[PATCH AUTOSEL 4.9 1/6] HID: hiddev: Fix slab-out-of-bounds write in hiddev_ioctl_usage()
From: Sasha Levin <sashal@kernel.org>
Date: 2020-08-31 15:32:22
Also in:
linux-usb, lkml, stable
Subsystem:
hid core layer, the rest, usb hid/hidbp drivers (usb keyboards, mice, remote controls, ...) · Maintainers:
Jiri Kosina, Benjamin Tissoires, Linus Torvalds
From: Peilin Ye <redacted> [ Upstream commit 25a097f5204675550afb879ee18238ca917cba7a ] `uref->usage_index` is not always being properly checked, causing hiddev_ioctl_usage() to go out of bounds under some cases. Fix it. Reported-by: syzbot+34ee1b45d88571c2fa8b@syzkaller.appspotmail.com Link: https://syzkaller.appspot.com/bug?id=f2aebe90b8c56806b050a20b36f51ed6acabe802 Reviewed-by: Dan Carpenter <redacted> Signed-off-by: Peilin Ye <redacted> Signed-off-by: Jiri Kosina <redacted> Signed-off-by: Sasha Levin <sashal@kernel.org> --- drivers/hid/usbhid/hiddev.c | 4 ++++ 1 file changed, 4 insertions(+)
diff --git a/drivers/hid/usbhid/hiddev.c b/drivers/hid/usbhid/hiddev.c
index dbdd265075daf..7bce23a43907e 100644
--- a/drivers/hid/usbhid/hiddev.c
+++ b/drivers/hid/usbhid/hiddev.c@@ -554,12 +554,16 @@ static noinline int hiddev_ioctl_usage(struct hiddev *hiddev, unsigned int cmd, switch (cmd) { case HIDIOCGUSAGE: + if (uref->usage_index >= field->report_count) + goto inval; uref->value = field->value[uref->usage_index]; if (copy_to_user(user_arg, uref, sizeof(*uref))) goto fault; goto goodreturn; case HIDIOCSUSAGE: + if (uref->usage_index >= field->report_count) + goto inval; field->value[uref->usage_index] = uref->value; goto goodreturn;
--
2.25.1