Fix reading /etc/machine-id in kernel-install #25388
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The kernel-install script has code to read the contents of /etc/machine-id into the MACHINE_ID variable. Depending on the variable content kernel-install either logs the value or creates a new machine id via 'systemd-id128 new'. In that logic there is one issue. If the file /etc/machine-id exists but is empty, the script tries to call read on an empty file which return with an exit code != 0. As the script code also uses 'set -e', kernel-install will exit at this point which is unexpected. The condition of an empty /etc/machine-id file exists for example when building OS images, which should initialize the system id on first boot but not staticly inside of the image. afaik an empty /etc/machine-id is also a common approach to make systemd indicate that it should create a new system id. Because of this, the commit makes sure the reading of /etc/machine-id does not fail in any case such that the handling of the MACHINE_ID variable takes place.
Conan-Kudo
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bluca
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Per review comment use test -s to make sure the subsequent reading of /etc/machine-id is only done if the file exists and has size > 0
bluca
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yuwata
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Conan-Kudo
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Nov 15, 2022
|
btw, to be fully correct we should add code that handles the case where /etc/machine-id contains the string "uninitialized", too. As per man page machine-id(5). |
yes good point. I opened #25407 with a first suggestion how to handle it. Thanks |
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eworm-de
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Nov 28, 2022
* Fix reading /etc/machine-id in kernel-install The kernel-install script has code to read the contents of /etc/machine-id into the MACHINE_ID variable. Depending on the variable content kernel-install either logs the value or creates a new machine id via 'systemd-id128 new'. In that logic there is one issue. If the file /etc/machine-id exists but is empty, the script tries to call read on an empty file which return with an exit code != 0. As the script code also uses 'set -e', kernel-install will exit at this point which is unexpected. The condition of an empty /etc/machine-id file exists for example when building OS images, which should initialize the system id on first boot but not staticly inside of the image. afaik an empty /etc/machine-id is also a common approach to make systemd indicate that it should create a new system id. Because of this, the commit makes sure the reading of /etc/machine-id does not fail in any case such that the handling of the MACHINE_ID variable takes place. (cherry picked from commit 883e7cb)
d-hatayama
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Feb 15, 2023
* Fix reading /etc/machine-id in kernel-install The kernel-install script has code to read the contents of /etc/machine-id into the MACHINE_ID variable. Depending on the variable content kernel-install either logs the value or creates a new machine id via 'systemd-id128 new'. In that logic there is one issue. If the file /etc/machine-id exists but is empty, the script tries to call read on an empty file which return with an exit code != 0. As the script code also uses 'set -e', kernel-install will exit at this point which is unexpected. The condition of an empty /etc/machine-id file exists for example when building OS images, which should initialize the system id on first boot but not staticly inside of the image. afaik an empty /etc/machine-id is also a common approach to make systemd indicate that it should create a new system id. Because of this, the commit makes sure the reading of /etc/machine-id does not fail in any case such that the handling of the MACHINE_ID variable takes place.
valentindavid
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Aug 8, 2023
The kernel-install script has code to read the contents of /etc/machine-id into the MACHINE_ID variable. Depending on the variable content kernel-install either logs the value or creates a new machine id via 'systemd-id128 new'. In that logic there is one issue. If the file /etc/machine-id exists but is empty, the script tries to call read on an empty file which return with an exit code != 0. As the script code also uses 'set -e', kernel-install will exit at this point which is unexpected. The condition of an empty /etc/machine-id file exists for example when building OS images, which should initialize the system id on first boot but not staticly inside of the image. afaik an empty /etc/machine-id is also a common approach to make systemd indicate that it should create a new system id. Because of this, the commit makes sure the reading of /etc/machine-id does not fail in any case such that the handling of the MACHINE_ID variable takes place. (cherry picked from commit 883e7cb) (cherry picked from commit d34ea41) Backported for https://bugzilla.redhat.com/show_bug.cgi?id=2148464.
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The kernel-install script has code to read the contents of
/etc/machine-idinto theMACHINE_IDvariable. Depending on the variable content kernel-install either logs the value or creates a new machine id viasystemd-id128 new. In that logic there is one issue. If the file/etc/machine-idexists but is empty, the script tries to call read on an empty file which return with an exit code != 0. As the script code also usesset -e, kernel-install will exit at this point which is unexpected.The condition of an empty /etc/machine-id file exists for example when building OS images, which should initialize the system id on first boot but not staticly inside of the image. afaik an empty
/etc/machine-idis also a common approach to make systemd indicate that it should create a new system id. Because of this, the commit makes sure the reading of/etc/machine-iddoes not fail in any case such that the handling of the MACHINE_ID variable takes place.