ACPI / EC: access user space with get_user()/put_user() (ecde3003) · Commits · 戴 / test

drivers/acpi/ec_sys.c

+14 −4

Original line number	Diff line number	Diff line
		@@ -12,6 +12,7 @@
		#include <linux/acpi.h>
		#include <linux/debugfs.h>
		#include <linux/module.h>
		#include <linux/uaccess.h>
		#include "internal.h"

		MODULE_AUTHOR("Thomas Renninger <trenn@suse.de>");
		@@ -34,7 +35,6 @@ static ssize_t acpi_ec_read_io(struct file f, char __user buf,
		* struct acpi_ec ec = ((struct seq_file )f->private_data)->private;
		*/
		unsigned int size = EC_SPACE_SIZE;
		u8 data = (u8 ) buf;
		loff_t init_off = *off;
		int err = 0;

		@@ -47,9 +47,15 @@ static ssize_t acpi_ec_read_io(struct file f, char __user buf,
		size = count;

		while (size) {
		err = ec_read(off, &data[off - init_off]);
		u8 byte_read;
		err = ec_read(*off, &byte_read);
		if (err)
		return err;
		if (put_user(byte_read, buf + *off - init_off)) {
		if (*off - init_off)
		return off - init_off; / partial read */
		return -EFAULT;
		}
		*off += 1;
		size--;
		}
		@@ -65,7 +71,6 @@ static ssize_t acpi_ec_write_io(struct file f, const char __user buf,

		unsigned int size = count;
		loff_t init_off = *off;
		u8 data = (u8 ) buf;
		int err = 0;

		if (*off >= EC_SPACE_SIZE)
		@@ -76,7 +81,12 @@ static ssize_t acpi_ec_write_io(struct file f, const char __user buf,
		}

		while (size) {
		u8 byte_write = data[*off - init_off];
		u8 byte_write;
		if (get_user(byte_write, buf + *off - init_off)) {
		if (*off - init_off)
		return off - init_off; / partial write */
		return -EFAULT;
		}
		err = ec_write(*off, byte_write);
		if (err)
		return err;