From dae7bfa69b7117da85e5217e1d7ba445559c0106 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Tom=C3=A1=C5=A1=20Rohl=C3=ADnek?=
 <tomas.rohlinek@espressif.com>
Date: Thu, 5 Dec 2024 12:39:59 +0100
Subject: [PATCH] fix(storage/vfs_console): stop new console opens from
 overwriting existing fds

---
 components/vfs/vfs_console.c | 27 ++++++++++++++++++++++++++-
 1 file changed, 26 insertions(+), 1 deletion(-)

diff --git a/components/vfs/vfs_console.c b/components/vfs/vfs_console.c
index caf2ec1aaf..ad57033721 100644
--- a/components/vfs/vfs_console.c
+++ b/components/vfs/vfs_console.c
@@ -1,5 +1,5 @@
 /*
- * SPDX-FileCopyrightText: 2015-2021 Espressif Systems (Shanghai) CO LTD
+ * SPDX-FileCopyrightText: 2015-2024 Espressif Systems (Shanghai) CO LTD
  *
  * SPDX-License-Identifier: Apache-2.0
  */
@@ -12,6 +12,7 @@
 #include "esp_vfs_dev.h"
 #include "esp_private/usb_console.h"
 #include "sdkconfig.h"
+#include <sys/errno.h>
 
 #define STRINGIFY(s) STRINGIFY2(s)
 #define STRINGIFY2(s) #s
@@ -49,8 +50,18 @@ static int primary_vfs_index;
 
 static vfs_console_context_t vfs_console= {0};
 
+static size_t s_open_count = 0;
+
 int console_open(const char * path, int flags, int mode)
 {
+    if (s_open_count > 0) {
+        // Underlying fd is already open, so just increment the open count
+        // and return the same fd
+
+        s_open_count++;
+        return 0;
+    }
+
 // Primary port open
 #if CONFIG_ESP_CONSOLE_UART
     vfs_console.fd_primary = get_vfs_for_path(primary_path)->vfs.open("/"STRINGIFY(CONFIG_ESP_CONSOLE_UART_NUM), flags, mode);
@@ -64,6 +75,8 @@ int console_open(const char * path, int flags, int mode)
 #if CONFIG_ESP_CONSOLE_SECONDARY_USB_SERIAL_JTAG
     vfs_console.fd_secondary = get_vfs_for_path(secondary_path)->vfs.open("/", flags, mode);
 #endif
+
+    s_open_count++;
     return 0;
 }
 
@@ -84,6 +97,18 @@ int console_fstat(int fd, struct stat * st)
 
 int console_close(int fd)
 {
+    if (s_open_count == 0) {
+        errno = EBADF;
+        return -1;
+    }
+
+    s_open_count--;
+
+    // We don't actually close the underlying fd until the open count reaches 0
+    if (s_open_count > 0) {
+        return 0;
+    }
+
     // All function calls are to primary, except from write and close, which will be forwarded to both primary and secondary.
     get_vfs_for_index(primary_vfs_index)->vfs.close(vfs_console.fd_primary);
 #if CONFIG_ESP_CONSOLE_SECONDARY_USB_SERIAL_JTAG