diff --git a/components/lwip/port/esp32/vfs_lwip.c b/components/lwip/port/esp32/vfs_lwip.c
index 54d71912b..3610d2e17 100644
--- a/components/lwip/port/esp32/vfs_lwip.c
+++ b/components/lwip/port/esp32/vfs_lwip.c
@@ -40,9 +40,9 @@ static void lwip_stop_socket_select_isr(BaseType_t *woken)
     }
 }
 
-static int lwip_fcntl_r_wrapper(int fd, int cmd, va_list args)
+static int lwip_fcntl_r_wrapper(int fd, int cmd, int arg)
 {
-    return lwip_fcntl_r(fd, cmd, va_arg(args, int));
+    return lwip_fcntl_r(fd, cmd, arg);
 }
 
 static int lwip_ioctl_r_wrapper(int fd, int cmd, va_list args)
diff --git a/components/vfs/include/esp_vfs.h b/components/vfs/include/esp_vfs.h
index e383c4363..49387dc5f 100644
--- a/components/vfs/include/esp_vfs.h
+++ b/components/vfs/include/esp_vfs.h
@@ -163,8 +163,8 @@ typedef struct
         int (*rmdir)(const char* name);
     };
     union {
-        int (*fcntl_p)(void* ctx, int fd, int cmd, va_list args);
-        int (*fcntl)(int fd, int cmd, va_list args);
+        int (*fcntl_p)(void* ctx, int fd, int cmd, int arg);
+        int (*fcntl)(int fd, int cmd, int arg);
     };
     union {
         int (*ioctl_p)(void* ctx, int fd, int cmd, va_list args);
diff --git a/components/vfs/vfs.c b/components/vfs/vfs.c
index 45633cd03..61a8f7065 100644
--- a/components/vfs/vfs.c
+++ b/components/vfs/vfs.c
@@ -657,21 +657,27 @@ int rmdir(const char* name)
     return ret;
 }
 
-int fcntl(int fd, int cmd, ...)
+int _fcntl_r(struct _reent *r, int fd, int cmd, int arg)
 {
     const vfs_entry_t* vfs = get_vfs_for_fd(fd);
     const int local_fd = get_local_fd(vfs, fd);
-    struct _reent* r = __getreent();
     if (vfs == NULL || local_fd < 0) {
         __errno_r(r) = EBADF;
         return -1;
     }
     int ret;
+    CHECK_AND_CALL(ret, r, vfs, fcntl, local_fd, cmd, arg);
+    return ret;
+}
+
+int __attribute__((weak)) fcntl(int fd, int cmd, ...)
+{
     va_list args;
     va_start(args, cmd);
-    CHECK_AND_CALL(ret, r, vfs, fcntl, local_fd, cmd, args);
+    int arg = va_arg(args, int);
     va_end(args);
-    return ret;
+    struct _reent* r = __getreent();
+    return _fcntl_r(r, fd, cmd, arg);
 }
 
 int ioctl(int fd, int cmd, ...)
diff --git a/components/vfs/vfs_uart.c b/components/vfs/vfs_uart.c
index ebff91a87..62308e424 100644
--- a/components/vfs/vfs_uart.c
+++ b/components/vfs/vfs_uart.c
@@ -265,7 +265,7 @@ static int uart_close(int fd)
     return 0;
 }
 
-static int uart_fcntl(int fd, int cmd, va_list args)
+static int uart_fcntl(int fd, int cmd, int arg)
 {
     assert(fd >=0 && fd < 3);
     int result = 0;
@@ -274,7 +274,6 @@ static int uart_fcntl(int fd, int cmd, va_list args)
             result |= O_NONBLOCK;
         }
     } else if (cmd == F_SETFL) {
-        int arg = va_arg(args, int);
         s_non_blocking[fd] = (arg & O_NONBLOCK) != 0;
     } else {
         // unsupported operation