Commit b972b68c authored Jun 30, 2006 by David Brownell Committed by Greg Kroah-Hartman Jul 12, 2006

[PATCH] USB: ehci: fix bogus alteration of a local variable

In a rare and all-but-unused path, the EHCI driver could reuse a variable
in a way that'd make trouble. Specifically, if the first root hub port
gets an overcurrent event (rare) during a remote wakeup scenario (all but
unused in today's Linux, except for folk working with suspend-to-RAM and
similar sleep states), that would look like a fatal error which would shut
down the controller. Fix by not reusing that variable.

Spotted by Per Hallsmark <saxofon@musiker.nu>
Fixes http://bugzilla.kernel.org/show_bug.cgi?id=6661

Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

parent 69de51fd

drivers/usb/host/ehci-hcd.c

+4 −3

Original line number	Diff line number	Diff line
		@@ -625,10 +625,11 @@ static irqreturn_t ehci_irq (struct usb_hcd hcd, struct pt_regs regs)
		writel (status \| CMD_RUN, &ehci->regs->command);

		while (i--) {
		status = readl (&ehci->regs->port_status [i]);
		if (status & PORT_OWNER)
		int pstatus = readl (&ehci->regs->port_status [i]);

		if (pstatus & PORT_OWNER)
		continue;
		if (!(status & PORT_RESUME)
		if (!(pstatus & PORT_RESUME)
		\|\| ehci->reset_done [i] != 0)
		continue;

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