Temporary directory name conflicts when runnig inside containers with shared /tmp

[eugenesan]

When running inside Distrobox container temporary directory name conflicts with mc instance running on the host machine which has different permissions:

root@ubuntu:~# mc
Directory /tmp/mc-root is not owned by you
Temporary files will be created in /tmp
Press any key to continue...

Trivial fix I came up with is to add process ID to the directory name.
Also, that might be useful when running multiple instances on the host.

Please find the fix attached to the tocket

[eugenesan]

Add process ID to the temporary directory name

[andrew_b]

Branch: 4535_tmpdir_name
changeset:2fda4c66707341dcf8e8013710cc202c1507be72

[zaytsev]

Hi Andrew, I'm not sure what was the original reasoning behind making the directories per-user, but now that you're going into the direction of making them unique (per process), isn't it much better to use the POSIX mkdtemp API (or rather get_tmp_dir from glib) and remove all our strange black magic altogether? There was already CVE-2004-0231 in the past due to homegrown adventurous handling of temporary directories...

[andrew_b]

Replying to zaytsev:

isn't it much better to use the POSIX mkdtemp API

Probably yes.

(or rather get_tmp_dir from glib)

g_get_tmp_dir uses $TMPDIR. mc tries to use $MC_TMPDIR if it's set and $TMPDIR otherwise.

[zaytsev]

g_get_tmp_dir uses $TMPDIR. mc tries to use $MC_TMPDIR if it's set and $TMPDIR otherwise.

Well, there seems to be another more flexible API: g_dir_make_tmp - maybe you could use that instead.

[andrew_b]

Replying to zaytsev:

g_get_tmp_dir uses $TMPDIR. mc tries to use $MC_TMPDIR if it's set and $TMPDIR otherwise.

Well, there seems to be another more flexible API: g_dir_make_tmp - maybe you could use that instead.

It doesn't help us: g_dir_make_tmp calls g_get_tmp_dir.
I think we should keep the $MC_TMPDIR usage, so we have to write a code for temporary directory name. Something like

    g_snprintf (buffer, sizeof (buffer), "%s/mc-XXXXXX", sys_tmp);
    tmpdir = g_mkdtemp (buffer);
    if (tmpdir != NULL)
        g_setenv ("MC_TMPDIR", tmpdir, TRUE);

[zaytsev]

You are right, I agree!

[andrew_b]

comment:1 updated.

[andrew_b]

Merged to master: [794823b885b63439ab8c2ce5bc4436855c603834].

[andrew_b]

A typo in the commit message: s/drirectory/directory/ :-(