From d27c66adb4c0b16c817f71ba96e90f322e7419af Mon Sep 17 00:00:00 2001
From: Khalid Masum <khalid.masum.92@gmail.com>
Date: Thu, 25 Aug 2022 01:38:13 +0600
Subject: [PATCH] usb: ehci: Use endpoint in URB to get maxpacket
usb_maxpacket() looks up the endpoint number in the pipe which can fail
if the interface or configuration changes before the routine is called.
This is unexpected and may even cause a modulo by zero afterwards.
So use usb_endpoint_maxp() routine which uses the endpoint stored in URB
to get the maxpacket.
Suggested-by: Alan Stern <stern@rowland.harvard.edu>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Khalid Masum <khalid.masum.92@gmail.com>
Addresses-Coverity: 744857 ("Division or modulo by zero")
Addresses-Coverity: 1487371 ("Division or modulo by zero")
Link: https://lore.kernel.org/r/20220824193813.13129-1-khalid.masum.92@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
drivers/usb/host/ehci-q.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/drivers/usb/host/ehci-q.c b/drivers/usb/host/ehci-q.c
index 807e64991e3ea..666f5c4db25a8 100644
--- a/drivers/usb/host/ehci-q.c
+++ b/drivers/usb/host/ehci-q.c
@@ -645,7 +645,7 @@ qh_urb_transaction (
token |= (1 /* "in" */ << 8);
/* else it's already initted to "out" pid (0 << 8) */
- maxpacket = usb_maxpacket(urb->dev, urb->pipe);
+ maxpacket = usb_endpoint_maxp(&urb->ep->desc);
/*
* buffer gets wrapped in one or more qtds;
@@ -1218,7 +1218,7 @@ static int ehci_submit_single_step_set_feature(
token |= (1 /* "in" */ << 8); /*This is IN stage*/
- maxpacket = usb_maxpacket(urb->dev, urb->pipe);
+ maxpacket = usb_endpoint_maxp(&urb->ep->desc);
qtd_fill(ehci, qtd, buf, len, token, maxpacket);
--
2.30.2