This snippet from wiki's page on "ccache" unnecessarily suggests to excessively open the permissions on /var/cache/ccache to umask=0002: > FEATURES="ccache" > > # Portage defaults to ${PORTAGE_TMPDIR}/ccache unless CCACHE_DIR is > # set in make.conf or in /etc/portage/env (or similar). > #CCACHE_DIR="/var/cache/ccache" > # If using a directory that Portage doesn't control, e.g. /var/cache/ccache, > # this may be needed in some cases, but has some security implications. > # See bug 492910. > #CCACHE_UMASK="0002" Even though the bug which it links (492910) has a comment () that suggests a better fix without the umask=0002 vulnerability: > chown -R portage:portage . > chmod g+s . Not to mention that portage's "prepare_build_dirs.py" seem to already handle this by setting the permissions for directories specified in CCACHE_DIR. I suggest to update the code snippet to: > FEATURES="ccache" > > # Unless CCACHE_DIR is set explicitly, portage overrides it to portage's tmp > # directory ${PORTAGE_TMPDIR}/ccache, which is possibly subject to deletion > # after reboots (rendering ccache less effective), and causes "ccache" to ignore > # "cache_dir=..." in /etc/ccache.conf. Therefore, to set ccache's directory to > # a non-temporary path, CCACHE_DIR has to be set, e.g.: > > CCACHE_DIR="/var/cache/ccache" > > # If portage doesn't set the permissions of "/var/cache/ccache" correctly > # (bug 492910), then set their permissions manually, e.g: > # chown -R portage:portage /var/cache/ccache > # chmod g+s /var/cache/ccache > # or set the following option in make.conf (warning: creates a vulnerability): > # CCACHE_UMASK="0002" Note: I can't add URLs as my account is new. Replace "bug 492910" with the actual bug's URL.
(In reply to otzma.vindicus from comment #0) > This snippet from wiki's page on "ccache" unnecessarily suggests to > excessively open the permissions on /var/cache/ccache to umask=0002: > It does not "suggest" to, it mentions that someone may need to and includes a link to the bug for context. > > FEATURES="ccache" > > > > # Portage defaults to ${PORTAGE_TMPDIR}/ccache unless CCACHE_DIR is > > # set in make.conf or in /etc/portage/env (or similar). > > #CCACHE_DIR="/var/cache/ccache" > > # If using a directory that Portage doesn't control, e.g. /var/cache/ccache, > > # this may be needed in some cases, but has some security implications. > > # See bug 492910. > > #CCACHE_UMASK="0002" > > Even though the bug which it links (492910) has a comment () that suggests a > better fix without the umask=0002 vulnerability: > That has the same issue anyway if /var/cache/ccache is shared with other users, though. > I suggest to update the code snippet to: > The wiki is free for anyone to edit. You can edit it yourself on the wiki or suggest changes via the talk page.
