diff options
Diffstat (limited to 'drivers/acpi/custom_method.c')
| -rw-r--r-- | drivers/acpi/custom_method.c | 17 |
1 files changed, 13 insertions, 4 deletions
diff --git a/drivers/acpi/custom_method.c b/drivers/acpi/custom_method.c index b2ef4c2ec955..d39a9b474727 100644 --- a/drivers/acpi/custom_method.c +++ b/drivers/acpi/custom_method.c @@ -9,18 +9,17 @@ #include <linux/uaccess.h> #include <linux/debugfs.h> #include <linux/acpi.h> +#include <linux/security.h> #include "internal.h" -#define _COMPONENT ACPI_SYSTEM_COMPONENT -ACPI_MODULE_NAME("custom_method"); MODULE_LICENSE("GPL"); static struct dentry *cm_dentry; /* /sys/kernel/debug/acpi/custom_method */ -static ssize_t cm_write(struct file *file, const char __user * user_buf, +static ssize_t cm_write(struct file *file, const char __user *user_buf, size_t count, loff_t *ppos) { static char *buf; @@ -29,6 +28,11 @@ static ssize_t cm_write(struct file *file, const char __user * user_buf, struct acpi_table_header table; acpi_status status; + int ret; + + ret = security_locked_down(LOCKDOWN_ACPI_TABLES); + if (ret) + return ret; if (!(*ppos)) { /* parse the table header to get the table length */ @@ -38,6 +42,8 @@ static ssize_t cm_write(struct file *file, const char __user * user_buf, sizeof(struct acpi_table_header))) return -EFAULT; uncopied_bytes = max_size = table.length; + /* make sure the buf is not allocated */ + kfree(buf); buf = kzalloc(max_size, GFP_KERNEL); if (!buf) return -ENOMEM; @@ -49,8 +55,11 @@ static ssize_t cm_write(struct file *file, const char __user * user_buf, if ((*ppos > max_size) || (*ppos + count > max_size) || (*ppos + count < count) || - (count > uncopied_bytes)) + (count > uncopied_bytes)) { + kfree(buf); + buf = NULL; return -EINVAL; + } if (copy_from_user(buf + (*ppos), user_buf, count)) { kfree(buf); |