HID: validate feature and input report details

When dealing with usage_index, be sure to properly use unsigned instead of
int to avoid overflows.

When working on report fields, always validate that their report_counts are
in bounds.
Without this, a HID device could report a malicious feature report that
could trick the driver into a heap overflow:

[  634.885003] usb 1-1: New USB device found, idVendor=0596, idProduct=0500
...
[  676.469629] BUG kmalloc-192 (Tainted: G        W   ): Redzone overwritten

CVE-2013-2897

Cc: stable@vger.kernel.org
Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Acked-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
This commit is contained in:
Benjamin Tissoires
2013-09-11 21:56:57 +02:00
committed by Jiri Kosina
parent 0a9cd0a80a
commit cc6b54aa54
2 changed files with 17 additions and 10 deletions

View File

@@ -485,6 +485,10 @@ static void hidinput_configure_usage(struct hid_input *hidinput, struct hid_fiel
if (field->flags & HID_MAIN_ITEM_CONSTANT)
goto ignore;
/* Ignore if report count is out of bounds. */
if (field->report_count < 1)
goto ignore;
/* only LED usages are supported in output fields */
if (field->report_type == HID_OUTPUT_REPORT &&
(usage->hid & HID_USAGE_PAGE) != HID_UP_LED) {
@@ -1236,7 +1240,11 @@ static void report_features(struct hid_device *hid)
rep_enum = &hid->report_enum[HID_FEATURE_REPORT];
list_for_each_entry(rep, &rep_enum->report_list, list)
for (i = 0; i < rep->maxfield; i++)
for (i = 0; i < rep->maxfield; i++) {
/* Ignore if report count is out of bounds. */
if (rep->field[i]->report_count < 1)
continue;
for (j = 0; j < rep->field[i]->maxusage; j++) {
/* Verify if Battery Strength feature is available */
hidinput_setup_battery(hid, HID_FEATURE_REPORT, rep->field[i]);
@@ -1245,6 +1253,7 @@ static void report_features(struct hid_device *hid)
drv->feature_mapping(hid, rep->field[i],
rep->field[i]->usage + j);
}
}
}
static struct hid_input *hidinput_allocate(struct hid_device *hid)