fix: Use 'kernel_read' to read from procfs

[lttng-modules.git] / wrapper / random.c

diff --git a/wrapper/random.c b/wrapper/random.c
index da8cb176bce9e5904542834cd4acbc4833eeacb2..d7e53cd140f0a7517fb6ce66b1c492e9959882c8 100644 (file)
--- a/wrapper/random.c
+++ b/wrapper/random.c
@@ -1,13 +1,16 @@
-/*
- * Copyright (C) 2011 Mathieu Desnoyers (mathieu.desnoyers@efficios.com)
+/* SPDX-License-Identifier: (GPL-2.0 or LGPL-2.1)
+ *
+ * wrapper/random.c
  *
  * wrapper around bootid read. Using KALLSYMS to get its address when
  * available, else we need to have a kernel that exports this function to GPL
  * modules.
  *
- * Dual LGPL v2.1/GPL v2 license.
+ * Copyright (C) 2011-2012 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
  */
 
+#include <linux/errno.h>
+
 /* boot_id depends on sysctl */
 #if defined(CONFIG_SYSCTL)
 
@@ -15,7 +18,7 @@
 #include <linux/file.h>
 #include <linux/sched.h>
 #include <linux/uaccess.h>
-#include "random.h"
+#include <wrapper/random.h>
 
 /*
  * Returns string boot id.
@@ -25,21 +28,12 @@ int wrapper_get_bootid(char *bootid)
        struct file *file;
        int ret;
        ssize_t len;
-       mm_segment_t old_fs;
 
        file = filp_open("/proc/sys/kernel/random/boot_id", O_RDONLY, 0);
        if (IS_ERR(file))
                return PTR_ERR(file);
 
-       old_fs = get_fs();
-       set_fs(KERNEL_DS);
-
-       if (!file->f_op || !file->f_op->read) {
-               ret = -EINVAL;
-               goto end;
-       }
-
-       len = file->f_op->read(file, bootid, BOOT_ID_LEN - 1, &file->f_pos);
+       len = kernel_read(file, bootid, BOOT_ID_LEN - 1, &file->f_pos);
        if (len != BOOT_ID_LEN - 1) {
                ret = -EINVAL;
                goto end;
@@ -48,10 +42,10 @@ int wrapper_get_bootid(char *bootid)
        bootid[BOOT_ID_LEN - 1] = '\0';
        ret = 0;
 end:
-       set_fs(old_fs);
        filp_close(file, current->files);
        return ret;
 }
+EXPORT_SYMBOL_GPL(wrapper_get_bootid);
 
 #else
 
@@ -59,5 +53,6 @@ int wrapper_get_bootid(char *bootid)
 {
        return -ENOSYS;
 }
+EXPORT_SYMBOL_GPL(wrapper_get_bootid);
 
 #endif