Commit e2c9e619 authored by Thomas Weißschuh's avatar Thomas Weißschuh Committed by Andrew Morton
Browse files

mm/page_idle: constify 'struct bin_attribute' 

The sysfs core now allows instances of 'struct bin_attribute' to be moved
into read-only memory.  Make use of that to protect them against
accidental or malicious modifications.

Link: https://lkml.kernel.org/r/20241216-sysfs-const-bin_attr-page_idle-v1-1-cc01ecc55196@weissschuh.net


Signed-off-by: default avatarThomas Weißschuh <linux@weissschuh.net>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
parent 1fc10653

mm/page_idle.c

+5 −5
Original line number Diff line number Diff line
@@ -112,7 +112,7 @@ static void page_idle_clear_pte_refs(struct folio *folio) 
}



static ssize_t page_idle_bitmap_read(struct file *file, struct kobject *kobj,

				     struct bin_attribute *attr, char *buf,

				     const struct bin_attribute *attr, char *buf,

				     loff_t pos, size_t count)

{

	u64 *out = (u64 *)buf;
@@ -157,7 +157,7 @@ static ssize_t page_idle_bitmap_read(struct file *file, struct kobject *kobj, 
}



static ssize_t page_idle_bitmap_write(struct file *file, struct kobject *kobj,

				      struct bin_attribute *attr, char *buf,

				      const struct bin_attribute *attr, char *buf,

				      loff_t pos, size_t count)

{

	const u64 *in = (u64 *)buf;
@@ -193,17 +193,17 @@ static ssize_t page_idle_bitmap_write(struct file *file, struct kobject *kobj, 
	return (char *)in - buf;

}



static struct bin_attribute page_idle_bitmap_attr =

static const struct bin_attribute page_idle_bitmap_attr =

		__BIN_ATTR(bitmap, 0600,

			   page_idle_bitmap_read, page_idle_bitmap_write, 0);



static struct bin_attribute *page_idle_bin_attrs[] = {

static const struct bin_attribute *const page_idle_bin_attrs[] = {

	&page_idle_bitmap_attr,

	NULL,

};



static const struct attribute_group page_idle_attr_group = {

	.bin_attrs = page_idle_bin_attrs,

	.bin_attrs_new = page_idle_bin_attrs,

	.name = "page_idle",

};