Hello Peter, thanks for reviewing.
On 21.04.2015 03:32, Peter Chen wrote: > 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 <[email protected]> >> --- >> 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? Otherwise we would have two lines with the term min_t(size_t, sizeof(buf) - 1, count). This would make the code harder to read. >> >> + /* sscanf requires a zero terminated string */ >> + buf[count] = 0; >> + > > I prefer using '\0' If you confirm the rest of the patch is ok, I will send an updated patch. Best regards Heinrich > >> if (sscanf(buf, "%u", &mode) != 1) >> return -EINVAL; >> -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
