-off-by: David S. Miller

net/ipv6: Add knob to skip DELROUTE message on device down

2018-10-12T16:47:02+00:00

Another difference between IPv4 and IPv6 is the generation of RTM_DELROUTE
notifications when a device is taken down (admin down) or deleted. IPv4
does not generate a message for routes evicted by the down or delete;
IPv6 does. A NOS at scale really needs to avoid these messages and have
IPv4 and IPv6 behave similarly, relying on userspace to handle link
notifications and evict the routes.

At this point existing user behavior needs to be preserved. Since
notifications are a global action (not per app) the only way to preserve
existing behavior and allow the messages to be skipped is to add a new
sysctl (net/ipv6/route/skip_notify_on_dev_down) which can be set to
disable the notificatioons.

IPv6 route code already supports the option to skip the message (it is
used for multipath routes for example). Besides the new sysctl we need
to pass the skip_notify setting through the generic fib6_clean and
fib6_walk functions to fib6_clean_node and to set skip_notify on calls
to __ip_del_rt for the addrconf_ifdown path.

Signed-off-by: David Ahern 
Signed-off-by: David S. Miller

net/ipv6: stop leaking percpu memory in fib6 info

2018-10-11T05:42:54+00:00

The fib6_info_alloc() function allocates percpu memory to hold per CPU
pointers to rt6_info, but this memory is never freed. Fix it.

Fixes: a64efe142f5e ("net/ipv6: introduce fib6_info struct and helpers")
Signed-off-by: Mike Rapoport 
Reviewed-by: David Ahern 
Signed-off-by: David S. Miller