** Description changed:
+ [Impact]
+
+ * In NTP 4.2.8p4 there are several races that can cause a crash on
+ startup or on a bit later but still on startup by DNS querying a
+ peer.
+
+ * The crash obviously affects users, especially as it seems - due to
+ its racy nature - not appear on most, but severely hamstring some
+ other users.
+
+ * The details are a bit blurred, but overall there were four fixes
+ upstream that address just this "kind of issue" that seemed to
+ surface post 4.2.8p4.
+
+ [Test Case]
+
+ * Start NTP (service)
+
+ * Expectation: work
+
+ * Failure: Crash
+
+ * Constraints: this is a race, it seems to appear at <0.1% chance to
+ all systems I have (or lower - as I just can say it didn't trigger in
+ 1000 tests). But that matches other reports. OTOH for some systems it
+ seems to trigger >50% which also matches the high amount of crash
+ reports (close to 20k now) as referred in comment 43
+
+ [Regression Potential]
+
+ * Eventually the change is rather invasive as it changes the locking
+ scheme of parts of the code - so there surely is some regression
+ potential.
+
+ * Fortunately not all, but most of this change is upstream and tested
+ quite heavily a few months already.
+
+ * I tested as good as I could and could neither in code nor in test
+ find an obvious weakness, and looking at all the crash reports it is
+ about time.
+
+ [Other Info]
+
+ * While all study of bugs, upstream changes and tests suggest we
+ haven't broken anything, still I have to admit that "on my own" I
+ can't confirm that it fixed the bug. So we are really dependent on
+ the reporters here that seem to have the kind of hardware where it
+ "crashes reliably".
+
+
+ --------
+
+
ntp crashes every time the network goes up or down while the system is
running and also crashes after booting up without network.
- ---
+ ---
ApportVersion: 2.20.1-0ubuntu1
Architecture: amd64
CurrentDesktop: XFCE
DistroRelease: Ubuntu 16.04
InstallationDate: Installed on 2016-03-12 (26 days ago)
InstallationMedia: Xubuntu 16.04 LTS "Xenial Xerus" - Alpha amd64 (20160224)
NtpStatus: ntpq: read: Connection refused
Package: ntp 1:4.2.8p4+dfsg-3ubuntu4
PackageArchitecture: amd64
ProcCmdline: BOOT_IMAGE=/boot/vmlinuz-4.4.0-17-generic
root=UUID=306314bc-efcb-4c2d-b0e9-e05ec92ed0f0 ro
ProcVersionSignature: Ubuntu 4.4.0-17.33-generic 4.4.6
Tags: xenial
Uname: Linux 4.4.0-17-generic x86_64
UpgradeStatus: No upgrade log present (probably fresh install)
UserGroups: adm cdrom dip lpadmin plugdev sambashare sudo
_MarkForUpload: True
- ---
+ ---
ApportVersion: 2.20.1-0ubuntu1
Architecture: amd64
CurrentDesktop: XFCE
DistroRelease: Ubuntu 16.04
InstallationDate: Installed on 2016-03-12 (31 days ago)
InstallationMedia: Xubuntu 16.04 LTS "Xenial Xerus" - Alpha amd64 (20160224)
NtpStatus: ntpq: read: Connection refused
Package: ntp 1:4.2.8p4+dfsg-3ubuntu5
PackageArchitecture: amd64
ProcCmdline: BOOT_IMAGE=/boot/vmlinuz-4.4.0-18-generic
root=UUID=306314bc-efcb-4c2d-b0e9-e05ec92ed0f0 ro
ProcVersionSignature: Ubuntu 4.4.0-18.34-generic 4.4.6
Tags: xenial
Uname: Linux 4.4.0-18-generic x86_64
UpgradeStatus: No upgrade log present (probably fresh install)
UserGroups: adm cdrom dip lpadmin plugdev sambashare sudo
_MarkForUpload: True
- ---
+ ---
ApportVersion: 2.20.1-0ubuntu1
Architecture: amd64
CurrentDesktop: XFCE
DistroRelease: Ubuntu 16.04
InstallationDate: Installed on 2016-04-13 (0 days ago)
InstallationMedia: Xubuntu 16.04 LTS "Xenial Xerus" - Beta amd64 (20160412)
NtpStatus: ntpq: read: Connection refused
Package: ntp 1:4.2.8p4+dfsg-3ubuntu5
PackageArchitecture: amd64
ProcCmdline: BOOT_IMAGE=/boot/vmlinuz-4.4.0-18-generic
root=UUID=13f57794-2e19-4a56-836a-94185bba5ec5 ro quiet splash
ProcVersionSignature: Ubuntu 4.4.0-18.34-generic 4.4.6
Tags: xenial
Uname: Linux 4.4.0-18-generic x86_64
UpgradeStatus: No upgrade log present (probably fresh install)
UserGroups: adm cdrom dip lpadmin plugdev sambashare sudo
_MarkForUpload: True
- ---
+ ---
ApportVersion: 2.20.1-0ubuntu1
Architecture: amd64
CurrentDesktop: XFCE
DistroRelease: Ubuntu 16.04
InstallationDate: Installed on 2016-04-13 (0 days ago)
InstallationMedia: Xubuntu 16.04 LTS "Xenial Xerus" - Beta amd64 (20160412)
NtpStatus: ntpq: read: Connection refused
Package: ntp 1:4.2.8p4+dfsg-3ubuntu5
PackageArchitecture: amd64
ProcCmdline: BOOT_IMAGE=/boot/vmlinuz-4.4.0-18-generic
root=UUID=13f57794-2e19-4a56-836a-94185bba5ec5 ro quiet splash
ProcVersionSignature: Ubuntu 4.4.0-18.34-generic 4.4.6
Tags: xenial
Uname: Linux 4.4.0-18-generic x86_64
UpgradeStatus: No upgrade log present (probably fresh install)
UserGroups: adm cdrom dip lpadmin plugdev sambashare sudo
_MarkForUpload: True
- ---
+ ---
ApportVersion: 2.20.1-0ubuntu2
Architecture: amd64
CurrentDesktop: XFCE
DistroRelease: Ubuntu 16.04
InstallationDate: Installed on 2016-04-14 (3 days ago)
InstallationMedia: Xubuntu 16.04 LTS "Xenial Xerus" - Beta amd64 (20160412)
NtpStatus: ntpq: read: Connection refused
Package: ntp 1:4.2.8p4+dfsg-3ubuntu5
PackageArchitecture: amd64
ProcCmdline: BOOT_IMAGE=/boot/vmlinuz-4.4.0-20-generic
root=UUID=b9c0528f-e81f-4b08-9b31-032f14f72ccd ro quiet splash vt.handoff=7
ProcVersionSignature: Ubuntu 4.4.0-20.36-generic 4.4.6
Tags: xenial
Uname: Linux 4.4.0-20-generic x86_64
UpgradeStatus: No upgrade log present (probably fresh install)
UserGroups: adm cdrom dip lpadmin plugdev sambashare sudo
_MarkForUpload: True
- ---
+ ---
ApportVersion: 2.20.1-0ubuntu2
Architecture: amd64
CurrentDesktop: XFCE
DistroRelease: Ubuntu 16.04
InstallationDate: Installed on 2016-04-14 (3 days ago)
InstallationMedia: Xubuntu 16.04 LTS "Xenial Xerus" - Beta amd64 (20160412)
NtpStatus: ntpq: read: Connection refused
Package: ntp 1:4.2.8p4+dfsg-3ubuntu5
PackageArchitecture: amd64
ProcCmdline: BOOT_IMAGE=/boot/vmlinuz-4.4.0-20-generic
root=UUID=b9c0528f-e81f-4b08-9b31-032f14f72ccd ro quiet splash vt.handoff=7
ProcVersionSignature: Ubuntu 4.4.0-20.36-generic 4.4.6
Tags: xenial
Uname: Linux 4.4.0-20-generic x86_64
UpgradeStatus: No upgrade log present (probably fresh install)
UserGroups: adm cdrom dip lpadmin plugdev sambashare sudo
_MarkForUpload: True
- ---
+ ---
ApportVersion: 2.20.1-0ubuntu2.1
Architecture: amd64
CurrentDesktop: XFCE
DistroRelease: Ubuntu 16.04
InstallationDate: Installed on 2016-04-14 (63 days ago)
InstallationMedia: Xubuntu 16.04 LTS "Xenial Xerus" - Beta amd64 (20160412)
NtpStatus: ntpq: read: Connection refused
Package: ntp 1:4.2.8p4+dfsg-3ubuntu5
PackageArchitecture: amd64
ProcCmdline: BOOT_IMAGE=/boot/vmlinuz-4.4.0-25-generic
root=UUID=3aea4570-4011-4247-9636-68317385324d ro
ProcVersionSignature: Ubuntu 4.4.0-25.44-generic 4.4.13
Tags: xenial third-party-packages
Uname: Linux 4.4.0-25-generic x86_64
UpgradeStatus: No upgrade log present (probably fresh install)
UserGroups: adm cdrom dialout dip lpadmin mail netdev plugdev sambashare sudo
_MarkForUpload: True
** Changed in: ntp (Ubuntu Xenial)
Status: Confirmed => Fix Committed
** Patch added: "debdiff for Xenial SRU - v1"
https://bugs.launchpad.net/ubuntu/+source/ntp/+bug/1567540/+attachment/4711503/+files/SRU-fix-ntp-1567540.debdiff
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https://bugs.launchpad.net/bugs/1567540
Title:
ntpd crashed with SIGABRT (was: ntp crashes everytime the network goes
up or down.)
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