For IPv6 cached routes, the commands 'ip -6 route list cache' and
'ip -6 route flush cache' don't work at all after route exceptions have
been moved to a separate hash table in commit 2b760fcf5cfb ("ipv6: hook
up exception table to store dst cache").
For IPv4 cached routes, the command 'ip route list cache' has also
stopped working in kernel 3.5 after commit 4895c771c7f0 ("ipv4: Add FIB
nexthop exceptions.") introduced storage for route exceptions as a
separate entity.
Fix this by allowing userspace to clearly request cached routes with
the RTM_F_CLONED flag used as a filter (in conjuction with strict
checking or NLM_F_MATCH) and by retrieving and dumping cached routes
if requested.
I'm submitting this for net as these changes fix rather relevant
breakages. However, the scope might be a bit broad, and said breakages
have been introduced 7 and 2 years ago, respectively, for IPv4 and IPv6.
Let me know if I should rebase this on net-next instead.
For IPv4, cache flushing uses a completely different mechanism, so it
wasn't affected. Listing of exception routes (modified routes pre-3.5) was
tested against these versions of kernel and iproute2:
iproute2
kernel 4.14.0 4.15.0 4.19.0 5.0.0 5.1.0
3.5-rc4 + + + + +
4.4
4.9
4.14
4.15
4.19
5.0
5.1
fixed + + + + +
For IPv6, a separate iproute2 patch is required. Versions of iproute2
and kernel tested:
iproute2
kernel 4.14.0 4.15.0 4.19.0 5.0.0 5.1.0 5.1.0, patched
3.18 list + + + + + +
flush + + + + + +
4.4 list + + + + + +
flush + + + + + +
4.9 list + + + + + +
flush + + + + + +
4.14 list + + + + + +
flush + + + + + +
4.15 list
flush
4.19 list
flush
5.0 list
flush
5.1 list
flush
with list + + + + + +
fix flush +
v4: Fix the listing issue also for IPv4, making the behaviour consistent
with IPv6. Honour NLM_F_MATCH as per RFC 3549 and allow usage of
RTM_F_CLONED filter. Split patches into smaller logical changes.
v3: Drop check on RTM_F_CLONED and rework logic of return values of
rt6_dump_route()
v2: Add count of routes handled in partial dumps, and skip them, in patch 1/2.
*** BLURB HERE ***
Stefano Brivio (8):
ipv4/fib_frontend: Rename ip_valid_fib_dump_req, provide non-strict
version
ipv4: Honour NLM_F_MATCH, make semantics of NETLINK_GET_STRICT_CHK
consistent
ipv4/fib_frontend: Allow RTM_F_CLONED flag to be used for filtering
ipv4: Dump routed caches if requested
Revert "net/ipv6: Bail early if user only wants cloned entries"
ipv6: Honour NLM_F_MATCH, make semantics of NETLINK_GET_STRICT_CHK
consistent
ipv6: Dump route exceptions too in rt6_dump_route()
ip6_fib: Don't discard nodes with valid routing information in
fib6_locate_1()
include/net/ip6_fib.h | 1 +
include/net/ip6_route.h | 2 +-
include/net/ip_fib.h | 6 +--
include/net/route.h | 3 ++
net/ipv4/fib_frontend.c | 50 ++++++++++++-------
net/ipv4/fib_trie.c | 103 +++++++++++++++++++++++++++++++++++-----
net/ipv4/ipmr.c | 4 +-
net/ipv4/route.c | 6 +--
net/ipv6/ip6_fib.c | 37 ++++++++++-----
net/ipv6/ip6mr.c | 4 +-
net/ipv6/route.c | 74 ++++++++++++++++++++++++++---
net/mpls/af_mpls.c | 2 +-
12 files changed, 230 insertions(+), 62 deletions(-)
--
2.20.1
