I also noticed the situation can be reproduced at boot if the value of "net.core.rmem_default" is too low.
I reproduced it by only lowering the "net.core.rmem_default = 2000" value with 6 network interface at boot. ntpd[851]: ntp_io: estimated max descriptors: 1024, initial socket boundary: 16 ntpd[851]: Listen and drop on 0 v4wildcard 0.0.0.0 UDP 123 ntpd[851]: Listen and drop on 1 v6wildcard :: UDP 123 ntpd[851]: Listen normally on 2 eth1 192.168.1.10 UDP 123 ntpd[851]: Listen normally on 3 eth2 192.168.2.10 UDP 123 ntpd[851]: Listen normally on 4 eth3 192.168.3.10 UDP 123 ntpd[851]: Listen normally on 5 eth4 192.168.4.10 UDP 123 ntpd[851]: Listen normally on 6 eth5 192.168.5.10 UDP 123 ntpd[851]: Listen normally on 7 eth6 192.168.6.10 UDP 123 ntpd[851]: peers refreshed ntpd[851]: Listening on routing socket on fd #24 for interface updates ntpd[851]: Deferring DNS for 0.ubuntu.pool.ntp.org 1 ntpd[851]: Deferring DNS for 1.ubuntu.pool.ntp.org 1 ntpd[851]: Deferring DNS for 2.ubuntu.pool.ntp.org 1 ntpd[851]: Deferring DNS for 3.ubuntu.pool.ntp.org 1 ntpd[851]: Deferring DNS for ntp.ubuntu.com 1 ntpd[864]: signal_no_reset: signal 17 had flags 4000000 ===> ntpd[851]: i/o error on routing socket No buffer space available - disabling <=== -- You received this bug notification because you are a member of Ubuntu Server Team, which is subscribed to the bug report. https://bugs.launchpad.net/bugs/1481388 Title: NTP : Use-after-free in routing socket code after dropping root To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/ntp/+bug/1481388/+subscriptions -- Ubuntu-server-bugs mailing list Ubuntu-server-bugs@lists.ubuntu.com Modify settings or unsubscribe at: https://lists.ubuntu.com/mailman/listinfo/ubuntu-server-bugs
