debdiff for precise
** Description changed: + [Impact] + + * User experienced repeated segfaults at the same instruction pointer + + i/o error on routing socket No buffer space available - disabling + segfault at 31 ip 0000000000000031 sp 00007ffff9f11788 error 14 in libpthread-2.15.so[7f967a5d9000+18000] + + The remove_ and delete_ functions remove the current element from the + asyncio_reader_list, and free it, respectively. + + We then return back to the loop at the top, wherein the asyncio_reader variable still points at the now-freed element, whose contents are (in theory) now scrambled + by having link pointers, etc, from internal malloc state overlaying the data. + + [Test Case] + + You can easily reproduce the bug by : + + - Lowering the sysctl value net.core.rmem_max + + $ sysctl -w net.core.wmem_max=<LOWER_VALUE> + This sets the max OS send buffer size for all types of connections. + + - Adding multiple network interfaces and static routes. + + [Regression Potential] + + None expected since the fix is already available upstream + (https://github.com/ntp-project/ntp.git) and Debian package. + + If after installing the patch, user are receiving this kind of message in /var/log/syslog : "routing socket reports: No buffer space available". + The next step, would be to increase the "net.core.rmem_max" and "net.core.wmem_max" values equally until the "routing socket reports: No buffer space available" message no longer showed up. + + [Other Info] + + NTP upstream (https://github.com/ntp-project/ntp.git) + [Bug 2224] Use-after-free in routing socket code after dropping root. - Commit: d6df9d3 + [Bug 2890] Ignore ENOBUFS on routing netlink socket. - Commit: db47bd4 + + The use-after-free bug has been fix in Debian release (closes: #795315) + Will submit the ignore-ENOBUFS-on-routing-netlink-socket in Debian in the next days. + + [Original Description] + We have 1 server (among hundreds) that its ntp service is crashing. A few minute/seconds after a start attempts we can see the following in syslog: ntpd[2729]: peers refreshed ntpd[2729]: Listening on routing socket on fd #49 for interface updates ntpd[2729]: i/o error on routing socket No buffer space available - disabling kernel: [157516.495224] ntpd[2729]: segfault at 31 ip 0000000000000031 sp 00007ffff9f11788 error 14 in libpthread-2.15.so[7f967a5d9000+18000] OS: Ubuntu 12.04.4 LTS Kernel: 3.11.0-19-generic I tried to compare it to other servers, and the only thing I could find that is different is that while it's up (before it crashes) I can see the following when running "lsof | grep ntp": ntpd 2729 ntp 49u sock 0,7 0t0 2473952565 can't identify protocol. ** Tags added: verification-done ** Changed in: ntp (Ubuntu Precise) Status: Confirmed => In Progress -- You received this bug notification because you are a member of Ubuntu Touch seeded packages, which is subscribed to ntp in Ubuntu. https://bugs.launchpad.net/bugs/1481388 Title: NTP : Use-after-free in routing socket code after dropping root Status in ntp package in Ubuntu: Confirmed Status in ntp source package in Precise: In Progress Status in ntp source package in Trusty: Confirmed Status in ntp source package in Vivid: Confirmed Status in ntp source package in Wily: Confirmed Bug description: [Impact] * User experienced repeated segfaults at the same instruction pointer i/o error on routing socket No buffer space available - disabling segfault at 31 ip 0000000000000031 sp 00007ffff9f11788 error 14 in libpthread-2.15.so[7f967a5d9000+18000] The remove_ and delete_ functions remove the current element from the asyncio_reader_list, and free it, respectively. We then return back to the loop at the top, wherein the asyncio_reader variable still points at the now-freed element, whose contents are (in theory) now scrambled by having link pointers, etc, from internal malloc state overlaying the data. [Test Case] You can easily reproduce the bug by : - Lowering the sysctl value net.core.rmem_max $ sysctl -w net.core.wmem_max=<LOWER_VALUE> This sets the max OS send buffer size for all types of connections. - Adding multiple network interfaces and static routes. [Regression Potential] None expected since the fix is already available upstream (https://github.com/ntp-project/ntp.git) and Debian package. If after installing the patch, user are receiving this kind of message in /var/log/syslog : "routing socket reports: No buffer space available". The next step, would be to increase the "net.core.rmem_max" and "net.core.wmem_max" values equally until the "routing socket reports: No buffer space available" message no longer showed up. [Other Info] NTP upstream (https://github.com/ntp-project/ntp.git) [Bug 2224] Use-after-free in routing socket code after dropping root. - Commit: d6df9d3 [Bug 2890] Ignore ENOBUFS on routing netlink socket. - Commit: db47bd4 The use-after-free bug has been fix in Debian release (closes: #795315) Will submit the ignore-ENOBUFS-on-routing-netlink-socket in Debian in the next days. [Original Description] We have 1 server (among hundreds) that its ntp service is crashing. A few minute/seconds after a start attempts we can see the following in syslog: ntpd[2729]: peers refreshed ntpd[2729]: Listening on routing socket on fd #49 for interface updates ntpd[2729]: i/o error on routing socket No buffer space available - disabling kernel: [157516.495224] ntpd[2729]: segfault at 31 ip 0000000000000031 sp 00007ffff9f11788 error 14 in libpthread-2.15.so[7f967a5d9000+18000] OS: Ubuntu 12.04.4 LTS Kernel: 3.11.0-19-generic I tried to compare it to other servers, and the only thing I could find that is different is that while it's up (before it crashes) I can see the following when running "lsof | grep ntp": ntpd 2729 ntp 49u sock 0,7 0t0 2473952565 can't identify protocol. 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