From: Daniel Jurgens <danielj@xxxxxxxxxxxx>
Add a generic notificaiton mechanism in the LSM. Interested consumers
can register a callback with the LSM and security modules can produce
events.
Because access to Infiniband QPs are enforced in the setup phase of a
connection security should be enforced again if the policy changes.
Register infiniband devices for policy change notification and check all
QPs on that device when the notification is received.
Add a call to the notification mechanism from SELinux when the AVC
cache changes or setenforce is cleared.
Signed-off-by: Daniel Jurgens <danielj@xxxxxxxxxxxx>
---
v2:
- new patch that has the generic notification, replaces selinux and
IB/core patches related to the ib_flush callback. Yuval Shaia and Paul
Moore
v3:
- use notifier chains. Paul Moore
v4:
- Seperate avc callback for LSM notifier. Paul Moore
v5:
- Fix link error when CONFIG_SECURITY is not set. Build Robot
drivers/infiniband/core/device.c | 53 ++++++++++++++++++++++++++++++++++++++++
include/linux/security.h | 23 +++++++++++++++++
security/security.c | 20 +++++++++++++++
security/selinux/hooks.c | 11 +++++++++
security/selinux/selinuxfs.c | 2 ++
5 files changed, 109 insertions(+)
diff --git a/drivers/infiniband/core/device.c b/drivers/infiniband/core/device.c
index 92e0b89..63ebaab 100644
--- a/drivers/infiniband/core/device.c
+++ b/drivers/infiniband/core/device.c
@@ -39,6 +39,8 @@
#include <linux/init.h>
#include <linux/mutex.h>
#include <linux/netdevice.h>
+#include <linux/security.h>
+#include <linux/notifier.h>
#include <rdma/rdma_netlink.h>
#include <rdma/ib_addr.h>
#include <rdma/ib_cache.h>
@@ -82,6 +84,14 @@ static LIST_HEAD(client_list);
static DEFINE_MUTEX(device_mutex);
static DECLARE_RWSEM(lists_rwsem);
+static int ib_security_change(struct notifier_block *nb, unsigned long event,
+ void *lsm_data);
+static void ib_policy_change_task(struct work_struct *work);
+static DECLARE_WORK(ib_policy_change_work, ib_policy_change_task);
+
+static struct notifier_block ibdev_lsm_nb = {
+ .notifier_call = ib_security_change,
+};
static int ib_device_check_mandatory(struct ib_device *device)
{
@@ -341,6 +351,40 @@ static int setup_port_pkey_list(struct ib_device *device)
return 0;
}
+static void ib_policy_change_task(struct work_struct *work)
+{
+ struct ib_device *dev;
+
+ down_read(&lists_rwsem);
+ list_for_each_entry(dev, &device_list, core_list) {
+ int i;
+
+ for (i = rdma_start_port(dev); i <= rdma_end_port(dev); i++) {
+ u64 sp;
+ int ret = ib_get_cached_subnet_prefix(dev,
+ i,
+ &sp);
+
+ WARN_ONCE(ret,
+ "ib_get_cached_subnet_prefix err: %d, this should never happen here\n",
+ ret);
+ ib_security_cache_change(dev, i, sp);
+ }
+ }
+ up_read(&lists_rwsem);
+}
+
+static int ib_security_change(struct notifier_block *nb, unsigned long event,
+ void *lsm_data)
+{
+ if (event != LSM_POLICY_CHANGE)
+ return NOTIFY_DONE;
+
+ schedule_work(&ib_policy_change_work);
+
+ return NOTIFY_OK;
+}
+
/**
* ib_register_device - Register an IB device with IB core
* @device:Device to register
@@ -1104,10 +1148,18 @@ static int __init ib_core_init(void)
goto err_sa;
}
+ ret = register_lsm_notifier(&ibdev_lsm_nb);
+ if (ret) {
+ pr_warn("Couldn't register LSM notifier. ret %d\n", ret);
+ goto err_ibnl_clients;
+ }
+
ib_cache_setup();
return 0;
+err_ibnl_clients:
+ ib_remove_ibnl_clients();
err_sa:
ib_sa_cleanup();
err_mad:
@@ -1127,6 +1179,7 @@ static int __init ib_core_init(void)
static void __exit ib_core_cleanup(void)
{
+ unregister_lsm_notifier(&ibdev_lsm_nb);
ib_cache_cleanup();
ib_remove_ibnl_clients();
ib_sa_cleanup();
diff --git a/include/linux/security.h b/include/linux/security.h
index 8c73ee0..f96e333 100644
--- a/include/linux/security.h
+++ b/include/linux/security.h
@@ -69,6 +69,10 @@ struct audit_krule;
struct user_namespace;
struct timezone;
+enum lsm_event {
+ LSM_POLICY_CHANGE,
+};
+
/* These functions are in security/commoncap.c */
extern int cap_capable(const struct cred *cred, struct user_namespace *ns,
int cap, int audit);
@@ -164,6 +168,10 @@ struct security_mnt_opts {
int num_mnt_opts;
};
+int call_lsm_notifier(enum lsm_event event, void *data);
+int register_lsm_notifier(struct notifier_block *nb);
+int unregister_lsm_notifier(struct notifier_block *nb);
+
static inline void security_init_mnt_opts(struct security_mnt_opts *opts)
{
opts->mnt_opts = NULL;
@@ -382,6 +390,21 @@ int security_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen);
struct security_mnt_opts {
};
+static inline int call_lsm_notifier(enum lsm_event event, void *data)
+{
+ return 0;
+}
+
+static inline int register_lsm_notifier(struct notifier_block *nb)
+{
+ return 0;
+}
+
+static inline int unregister_lsm_notifier(struct notifier_block *nb)
+{
+ return 0;
+}
+
static inline void security_init_mnt_opts(struct security_mnt_opts *opts)
{
}
diff --git a/security/security.c b/security/security.c
index a142a0b..6eef315 100644
--- a/security/security.c
+++ b/security/security.c
@@ -35,6 +35,8 @@
#define SECURITY_NAME_MAX 10
struct security_hook_heads security_hook_heads __lsm_ro_after_init;
+static ATOMIC_NOTIFIER_HEAD(lsm_notifier_chain);
+
char *lsm_names;
/* Boot-time LSM user choice */
static __initdata char chosen_lsm[SECURITY_NAME_MAX + 1] =
@@ -162,6 +164,24 @@ void __init security_add_hooks(struct security_hook_list *hooks, int count,
panic("%s - Cannot get early memory.\n", __func__);
}
+int call_lsm_notifier(enum lsm_event event, void *data)
+{
+ return atomic_notifier_call_chain(&lsm_notifier_chain, event, data);
+}
+EXPORT_SYMBOL(call_lsm_notifier);
+
+int register_lsm_notifier(struct notifier_block *nb)
+{
+ return atomic_notifier_chain_register(&lsm_notifier_chain, nb);
+}
+EXPORT_SYMBOL(register_lsm_notifier);
+
+int unregister_lsm_notifier(struct notifier_block *nb)
+{
+ return atomic_notifier_chain_unregister(&lsm_notifier_chain, nb);
+}
+EXPORT_SYMBOL(unregister_lsm_notifier);
+
/*
* Hook list operation macros.
*
diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c
index e298000..bc77c56 100644
--- a/security/selinux/hooks.c
+++ b/security/selinux/hooks.c
@@ -171,6 +171,14 @@ static int selinux_netcache_avc_callback(u32 event)
return 0;
}
+static int selinux_lsm_notifier_avc_callback(u32 event)
+{
+ if (event == AVC_CALLBACK_RESET)
+ call_lsm_notifier(LSM_POLICY_CHANGE, NULL);
+
+ return 0;
+}
+
/*
* initialise the security for the init task
*/
@@ -6399,6 +6407,9 @@ static __init int selinux_init(void)
if (avc_add_callback(selinux_netcache_avc_callback, AVC_CALLBACK_RESET))
panic("SELinux: Unable to register AVC netcache callback\n");
+ if (avc_add_callback(selinux_lsm_notifier_avc_callback, AVC_CALLBACK_RESET))
+ panic("SELinux: Unable to register AVC LSM notifier callback\n");
+
if (selinux_enforcing)
printk(KERN_DEBUG "SELinux: Starting in enforcing mode\n");
else
diff --git a/security/selinux/selinuxfs.c b/security/selinux/selinuxfs.c
index ce71718..c8467dd 100644
--- a/security/selinux/selinuxfs.c
+++ b/security/selinux/selinuxfs.c
@@ -163,6 +163,8 @@ static ssize_t sel_write_enforce(struct file *file, const char __user *buf,
avc_ss_reset(0);
selnl_notify_setenforce(selinux_enforcing);
selinux_status_update_setenforce(selinux_enforcing);
+ if (!selinux_enforcing)
+ call_lsm_notifier(LSM_POLICY_CHANGE, NULL);
}
length = count;
out:
--
2.7.4
