[PATCH] Validate num_values for HIDIOCGUSAGES, HIDIOCSUSAGES commands.
From: Scott Bauer <hidden>
Date: 2016-06-23 15:23:41
Also in:
lkml
Subsystem:
hid core layer, the rest, usb hid/hidbp drivers (usb keyboards, mice, remote controls, ...) · Maintainers:
Jiri Kosina, Benjamin Tissoires, Linus Torvalds
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 <redacted> --- drivers/hid/usbhid/hiddev.c | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-)
diff --git a/drivers/hid/usbhid/hiddev.c b/drivers/hid/usbhid/hiddev.c
index 2f1ddca..700145b 100644
--- a/drivers/hid/usbhid/hiddev.c
+++ b/drivers/hid/usbhid/hiddev.c@@ -516,13 +516,13 @@ 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];
--
1.9.1