Re: [BUG] overflow in net/ipv4/route.c rt_check_expire()

["David S. Miller" <davem@xxxxxxxxxxxxx>]

On Wed, 16 Mar 2005 11:47:34 +0100
Eric Dumazet <dada1@xxxxxxxxxxxxx> wrote:

> The rt_check_expire() has a serious problem on machines with large
> route caches, and a standard HZ value of 1000.
> 
> With default values, ie ip_rt_gc_interval = 60*HZ = 60000 ;
> 
> the loop count :
> 
>      for (t = ip_rt_gc_interval << rt_hash_log; t >= 0;
> 
> 
> overflows (t is a 31 bit value) as soon rt_hash_log is >= 16  (65536
> slots in route cache hash table)
 ...
> I am experimenting some changes that I will share when ready.

Good catch, let us know when you have a patch for review.