FAILED: patch "[PATCH] USB: serial: ti_usb_3410_5052: fix array underflow in" failed to apply to 4.4-stable tree

The patch below does not apply to the 4.4-stable tree.
If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <[email protected]>.

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From: Johan Hovold <[email protected]>
Date: Tue, 21 Aug 2018 11:59:53 +0200
Subject: [PATCH] USB: serial: ti_usb_3410_5052: fix array underflow in
completion handler

Similarly to a recently reported bug in io_ti, 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).

index 3010878f7f8e..e3c5832337e0 100644
@@ -1119,7 +1119,7 @@ static void ti_break(struct tty_struct *tty, int break_state)
 
 static int ti_get_port_from_code(unsigned char code)
 {
-	return (code >> 4) - 3;
+	return (code >> 6) & 0x01;
 }
 
 static int ti_get_func_from_code(unsigned char code)

commit 5dfdd24eb3d39d815bc952ae98128e967c9bba49 upstream.

Similarly to a recently reported bug in io_ti, 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/ti_usb_3410_5052.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

index 98f35c656c02..0cd247f75b8b 100644
@@ -227,7 +227,7 @@ struct ti_interrupt {
 } __attribute__((packed));
 
 /* Interrupt codes */
-#define TI_GET_PORT_FROM_CODE(c)	(((c) >> 4) - 3)
+#define TI_GET_PORT_FROM_CODE(c)	(((c) >> 6) & 0x01)
 #define TI_GET_FUNC_FROM_CODE(c)	((c) & 0x0f)
 #define TI_CODE_HARDWARE_ERROR		0xFF
 #define TI_CODE_DATA_ERROR		0x03

2.19.0

Thanks, now queued up.

greg k-h