Package: ntp
Version: 1:4.2.6.p5+dfsg-7
Followup-For: Bug #795315
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Dear Maintainer,
looking a bit further at the code, I believe I now understand what
goes wrong: The process_routing_msgs(), which is called indirectly
inside the list loopi, could end up deleting and freeing(!) the
list entry currently being processed ("reader" points to it):
if (disable_dynamic_updates) {
/*
* discard ourselves if we are not needed any more
* usually happens when running unprivileged
*/
remove_asyncio_reader(reader);
delete_asyncio_reader(reader);
return;
}
cnt = read(reader->fd, buffer, sizeof(buffer));
if (cnt < 0) {
msyslog(LOG_ERR,
"i/o error on routing socket %m - disabling");
remove_asyncio_reader(reader);
delete_asyncio_reader(reader);
return;
}
Correlating that with my logs, I see that this is exactly what happened
to me:
Aug 12 14:55:49 canardo ntpd[31599]: i/o error on routing socket No buffer
space available - disabling
Aug 12 17:11:49 canardo ntpd[4566]: i/o error on routing socket No buffer space
available - disabling
Aug 12 17:36:49 canardo ntpd[15501]: i/o error on routing socket No buffer
space available - disabling
Aug 12 21:08:49 canardo ntpd[19058]: i/o error on routing socket No buffer
space available - disabling
Aug 12 21:32:49 canardo ntpd[2638]: i/o error on routing socket No buffer space
available - disabling
I don't know exactly how to fix this mess, but it is quite obvious that you
cannot free the "reader" element and then try to dereference it...
Bjørn
- -- System Information:
Debian Release: 8.1
APT prefers stable
APT policy: (990, 'stable'), (500, 'stable-updates')
Architecture: amd64 (x86_64)
Kernel: Linux 3.16.0-4-amd64 (SMP w/4 CPU cores)
Locale: LANG=en_US.UTF-8, LC_CTYPE=en_US.UTF-8 (charmap=UTF-8)
Shell: /bin/sh linked to /bin/dash
Init: sysvinit (via /sbin/init)
Versions of packages ntp depends on:
ii adduser 3.113+nmu3
ii dpkg 1.17.25
ii libc6 2.19-18
ii libcap2 1:2.24-8
ii libedit2 3.1-20140620-2
ii libopts25 1:5.18.4-3
ii libssl1.0.0 1.0.1k-3+deb8u1
ii lsb-base 4.1+Debian13+nmu1
ii netbase 5.3
Versions of packages ntp recommends:
ii perl 5.20.2-3+deb8u1
Versions of packages ntp suggests:
pn ntp-doc <none>
- -- Configuration Files:
/etc/ntp.conf changed [not included]
- -- no debconf information
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