From: Alan Stern stern@rowland.harvard.edu
[ Upstream commit ca5cbc8b02f9b21cc8cd1ab36668763ec34f9ee8 ]
The early-exit pathway in hub_activate, added by commit e50293ef9775 ("USB: fix invalid memory access in hub_activate()") needs improvement. It duplicates code that is already present at the end of the subroutine, and it neglects to undo the effect of a usb_autopm_get_interface_no_resume() call.
This patch fixes both problems by making the early-exit pathway jump directly to the end of the subroutine. It simplifies the code at the end by merging two conditionals that actually test the same condition although they appear different: If type < HUB_INIT3 then type must be either HUB_INIT2 or HUB_INIT, and it can't be HUB_INIT because in that case the subroutine would have exited earlier.
Signed-off-by: Alan Stern stern@rowland.harvard.edu CC: stable@vger.kernel.org #4.4+ Reviewed-by: Viresh Kumar viresh.kumar@linaro.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/usb/core/hub.c | 15 ++++++--------- 1 file changed, 6 insertions(+), 9 deletions(-)
diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c index 164fdeddfc05..9a47a9c8ebb4 100644 --- a/drivers/usb/core/hub.c +++ b/drivers/usb/core/hub.c @@ -1000,11 +1000,8 @@ static void hub_activate(struct usb_hub *hub, enum hub_activation_type type) device_lock(hub->intfdev);
/* Was the hub disconnected while we were waiting? */ - if (hub->disconnected) { - device_unlock(hub->intfdev); - kref_put(&hub->kref, hub_release); - return; - } + if (hub->disconnected) + goto disconnected; if (type == HUB_INIT2) goto init2; goto init3; @@ -1230,12 +1227,12 @@ static void hub_activate(struct usb_hub *hub, enum hub_activation_type type) /* Scan all ports that need attention */ kick_hub_wq(hub);
- /* Allow autosuspend if it was suppressed */ - if (type <= HUB_INIT3) + if (type == HUB_INIT2 || type == HUB_INIT3) { + /* Allow autosuspend if it was suppressed */ + disconnected: usb_autopm_put_interface_async(to_usb_interface(hub->intfdev)); - - if (type == HUB_INIT2 || type == HUB_INIT3) device_unlock(hub->intfdev); + }
kref_put(&hub->kref, hub_release); }