From: Scott Bauer Date: Thu, 23 Jun 2016 14:59:47 +0000 (-0600) Subject: HID: hiddev: validate num_values for HIDIOCGUSAGES, HIDIOCSUSAGES commands X-Git-Tag: v3.2.82~26 X-Git-Url: https://git.openpandora.org/cgi-bin/gitweb.cgi?p=pandora-kernel.git;a=commitdiff_plain;h=7cb5ee0e7e734969b39370ac739d473e0ae367bd;hp=53056f82e9d762d0b260cdbcadfd5a10a262e047 HID: hiddev: validate num_values for HIDIOCGUSAGES, HIDIOCSUSAGES commands 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 Signed-off-by: Jiri Kosina Signed-off-by: Ben Hutchings --- diff --git a/drivers/hid/usbhid/hiddev.c b/drivers/hid/usbhid/hiddev.c index 4ef02b269a71..1378ae0d1376 100644 --- a/drivers/hid/usbhid/hiddev.c +++ b/drivers/hid/usbhid/hiddev.c @@ -515,13 +515,13 @@ static noinline int hiddev_ioctl_usage(struct hiddev *hiddev, unsigned int cmd, 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];