Use lock to guard against concurrent access for soft-connect/disconnect operations when writing to soft_connect sysfs.

Cc: stable@vger.kernel.org Fixes: 2ccea03a8f7e ("usb: gadget: introduce UDC Class") Signed-off-by: Thinh Nguyen Thinh.Nguyen@synopsys.com --- Changes in v3: - Improve flow: avoid assigning "ret = n" early Changes in v2: - Consolidate mutex_unlock to a single place using "goto out"

drivers/usb/gadget/udc/core.c | 13 ++++++++++--- 1 file changed, 10 insertions(+), 3 deletions(-)

diff --git a/drivers/usb/gadget/udc/core.c b/drivers/usb/gadget/udc/core.c index 6a62bbd01324..ea114f922ccf 100644 --- a/drivers/usb/gadget/udc/core.c +++ b/drivers/usb/gadget/udc/core.c @@ -1529,10 +1529,13 @@ static ssize_t soft_connect_store(struct device *dev, struct device_attribute *attr, const char *buf, size_t n) { struct usb_udc *udc = container_of(dev, struct usb_udc, dev); + ssize_t ret;

+ mutex_lock(&udc_lock); if (!udc->driver) { dev_err(dev, "soft-connect without a gadget driver\n"); - return -EOPNOTSUPP; + ret = -EOPNOTSUPP; + goto out; }

if (sysfs_streq(buf, "connect")) { @@ -1543,10 +1546,14 @@ static ssize_t soft_connect_store(struct device *dev, usb_gadget_udc_stop(udc); } else { dev_err(dev, "unsupported command '%s'\n", buf); - return -EINVAL; + ret = -EINVAL; + goto out; }

- return n; + ret = n; +out: + mutex_unlock(&udc_lock); + return ret; } static DEVICE_ATTR_WO(soft_connect);

base-commit: 4e0dcf62ab4cf917d0cbe751b8bf229a065248d4