phy: renesas: rcar-gen3-usb2: Fix sysfs interface of "role"

Since the role_store() uses strncmp(), it's possible to refer
out-of-memory if the sysfs data size is smaller than strlen("host").
This patch fixes it by using sysfs_streq() instead of strncmp().

Reported-by: Pavel Machek <pavel@denx.de>
Fixes: 9bb86777fb ("phy: rcar-gen3-usb2: add sysfs for usb role swap")
Cc: <stable@vger.kernel.org> # v4.10+
Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Pavel Machek <pavel@denx.de>
Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
This commit is contained in:
Yoshihiro Shimoda 2019-10-07 16:55:10 +09:00 committed by Kishon Vijay Abraham I
parent a8a24429dd
commit 4bd5ead82d

View File

@ -21,6 +21,7 @@
#include <linux/platform_device.h>
#include <linux/pm_runtime.h>
#include <linux/regulator/consumer.h>
#include <linux/string.h>
#include <linux/usb/of.h>
#include <linux/workqueue.h>
@ -320,9 +321,9 @@ static ssize_t role_store(struct device *dev, struct device_attribute *attr,
if (!ch->is_otg_channel || !rcar_gen3_is_any_rphy_initialized(ch))
return -EIO;
if (!strncmp(buf, "host", strlen("host")))
if (sysfs_streq(buf, "host"))
new_mode = PHY_MODE_USB_HOST;
else if (!strncmp(buf, "peripheral", strlen("peripheral")))
else if (sysfs_streq(buf, "peripheral"))
new_mode = PHY_MODE_USB_DEVICE;
else
return -EINVAL;