casync bundle creation fails with "unable to find mounted device for bundle" when building inside container #679
Description
Since RAUC version 1.5 creating casync bundles no longer works. This is the relevant output when the bundle.bbclass executes the convert command to create the casync bundle:
rauc-Message: 13:21:55.950: Debug log domains: 'rauc'
(rauc:34224): rauc-DEBUG: 13:21:55.951: convert start
(rauc:34224): rauc-DEBUG: 13:21:55.951: system config not found, using default values
rauc-Message: 13:21:55.951: Failed to resolve realpath for '/dev/disk/by-uuid/be5faaeb-1680-4ca2-af65-f30f06dab903'
(rauc:34224): rauc-DEBUG: 13:21:55.951: input bundle: /home/user/documents/yocto/imx6ul/dunfell/build/tmp/work/machine/headless-bundle/1.0-r0/build/bundle.raucb
(rauc:34224): rauc-DEBUG: 13:21:55.951: output bundle: /home/user/documents/yocto/imx6ul/dunfell/build/tmp/work/machine/headless-bundle/1.0-r0/build/casync-bundle.raucb
rauc-Message: 13:21:55.951: Reading bundle: /home/user/documents/yocto/imx6ul/dunfell/build/tmp/work/machine/headless-bundle/1.0-r0/build/bundle.raucb
rauc-Message: 13:21:55.952: Verifying bundle signature...
(rauc:34224): rauc-DEBUG: 13:21:55.952: initial check_bundle_access failed with: unable to find mounted device for bundle
unable to find mounted device for bundle
WARNING: exit code 1 from a shell command.
I am looking at the code changes that version 1.5 brings but I do not really understand yet what the exact issue is with this one. AFAIK check_bundle_access() checks several parameters to prevent unintended write access to the bundle. Though I am unsure which device the error message is referring to and what is wrong with it.