SCTP can start an association through sendmsg() or CONNECTX. These paths
call the SCTP-specific sctp_bind_connect hook instead of the normal socket
connect hook, but AppArmor does not register it. As a result, a profile can
deny connect and allow send or setopt, yet a task can still create an SCTP
association.
Register the SCTP hook. Ask for connect permission when SENDMSG_CONNECT
or CONNECTX creates an association.
Fixes: 56974a6fcfef ("apparmor: add base infastructure for socket mediation")
Assisted-by: LLM
Signed-off-by: Jérémy Jean <[email protected]>
---
security/apparmor/lsm.c | 14 ++++++++++++++
1 file changed, 14 insertions(+)
diff --git a/security/apparmor/lsm.c b/security/apparmor/lsm.c
index d502ad0ac26f..dba078c73abc 100644
--- a/security/apparmor/lsm.c
+++ b/security/apparmor/lsm.c
@@ -15,6 +15,7 @@
#include <linux/mount.h>
#include <linux/namei.h>
#include <linux/ptrace.h>
+#include <linux/sctp.h>
#include <linux/ctype.h>
#include <linux/sysctl.h>
#include <linux/sysfs.h>
@@ -1405,6 +1406,18 @@ static int apparmor_socket_connect(struct socket *sock,
return aa_sk_perm(OP_CONNECT, AA_MAY_CONNECT, sock->sk);
}
+static int apparmor_sctp_bind_connect(struct sock *sk, int optname,
+ struct sockaddr *address, int addrlen)
+{
+ switch (optname) {
+ case SCTP_SOCKOPT_CONNECTX:
+ case SCTP_SENDMSG_CONNECT:
+ return aa_sk_perm(OP_CONNECT, AA_MAY_CONNECT, sk);
+ }
+
+ return 0;
+}
+
static int apparmor_socket_listen(struct socket *sock, int backlog)
{
AA_BUG(!sock);
@@ -1823,6 +1836,7 @@ static struct security_hook_list apparmor_hooks[]
__ro_after_init = {
LSM_HOOK_INIT(socket_getsockopt, apparmor_socket_getsockopt),
LSM_HOOK_INIT(socket_setsockopt, apparmor_socket_setsockopt),
LSM_HOOK_INIT(socket_shutdown, apparmor_socket_shutdown),
+ LSM_HOOK_INIT(sctp_bind_connect, apparmor_sctp_bind_connect),
#ifdef CONFIG_NETWORK_SECMARK
LSM_HOOK_INIT(socket_sock_rcv_skb, apparmor_socket_sock_rcv_skb),
#endif
--
2.47.3
