On Tue, 2014-06-10 at 21:16 -0700, dormando wrote:

Ran our udpkill util against 3.10.42 with both of your patches applied...
seems like it ran a bit longer than normally would with this test (15-20
minutes), then died:

Well, could you try a recent kernel instead ?

I can see some races and fixes are probably worth it.

$ git log --oneline v3.10.42..v3.15 net/ipv4/route.c
fbdc0ad ipv4: initialise the itag variable in __mkroute_input
0d5edc6 ipv4, route: pass 0 instead of LOOPBACK_IFINDEX to fib_validate_source()
aad8872 ipv4: add a sock pointer to dst->output() path.
9114615 ipv4: return valid RTA_IIF on ip route get
3ed66e9 net: replace __this_cpu_inc in route.c with raw_cpu_inc
0b8c7f6 ipv4: remove ip_rt_dump from route.c
4a4eb21 ipv4: remove ipv4_ifdown_dst from route.c
1e8d642 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
a625486 ipv4: fix counter in_slow_tot
cd0f0b9 ipv4: distinguish EHOSTUNREACH from the ENETUNREACH
2045cea net: remove unnecessary return's
f87c10a ipv4: introduce ip_dst_mtu_maybe_forward and protect forwarding path against pmtu spoofing
dcdfdf5 ipv4: fix race in concurrent ip_route_input_slow()
482fc60 ipv4: introduce new IP_MTU_DISCOVER mode IP_PMTUDISC_INTERFACE
0baf2b3 ipv4: shrink rt_cache_stat
0a7e226 ipv4: fix ineffective source address selection
734d272 ipv4: raise IP_MAX_MTU to theoretical limit
ca4c3fc net: split rt_genid for ipv4 and ipv6
2ffae99 ipv4: use next hop exceptions also for input routes
fe2c633 net: Convert uses of typedef ctl_table to struct ctl_table
6bc19fb Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
5aad1de ipv4: use separate genid for next hop exceptions
f016229 ipv4: rate limit updating of next hop exceptions with same pmtu
387aa65 ipv4: properly refresh rtable entries on pmtu/redirect events