From c66f59ee5050447b3da92d36f5385a847990a894 Mon Sep 17 00:00:00 2001 From: =?utf8?q?Micha=C5=82=20Pecio?= Date: Tue, 7 Jun 2016 12:34:45 +0200 Subject: [PATCH] USB: OHCI: Don't mark EDs as ED_OPER if scheduling fails Since ed_schedule begins with marking the ED as "operational", the ED may be left in such state even if scheduling actually fails. This allows future submission attempts to smuggle this ED to the hardware behind the scheduler's back and without linking it to the ohci->eds_in_use list. The former causes bandwidth saturation and data loss on isoc endpoints, the latter crashes the kernel when attempt is made to unlink such ED from this list. Fix ed_schedule to update ED state only on successful return. Signed-off-by: Michal Pecio Acked-by: Alan Stern Signed-off-by: Greg Kroah-Hartman --- drivers/usb/host/ohci-q.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/usb/host/ohci-q.c b/drivers/usb/host/ohci-q.c index d029bbe9eb36..641fed609911 100644 --- a/drivers/usb/host/ohci-q.c +++ b/drivers/usb/host/ohci-q.c @@ -183,7 +183,6 @@ static int ed_schedule (struct ohci_hcd *ohci, struct ed *ed) { int branch; - ed->state = ED_OPER; ed->ed_prev = NULL; ed->ed_next = NULL; ed->hwNextED = 0; @@ -259,6 +258,8 @@ static int ed_schedule (struct ohci_hcd *ohci, struct ed *ed) /* the HC may not see the schedule updates yet, but if it does * then they'll be properly ordered. */ + + ed->state = ED_OPER; return 0; } -- 2.20.1