ip6_blackhole_route() does not initialize the newly allocated
rt6_info properly. This patch:
1. Call rt6_info_init() to initialize rt6i_siblings and rt6i_uncached
2. The current rt->dst._metrics init code is incorrect:
- 'rt->dst._metrics = ort->dst._metris' is not always safe
- Not sure what dst_copy_metrics() is trying to do here
considering ip6_rt_blackhole_cow_metrics() always returns
NULL
Fix:
- Always do dst_copy_metrics()
- Replace ip6_rt_blackhole_cow_metrics() with
dst_cow_metrics_generic()
3. Mask out the RTF_PCPU bit from the newly allocated blackhole route.
This bug triggers an oops (reported by Phil Sutter) in rt6_get_cookie().
It is because RTF_PCPU is set while rt->dst.from is NULL.
Fixes: d52d3997f8 ("ipv6: Create percpu rt6_info")
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Reported-by: Phil Sutter <phil@nwl.cc>
Tested-by: Phil Sutter <phil@nwl.cc>
Cc: Hannes Frederic Sowa <hannes@stressinduktion.org>
Cc: Julian Anastasov <ja@ssi.bg>
Cc: Phil Sutter <phil@nwl.cc>
Cc: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
0a1f596200