On Fri, Apr 17, 2015 at 08:04:13AM +0200, Heinrich Schuchardt wrote: > A string written by the user may not be zero terminated. > > sscanf may read memory beyond the buffer if no zero byte > is found. > > Signed-off-by: Heinrich Schuchardt <xypron.glpk@xxxxxx> > --- > drivers/usb/chipidea/debug.c | 6 +++++- > 1 file changed, 5 insertions(+), 1 deletion(-) > > diff --git a/drivers/usb/chipidea/debug.c b/drivers/usb/chipidea/debug.c > index dfb05ed..ef08af3 100644 > --- a/drivers/usb/chipidea/debug.c > +++ b/drivers/usb/chipidea/debug.c > @@ -88,9 +88,13 @@ static ssize_t ci_port_test_write(struct file *file, const char __user *ubuf, > char buf[32]; > int ret; > > - if (copy_from_user(buf, ubuf, min_t(size_t, sizeof(buf) - 1, count))) > + count = min_t(size_t, sizeof(buf) - 1, count); > + if (copy_from_user(buf, ubuf, count)) > return -EFAULT; Any reasons to change above? > > + /* sscanf requires a zero terminated string */ > + buf[count] = 0; > + I prefer using '\0' > if (sscanf(buf, "%u", &mode) != 1) > return -EINVAL; > > -- > 2.1.4 > -- Best Regards, Peter Chen -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
