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| author | Eric W. Biederman <ebiederm@xmission.com> | 2014-12-05 19:36:04 -0600 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2015-01-08 09:58:17 -0800 |
| commit | afb5285388ce7e7623ab9ddb08f287551e70426f (patch) | |
| tree | e6b27a20cf1f92f1b6bd6863fb11c66de2b3a525 /kernel | |
| parent | 1c587ee50ec44a2cf07cd160c214a683608b4d2c (diff) | |
| download | lwn-afb5285388ce7e7623ab9ddb08f287551e70426f.tar.gz lwn-afb5285388ce7e7623ab9ddb08f287551e70426f.zip | |
userns: Allow setting gid_maps without privilege when setgroups is disabled
commit 66d2f338ee4c449396b6f99f5e75cd18eb6df272 upstream.
Now that setgroups can be disabled and not reenabled, setting gid_map
without privielge can now be enabled when setgroups is disabled.
This restores most of the functionality that was lost when unprivileged
setting of gid_map was removed. Applications that use this functionality
will need to check to see if they use setgroups or init_groups, and if they
don't they can be fixed by simply disabling setgroups before writing to
gid_map.
Reviewed-by: Andy Lutomirski <luto@amacapital.net>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/user_namespace.c | 5 |
1 files changed, 5 insertions, 0 deletions
diff --git a/kernel/user_namespace.c b/kernel/user_namespace.c index 9da8cbbcd985..3f2fb33d291a 100644 --- a/kernel/user_namespace.c +++ b/kernel/user_namespace.c @@ -814,6 +814,11 @@ static bool new_idmap_permitted(const struct file *file, kuid_t uid = make_kuid(ns->parent, id); if (uid_eq(uid, cred->euid)) return true; + } else if (cap_setid == CAP_SETGID) { + kgid_t gid = make_kgid(ns->parent, id); + if (!(ns->flags & USERNS_SETGROUPS_ALLOWED) && + gid_eq(gid, cred->egid)) + return true; } } |