security: introducing security_request_module
Calling request_module() will trigger a userspace upcall which will load a
new module into the kernel. This can be a dangerous event if the process
able to trigger request_module() is able to control either the modprobe
binary or the module binary. This patch adds a new security hook to
request_module() which can be used by an LSM to control a processes ability
to call request_module().
Signed-off-by: Eric Paris <eparis@redhat.com>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Signed-off-by: James Morris <jmorris@namei.org>
diff --git a/security/capability.c b/security/capability.c
index ec05730..1b943f5 100644
--- a/security/capability.c
+++ b/security/capability.c
@@ -396,6 +396,11 @@
return 0;
}
+static int cap_kernel_module_request(void)
+{
+ return 0;
+}
+
static int cap_task_setuid(uid_t id0, uid_t id1, uid_t id2, int flags)
{
return 0;
@@ -945,6 +950,7 @@
set_to_cap_if_null(ops, cred_commit);
set_to_cap_if_null(ops, kernel_act_as);
set_to_cap_if_null(ops, kernel_create_files_as);
+ set_to_cap_if_null(ops, kernel_module_request);
set_to_cap_if_null(ops, task_setuid);
set_to_cap_if_null(ops, task_fix_setuid);
set_to_cap_if_null(ops, task_setgid);
diff --git a/security/security.c b/security/security.c
index 4501c5e..0e993f4 100644
--- a/security/security.c
+++ b/security/security.c
@@ -709,6 +709,11 @@
return security_ops->kernel_create_files_as(new, inode);
}
+int security_kernel_module_request(void)
+{
+ return security_ops->kernel_module_request();
+}
+
int security_task_setuid(uid_t id0, uid_t id1, uid_t id2, int flags)
{
return security_ops->task_setuid(id0, id1, id2, flags);