Message ID | 995b77557010b2f9aed0e10435f7b8536df7a5db.1521179281.git.rgb@redhat.com (mailing list archive) |
---|---|
State | New, archived |
Headers | show |
On Fri, Mar 16, 2018 at 5:00 AM, Richard Guy Briggs <rgb@redhat.com> wrote: > Check if a task has existing children or co-threads and refuse to set > the container ID if either are present. Failure to check this could > permit games where a child scratches its parent's back to work around > inheritance and double-setting policy. > > Signed-off-by: Richard Guy Briggs <rgb@redhat.com> > --- > kernel/auditsc.c | 4 ++++ > 1 file changed, 4 insertions(+) I would just include this in patch 1/2 as I can't think of world where we wouldn't this check. > diff --git a/kernel/auditsc.c b/kernel/auditsc.c > index 29c8482..a6b0a52 100644 > --- a/kernel/auditsc.c > +++ b/kernel/auditsc.c > @@ -2087,6 +2087,10 @@ static int audit_set_containerid_perm(struct task_struct *task, u64 containerid) > /* if we don't have caps, reject */ > if (!capable(CAP_AUDIT_CONTROL)) > return -EPERM; > + /* if task has children or is not single-threaded, deny */ > + if (!list_empty(&task->children) || > + !(thread_group_leader(task) && thread_group_empty(task))) > + return -EPERM; > /* if containerid is unset, allow */ > if (!audit_containerid_set(task)) > return 0; > -- > 1.8.3.1
diff --git a/kernel/auditsc.c b/kernel/auditsc.c index 29c8482..a6b0a52 100644 --- a/kernel/auditsc.c +++ b/kernel/auditsc.c @@ -2087,6 +2087,10 @@ static int audit_set_containerid_perm(struct task_struct *task, u64 containerid) /* if we don't have caps, reject */ if (!capable(CAP_AUDIT_CONTROL)) return -EPERM; + /* if task has children or is not single-threaded, deny */ + if (!list_empty(&task->children) || + !(thread_group_leader(task) && thread_group_empty(task))) + return -EPERM; /* if containerid is unset, allow */ if (!audit_containerid_set(task)) return 0;
Check if a task has existing children or co-threads and refuse to set the container ID if either are present. Failure to check this could permit games where a child scratches its parent's back to work around inheritance and double-setting policy. Signed-off-by: Richard Guy Briggs <rgb@redhat.com> --- kernel/auditsc.c | 4 ++++ 1 file changed, 4 insertions(+)