patch "USB: serial: io_ti: fix array underflow in completion handler" added to usb-linus

This is a note to let you know that I've just added the patch titled

USB: serial: io_ti: fix array underflow in completion handler

to my usb git tree which can be found at
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git
in the usb-linus branch.

The patch will show up in the next release of the linux-next tree (usually sometime within the next 24 hours during the week.)

The patch will hopefully also be merged in Linus's tree for the next -rc kernel release.

If you have any questions about this process, please let me know.

From: Johan Hovold <[email protected]>
Date: Tue, 21 Aug 2018 11:59:52 +0200
Subject: USB: serial: io_ti: fix array underflow in completion handler

As reported by Dan Carpenter, a malicious USB device could set port_number to a negative value and we would underflow the port array in the interrupt completion handler.

As these devices only have one or two ports, fix this by making sure we only consider the seventh bit when determining the port number (and ignore bits 0xb0 which are typically set to 0x30).

---
 drivers/usb/serial/io_ti.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

index e53c68261017..9bbcee37524e 100644
@@ -173,7 +173,7 @@ struct ump_interrupt {
 }  __attribute__((packed));
 
 
-#define TIUMP_GET_PORT_FROM_CODE(c)	(((c) >> 4) - 3)
+#define TIUMP_GET_PORT_FROM_CODE(c)	(((c) >> 6) & 0x01)
 #define TIUMP_GET_FUNC_FROM_CODE(c)	((c) & 0x0f)
 #define TIUMP_INTERRUPT_CODE_LSR	0x03
 #define TIUMP_INTERRUPT_CODE_MSR	0x04

2.18.0