dcdfa50eef
Stefano Brivio says:
====================
Fix listing (IPv4, IPv6) and flushing (IPv6) of cached route exceptions
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) and by retrieving and dumping cached routes if requested.
If strict checking is not requested (iproute2 < 5.0.0), we don't have a
way to consistently filter results on other selectors (e.g. on tables),
so skip filtering entirely and dump both regular routes and exceptions.
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 + + + +
v7: Make sure r->rtm_tos is initialised in 3/11, move loop over nexthop
objects in 4/11, add comments about usage of "skip" counters in commit
messages of 4/11 and 8/11
v6: Target for net-next, rebase and adapt to nexthop objects for IPv6 paths.
Merge selftests into this series (as they were addressed for net-next).
A number of minor changes detailed in logs of single patches.
v5: Skip filtering altogether if no strict checking is requested: selecting
routes or exceptions only would be inconsistent with the fact we can't
filter on tables. Drop 1/8 (non-strict dump filter function no longer
needed), replace 2/8 (don't use NLM_F_MATCH, decide to skip routes or
exceptions in filter function), drop 6/8 (2/8 is enough for IPv6 too).
Introduce dump_routes and dump_exceptions flags in filter, adapt other
patches to that.
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.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Linux kernel
============
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