[PATCH 4.19 49/77] usb: usbip: vhci_hcd: protect shift size

Greg Kroah-Hartman
2021-01-11T13:50:40Z

From: Randy Dunlap <rdunlap@infradead.org>

commit 718bf42b119de652ebcc93655a1f33a9c0d04b3c upstream.

Fix shift out-of-bounds in vhci_hcd.c:

UBSAN: shift-out-of-bounds in ../drivers/usb/usbip/vhci_hcd.c:399:41
shift exponent 768 is too large for 32-bit type 'int'

Fixes: 03cd00d538a6 ("usbip: vhci-hcd: Set the vhci structure up to work")
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Reported-by: syzbot+297d20e437b79283bf6d@syzkaller.appspotmail.com
Cc: Yuyang Du <yuyang.du@intel.com>
Cc: Shuah Khan <shuahkh@osg.samsung.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: linux-usb@vger.kernel.org
Cc: stable <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20201229071309.18418-1-rdunlap@infradead.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
drivers/usb/usbip/vhci_hcd.c | 2 ++
1 file changed, 2 insertions(+)

--- a/drivers/usb/usbip/vhci_hcd.c
+++ b/drivers/usb/usbip/vhci_hcd.c
@@ -396,6 +396,8 @@ static int vhci_hub_control(struct usb_h
default:
usbip_dbg_vhci_rh(" ClearPortFeature: default %x\n",
wValue);
+ if (wValue >= 32)
+ goto error;
vhci_hcd->port_status[rhport] &= ~(1 << wValue);
break;
}