This is a note to let you know that I've just added the patch titled
USB: gadget: dummy-hcd: Fix errors in port-reset handling
to my usb git tree which can be found at git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git in the usb-linus branch.
The patch will show up in the next release of the linux-next tree (usually sometime within the next 24 hours during the week.)
The patch will hopefully also be merged in Linus's tree for the next -rc kernel release.
If you have any questions about this process, please let me know.
From 6e6aa61d81194c01283880950df563b1b9abec46 Mon Sep 17 00:00:00 2001
From: Alan Stern stern@rowland.harvard.edu Date: Wed, 13 Jan 2021 14:45:10 -0500 Subject: USB: gadget: dummy-hcd: Fix errors in port-reset handling
Commit c318840fb2a4 ("USB: Gadget: dummy-hcd: Fix shift-out-of-bounds bug") messed up the way dummy-hcd handles requests to turn on the RESET port feature (I didn't notice that the original switch case ended with a fallthrough). The call to set_link_state() was inadvertently removed, as was the code to set the USB_PORT_STAT_RESET flag when the speed is USB2.
In addition, the original code never checked whether the port was connected before handling the port-reset request. There was a check for the port being powered, but it was removed by that commit! In practice this doesn't matter much because the kernel doesn't try to reset disconnected ports, but it's still bad form.
This patch fixes these problems by changing the fallthrough to break, adding back in the missing set_link_state() call, setting the port-reset status flag, adding a port-is-connected test, and removing a redundant assignment statement.
Fixes: c318840fb2a4 ("USB: Gadget: dummy-hcd: Fix shift-out-of-bounds bug") CC: stable@vger.kernel.org Acked-by: Felipe Balbi balbi@kernel.org Signed-off-by: Alan Stern stern@rowland.harvard.edu Link: https://lore.kernel.org/r/20210113194510.GA1290698@rowland.harvard.edu Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/usb/gadget/udc/dummy_hcd.c | 10 +++++++--- 1 file changed, 7 insertions(+), 3 deletions(-)
diff --git a/drivers/usb/gadget/udc/dummy_hcd.c b/drivers/usb/gadget/udc/dummy_hcd.c index 1a953f44183a..57067763b100 100644 --- a/drivers/usb/gadget/udc/dummy_hcd.c +++ b/drivers/usb/gadget/udc/dummy_hcd.c @@ -2270,17 +2270,20 @@ static int dummy_hub_control( } fallthrough; case USB_PORT_FEAT_RESET: + if (!(dum_hcd->port_status & USB_PORT_STAT_CONNECTION)) + break; /* if it's already enabled, disable */ if (hcd->speed == HCD_USB3) { - dum_hcd->port_status = 0; dum_hcd->port_status = (USB_SS_PORT_STAT_POWER | USB_PORT_STAT_CONNECTION | USB_PORT_STAT_RESET); - } else + } else { dum_hcd->port_status &= ~(USB_PORT_STAT_ENABLE | USB_PORT_STAT_LOW_SPEED | USB_PORT_STAT_HIGH_SPEED); + dum_hcd->port_status |= USB_PORT_STAT_RESET; + } /* * We want to reset device status. All but the * Self powered feature @@ -2292,7 +2295,8 @@ static int dummy_hub_control( * interval? Is it still 50msec as for HS? */ dum_hcd->re_timeout = jiffies + msecs_to_jiffies(50); - fallthrough; + set_link_state(dum_hcd); + break; case USB_PORT_FEAT_C_CONNECTION: case USB_PORT_FEAT_C_RESET: case USB_PORT_FEAT_C_ENABLE: