seccomp: Operation for checking if an action is available

[linux-block.git] / kernel / seccomp.c

diff --git a/kernel/seccomp.c b/kernel/seccomp.c
index 5f19f41e4e5057bb8f5c3bd714435fbd60d53b2c..7a6089f66feda9639e11b74f55423b87135e447e 100644 (file)
--- a/kernel/seccomp.c
+++ b/kernel/seccomp.c
@@ -808,6 +808,27 @@ static inline long seccomp_set_mode_filter(unsigned int flags,
 }
 #endif
 
+static long seccomp_get_action_avail(const char __user *uaction)
+{
+       u32 action;
+
+       if (copy_from_user(&action, uaction, sizeof(action)))
+               return -EFAULT;
+
+       switch (action) {
+       case SECCOMP_RET_KILL:
+       case SECCOMP_RET_TRAP:
+       case SECCOMP_RET_ERRNO:
+       case SECCOMP_RET_TRACE:
+       case SECCOMP_RET_ALLOW:
+               break;
+       default:
+               return -EOPNOTSUPP;
+       }
+
+       return 0;
+}
+
 /* Common entry point for both prctl and syscall. */
 static long do_seccomp(unsigned int op, unsigned int flags,
                       const char __user *uargs)
@@ -819,6 +840,11 @@ static long do_seccomp(unsigned int op, unsigned int flags,
                return seccomp_set_mode_strict();
        case SECCOMP_SET_MODE_FILTER:
                return seccomp_set_mode_filter(flags, uargs);
+       case SECCOMP_GET_ACTION_AVAIL:
+               if (flags != 0)
+                       return -EINVAL;
+
+               return seccomp_get_action_avail(uargs);
        default:
                return -EINVAL;
        }