net: Use ns_capable_noaudit() when determining net sysctl permissions The capability check should not be audited since it is only being used to determine the inode permissions. A failed check does not indicate a violation of security policy but, when an LSM is enabled, a denial audit message was being generated. The denial audit message caused confusion for some application authors because root-running Go applications always triggered the denial. To prevent this confusion, the capability check in net_ctl_permissions() is switched to the noaudit variant. BugLink: https://launchpad.net/bugs/1465724 Signed-off-by: Tyler Hicks <tyhicks@canonical.com> Acked-by: Serge E. Hallyn <serge.hallyn@ubuntu.com> Signed-off-by: James Morris <james.l.morris@oracle.com> [dtor: reapplied after e79c6a4fc923 ("net: make net namespace sysctls belong to container's owner") accidentally reverted the change.] Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/sysctl_net.c b/net/sysctl_net.c index 5bc1a3d..e0c71bd 100644 --- a/net/sysctl_net.c +++ b/net/sysctl_net.c
@@ -44,7 +44,7 @@ struct net *net = container_of(head->set, struct net, sysctls); /* Allow network administrator to have same access as root. */ - if (ns_capable(net->user_ns, CAP_NET_ADMIN)) { + if (ns_capable_noaudit(net->user_ns, CAP_NET_ADMIN)) { int mode = (table->mode >> 6) & 7; return (mode << 6) | (mode << 3) | mode; }