Commit 80c291c1 authored Oct 07, 2019 by Yoshihiro Shimoda Committed by Greg Kroah-Hartman Dec 17, 2019

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



commit 4bd5ead82d4b877ebe41daf95f28cda53205b039 upstream.

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: 9bb86777 ("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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

parent c6f58dcd

drivers/phy/renesas/phy-rcar-gen3-usb2.c

+3 −2

Original line number	Diff line number	Diff line
		@@ -23,6 +23,7 @@
		#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>

		@@ -241,9 +242,9 @@ static ssize_t role_store(struct device dev, struct device_attribute attr,
		if (!ch->has_otg_pins \|\| !ch->phy->init_count)
		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;