4.4-stable review patch. If anyone has any objections, please let me know.
------------------ From: Scott Bauer <sba...@plzdonthack.me> commit 93a2001bdfd5376c3dc2158653034c20392d15c5 upstream. This patch validates the num_values parameter from userland during the HIDIOCGUSAGES and HIDIOCSUSAGES commands. Previously, if the report id was set to HID_REPORT_ID_UNKNOWN, we would fail to validate the num_values parameter leading to a heap overflow. Signed-off-by: Scott Bauer <sba...@plzdonthack.me> Signed-off-by: Jiri Kosina <jkos...@suse.cz> Signed-off-by: Greg Kroah-Hartman <gre...@linuxfoundation.org> --- drivers/hid/usbhid/hiddev.c | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) --- a/drivers/hid/usbhid/hiddev.c +++ b/drivers/hid/usbhid/hiddev.c @@ -516,13 +516,13 @@ static noinline int hiddev_ioctl_usage(s goto inval; } else if (uref->usage_index >= field->report_count) goto inval; - - else if ((cmd == HIDIOCGUSAGES || cmd == HIDIOCSUSAGES) && - (uref_multi->num_values > HID_MAX_MULTI_USAGES || - uref->usage_index + uref_multi->num_values > field->report_count)) - goto inval; } + if ((cmd == HIDIOCGUSAGES || cmd == HIDIOCSUSAGES) && + (uref_multi->num_values > HID_MAX_MULTI_USAGES || + uref->usage_index + uref_multi->num_values > field->report_count)) + goto inval; + switch (cmd) { case HIDIOCGUSAGE: uref->value = field->value[uref->usage_index];