Re: [PATCH] net/sched/sch_htb: clamp xstats tokens to fit into 32-bit int

From: David Miller
Date: Tue Jul 19 2016 - 01:45:46 EST

From: Konstantin Khlebnikov <khlebnikov@xxxxxxxxxxxxxx>
Date: Sat, 16 Jul 2016 17:08:56 +0300

> In kernel HTB keeps tokens in signed 64-bit in nanoseconds. In netlink
> protocol these values are converted into pshed ticks (64ns for now) and
> truncated to 32-bit. In struct tc_htb_xstats fields "tokens" and "ctokens"
> are declared as unsigned 32-bit but they could be negative thus tool 'tc'
> prints them as signed. Big values loose higher bits and/or become negative.
> This patch clamps tokens in xstat into range from INT_MIN to INT_MAX.
> In this way it's easier to understand what's going on here.
> Signed-off-by: Konstantin Khlebnikov <khlebnikov@xxxxxxxxxxxxxx>