[PATCH v3 3/3] usb: core: port: do error out if usb_autopm_get_interface() fails

Eugeniu Rosca
2020-02-26T17:51:52Z

Reviewing a fresh portion of coverity defects in USB core
(specifically CID 1458999), Alan Stern noted below in [1]:

On Tue, Feb 25, 2020 at 02:39:23PM -0500, Alan Stern wrote:
> A revised search finds line 997 in drivers/usb/core/hub.c and lines
> 216, 269 in drivers/usb/core/port.c. (I didn't try looking in any
> other directories.) AFAICT all three of these should check the
> return value, although a error message in the kernel log probably
> isn't needed.

Factor out the usb_port_runtime_{resume,suspend}() changes into a
standalone patch to allow conflict-free porting on top of stable v3.9+.

[1] https://lore.kernel.org/lkml/Pine.LNX.4.44L0.2002251419120.1485-100000@iolanthe.rowland.org

Fixes: 971fcd492cebf5 ("usb: add runtime pm support for usb port device")
Cc: stable@vger.kernel.org # v3.9+
Suggested-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Eugeniu Rosca <erosca@de.adit-jv.com>
---
v3:
- Newly submitted
---
drivers/usb/core/port.c | 10 ++++++++--
1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/drivers/usb/core/port.c b/drivers/usb/core/port.c
index bbbb35fa639f..235a7c645503 100644
--- a/drivers/usb/core/port.c
+++ b/drivers/usb/core/port.c
@@ -213,7 +213,10 @@ static int usb_port_runtime_resume(struct device *dev)
if (!port_dev->is_superspeed && peer)
pm_runtime_get_sync(&peer->dev);

- usb_autopm_get_interface(intf);
+ retval = usb_autopm_get_interface(intf);
+ if (retval < 0)
+ return retval;
+
retval = usb_hub_set_port_power(hdev, hub, port1, true);
msleep(hub_power_on_good_delay(hub));
if (udev && !retval) {
@@ -266,7 +269,10 @@ static int usb_port_runtime_suspend(struct device *dev)
if (usb_port_block_power_off)
return -EBUSY;

- usb_autopm_get_interface(intf);
+ retval = usb_autopm_get_interface(intf);
+ if (retval < 0)
+ return retval;
+
retval = usb_hub_set_port_power(hdev, hub, port1, false);
usb_clear_port_feature(hdev, port1, USB_PORT_FEAT_C_CONNECTION);
if (!port_dev->is_superspeed)
--
2.25.1