Hi Pavel, > From: Pavel Machek, Sent: Tuesday, July 30, 2019 6:52 PM > > Hi! > > Code does strcmps, but does not actually check count. So AFAICT > writing "host-I-don't-want-I-need-peripheral" into the file will > succeed and turn it into host mode. > > Also data beyond count in buf are going to be accessed. Thank you for the report. I think the driver should use sysfs_streq() helper instead of strncmp() on the sysfs function. So, I'll submit such a patch later. Best regards, Yoshihiro Shimoda > Best regards, > Pavel > > static ssize_t role_store(struct device *dev, struct device_attribute *attr, > const char *buf, size_t count) > { > struct rcar_gen3_chan *ch = dev_get_drvdata(dev); > bool is_b_device; > enum phy_mode cur_mode, new_mode; > > if (!ch->is_otg_channel || !rcar_gen3_is_any_rphy_initialized(ch)) > return -EIO; > > /* FIXME, this is wrong */ > if (!strncmp(buf, "host", strlen("host"))) > new_mode = PHY_MODE_USB_HOST; > else if (!strncmp(buf, "peripheral", strlen("peripheral"))) > new_mode = PHY_MODE_USB_DEVICE; > else > return -EINVAL; > > > -- > (english) http://www.livejournal.com/~pavelmachek > (cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html