fix: 内源代码检视问题

【背景】内源代码检视问题

【修改方案】
1，按检视意见，进行资源泄露等问题的修改

【影响】
对现有的产品编译不会有影响。

re #I4WV56
Signed-off-by: Nwangchen <wangchen64@huawei.com>

fs/vfs/epoll/fs_epoll.c

@@ -242,6 +242,11 @@ int epoll_ctl(int epfd, int op, int fd, struct epoll_event *ev)
         return ret;
     }
 
+    if (ev == NULL) {
+        set_errno(EINVAL);
+        return -1;
+    }
+
     switch (op) {
         case EPOLL_CTL_ADD:
             ret = CheckFdExist(epHead, fd);
@@ -304,7 +309,7 @@ int epoll_wait(int epfd, FAR struct epoll_event *evs, int maxevents, int timeout
         return -1;
     }
 
-    if (maxevents <= 0) {
+    if ((maxevents <= 0) || (evs == NULL)) {
         set_errno(EINVAL);
         return -1;
     }

syscall/fs_syscall.c

@@ -2570,7 +2570,9 @@ int SysPselect6(int nfds, fd_set *readfds, fd_set *writefds, fd_set *exceptfds,
     CPY_FROM_USER(exceptfds);
     DUP_FROM_USER(timeout, sizeof(struct timeval));
 
-    ((struct timeval *)timeout)->tv_usec = timeout->tv_nsec / 1000; /* 1000, convert ns to us */
+    if (timeout != NULL) {
+        ((struct timeval *)timeout)->tv_usec = timeout->tv_nsec / 1000; /* 1000, convert ns to us */
+    }
 
     if (data != NULL) {
         retVal = LOS_ArchCopyFromUser(&(setl.sig[0]), (int *)((UINTPTR)data[0]), sizeof(sigset_t));