Re: [PATCH] wifi: mac80211: fix interger overflow in hwmp_route_info_get()

On Thu, 2024-12-26 at 07:47 +0000, Gavrilov Ilia wrote:

Since the new_metric and last_hop_metric variables can reach the MAX_METRIC(0xffffffff) value, an integer overflow may occur when multiplying them by 10/9. It can lead to incorrect behavior.

Found by InfoTeCS on behalf of Linux Verification Center (linuxtesting.org) with SVACE.

• 			      mult_frac(new_metric, 10, 9) :
  

• 			      mult_frac((u64)new_metric, 10, 9) :
  
  

As you would expect, this doesn't build on 32-bit.

johannnes