Comment 0 for bug 1218674

Hi,

Installing Click packages from appstore (click scope) in Ubuntu Touch images is unreliable.

I couldn't figure exactly which conditions trigger this, but "pkcon install-local some.click" works, and then installation from the scope works, however if I install straight from the scope it doens't work.

I've straced packagekit doing this and spotted some click traceback being written to a .crash which ends with:
Traceback:
 Traceback (most recent call last):
   File "/usr/bin/click", line 84, in <module>
     sys.exit(main())
   File "/usr/bin/click", line 79, in main
     mod.run(args)
   File "/usr/lib/python3/dist-packages/click/commands/install.py", line 41, in run
     installer.install(package_path, user=options.user)
   File "/usr/lib/python3/dist-packages/click/install.py", line 264, in install
     env=env, **kwargs)
   File "/usr/lib/python3.3/subprocess.py", line 544, in check_call
     raise CalledProcessError(retcode, cmd)
 subprocess.CalledProcessError: Command '['dpkg', '--force-not-root', '--instdir', '/opt/click.ubuntu.com/ar.com.beuno.hello-world/0.6', '--admindir', '/opt/click.ubuntu.com/ar.com.beuno.hello-world/0.6/.click', '--path-exclude', '*/.click/*', '--log', '/opt/click.ubuntu.com/.click/log', '--no-triggers', '--install', '/home/phablet/.local/share/download_manager/{97d4efcf-34bc-4919-a9b4-a1006890128e}/ar.com.beuno.hello-world-0.6.click']' returned non-zero exit status 1

Which suggests dpkg failing; which I found in the strace started as follows:
4519 execve("/usr/bin/dpkg", ["dpkg", "--force-not-root", "--instdir", "/opt/click.ubuntu.com/ar.com.beu"..., "--admindir", "/opt/click.ubuntu.com/ar.com.beu"..., "--path-exclude", "*/.click/*", "--log", "/opt/click.ubuntu.com/.click/log", "--no-triggers", "--install", "/home/phablet/.local/share/downl"...], [/* 7 vars */] <unfinished ...>

then running dpkg-split:
4520 execve("/usr/bin/dpkg-split", ["dpkg-split", "-Qao", "/opt/click.ubuntu.com/ar.com.beu"..., "/home/phablet/.local/share/downl"...], [/* 8 vars */]) = 0

but failing to open the package:
4520 open("/home/phablet/.local/share/download_manager/{8ec430e5-a192-493a-bdb6-478fffcb7ab1}/ar.com.beuno.hello-world-0.6.click", O_RDONLY|O_LARGEFILE) = -1 EACCES (Permission denied)
4520 write(2, "dpkg-split: error: unable to rea"..., 183) = 183

Immediately before, one can see:
4520 geteuid32() = 106

which was set when launching dpkg:
4519 setresgid32(107, 107, 107) = 0
4519 setresuid32(106, 106, 106) = 0
4519 getresuid32([106], [106], [106]) = 0
4519 getresgid32([107], [107], [107]) = 0

Indeed, click install had switched to the clickpkg user:
clickpkg:x:106:107::/nonexistent:/bin/false

So the problem is that .clicks may only be read by phablet user or root, but not by clickpkg.

Cheers,