debugfs: Add read-only/write-only bool file ops
There aren't any read-only or write-only bool file ops, but there
is a caller of debugfs_create_bool() that calls it with mode
equal to 0400. This leads to the possibility of userspace
modifying the file, so let's use the newly created
debugfs_create_mode() helper here to fix this.
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/fs/debugfs/file.c b/fs/debugfs/file.c
index e8e73ae..8450549 100644
--- a/fs/debugfs/file.c
+++ b/fs/debugfs/file.c
@@ -450,6 +450,18 @@
.llseek = default_llseek,
};
+static const struct file_operations fops_bool_ro = {
+ .read = debugfs_read_file_bool,
+ .open = simple_open,
+ .llseek = default_llseek,
+};
+
+static const struct file_operations fops_bool_wo = {
+ .write = debugfs_write_file_bool,
+ .open = simple_open,
+ .llseek = default_llseek,
+};
+
/**
* debugfs_create_bool - create a debugfs file that is used to read and write a boolean value
* @name: a pointer to a string containing the name of the file to create.
@@ -477,7 +489,8 @@
struct dentry *debugfs_create_bool(const char *name, umode_t mode,
struct dentry *parent, bool *value)
{
- return debugfs_create_file(name, mode, parent, value, &fops_bool);
+ return debugfs_create_mode(name, mode, parent, value, &fops_bool,
+ &fops_bool_ro, &fops_bool_wo);
}
EXPORT_SYMBOL_GPL(debugfs_create_bool);