platform/x86: thinkpad_acpi: Revert "Use strndup_user() in dispatch_proc_write()"

This reverts commit 35d13c7a05.

This broke procfs interface due to neglecting the fact that
the strings are not coming NULL terminated.

Revert the change till we will have a better clean up.

Fixes: 35d13c7a05 ("platform/x86: thinkpad_acpi: Use strndup_user() in dispatch_proc_write()")
Reported-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
This commit is contained in:
Andy Shevchenko 2020-07-15 12:40:07 +03:00
parent b3a9e3b962
commit e2e90804dc
1 changed files with 11 additions and 3 deletions

View File

@ -885,11 +885,19 @@ static ssize_t dispatch_proc_write(struct file *file,
if (!ibm || !ibm->write)
return -EINVAL;
if (count > PAGE_SIZE - 1)
return -EINVAL;
kernbuf = strndup_user(userbuf, PAGE_SIZE);
if (IS_ERR(kernbuf))
return PTR_ERR(kernbuf);
kernbuf = kmalloc(count + 1, GFP_KERNEL);
if (!kernbuf)
return -ENOMEM;
if (copy_from_user(kernbuf, userbuf, count)) {
kfree(kernbuf);
return -EFAULT;
}
kernbuf[count] = 0;
ret = ibm->write(kernbuf);
if (ret == 0)
ret = count;