apparmor: root view labels should not be under user control
The root view of the label parse should not be exposed to user
control.
Signed-off-by: John Johansen <john.johansen@canonical.com>
Acked-by: Seth Arnold <seth.arnold@canonical.com>
diff --git a/security/apparmor/label.c b/security/apparmor/label.c
index 4721338..69c7451 100644
--- a/security/apparmor/label.c
+++ b/security/apparmor/label.c
@@ -1871,8 +1871,9 @@ struct aa_label *aa_label_strn_parse(struct aa_label *base, const char *str,
AA_BUG(!str);
str = skipn_spaces(str, n);
- if (str == NULL)
+ if (str == NULL || (*str == '=' && base != &root_ns->unconfined->label))
return ERR_PTR(-EINVAL);
+
len = label_count_strn_entries(str, end - str);
if (*str == '&' || force_stack) {
/* stack on top of base */
@@ -1881,8 +1882,6 @@ struct aa_label *aa_label_strn_parse(struct aa_label *base, const char *str,
if (*str == '&')
str++;
}
- if (*str == '=')
- base = &root_ns->unconfined->label;
error = vec_setup(profile, vec, len, gfp);
if (error)