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usb: ehci: Use endpoint in URB to get maxpacket

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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>
This commit is contained in:
Khalid Masum 2022-08-25 01:38:13 +06:00 committed by Greg Kroah-Hartman
parent 4348f2e3ab
commit d27c66adb4
1 changed files with 2 additions and 2 deletions
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4
drivers/usb/host/ehci-q.c
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@ -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);