From: Thinh Nguyen Date: Thu, 14 Jan 2021 08:09:51 +0000 (-0800) Subject: usb: udc: core: Use lock when write to soft_connect X-Git-Tag: v4.4.257~27 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=f42ee7b59d019b62817a17c416f52a8a48a616d1;p=thirdparty%2Fkernel%2Fstable.git usb: udc: core: Use lock when write to soft_connect commit c28095bc99073ddda65e4f31f6ae0d908d4d5cd8 upstream Use lock to guard against concurrent access for soft-connect/disconnect operations when writing to soft_connect sysfs. Fixes: 2ccea03a8f7e ("usb: gadget: introduce UDC Class") Cc: stable@vger.kernel.org Acked-by: Felipe Balbi Signed-off-by: Thinh Nguyen Link: https://lore.kernel.org/r/338ea01fbd69b1985ef58f0f59af02c805ddf189.1610611437.git.Thinh.Nguyen@synopsys.com Signed-off-by: Greg Kroah-Hartman [sudip: manual backporting to old file] Signed-off-by: Sudip Mukherjee Signed-off-by: Greg Kroah-Hartman --- diff --git a/drivers/usb/gadget/udc/udc-core.c b/drivers/usb/gadget/udc/udc-core.c index a6a1678cb9276..c6859fdd74bc2 100644 --- a/drivers/usb/gadget/udc/udc-core.c +++ b/drivers/usb/gadget/udc/udc-core.c @@ -612,10 +612,13 @@ static ssize_t usb_udc_softconn_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")) { @@ -627,10 +630,14 @@ static ssize_t usb_udc_softconn_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(soft_connect, S_IWUSR, NULL, usb_udc_softconn_store);