fixup! [LibOS] Add support for timerfd system calls

Signed-off-by: Kailun Qin <[email protected]>

Author: kailun-qin

libos/src/sys/libos_timerfd.c

@@ -162,17 +162,17 @@ long libos_syscall_timerfd_settime(int fd, int flags, const struct __kernel_itim
     if (!hdl)
         return -EBADF;
 
+    if (hdl->type != TYPE_TIMERFD) {
+        ret = -EINVAL;
+        goto out;
+    }
+
     if (hdl->info.timerfd.broken_in_child) {
         log_warning("Child process tried to access timerfd created by parent process. This is "
                     "disallowed in Gramine.");
         return -EIO;
     }
 
-    if (hdl->type != TYPE_TIMERFD) {
-        ret = -EINVAL;
-        goto out;
-    }
-
     if (!is_user_memory_readable(value, sizeof(*value))) {
         ret = -EFAULT;
         goto out;
@@ -253,17 +253,17 @@ long libos_syscall_timerfd_gettime(int fd, struct __kernel_itimerspec* value) {
     if (!hdl)
         return -EBADF;
 
+    if (hdl->type != TYPE_TIMERFD) {
+        ret = -EINVAL;
+        goto out;
+    }
+
     if (hdl->info.timerfd.broken_in_child) {
         log_warning("Child process tried to access timerfd created by parent process. This is "
                     "disallowed in Gramine.");
         return -EIO;
     }
 
-    if (hdl->type != TYPE_TIMERFD) {
-        ret = -EINVAL;
-        goto out;
-    }
-
     if (!is_user_memory_writable(value, sizeof(*value))) {
         ret = -EFAULT;
         goto out;

libos/test/regression/timerfd.c

@@ -210,7 +210,7 @@ static void test_epoll_modes(int fd) {
         errx(1, "epoll: unexpected number of fds (expected 1, got %u)", nfds);
 
     /* waiting for another event without reading the expiration count: here, even though the timer
-     * expired at least one, there is no event reported because we're in edge-triggered mode (which
+     * expired at least once, there is no event reported because we're in edge-triggered mode (which
      * does not "reset" the event since there was no read) */
     nfds = CHECK(epoll_wait(epfd, events, 1, /*timeout=*/PERIODIC_INTERVAL * 1000 * 2));
     if (nfds != 0)