Commit f97c3dc3 authored Mar 29, 2018 by Tal Gilboa Committed by David S. Miller Mar 30, 2018

net/dim: Fix int overflow



When calculating difference between samples, the values
are multiplied by 100. Large values may cause int overflow
when multiplied (usually on first iteration).
Fixed by forcing 100 to be of type unsigned long.

Fixes: 4c4dbb4a ("net/mlx5e: Move dynamic interrupt coalescing code to include/linux")
Signed-off-by: Tal Gilboa <talgi@mellanox.com>
Reviewed-by: Andy Gospodarek <gospo@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

parent 52a9692a

include/linux/net_dim.h

+1 −1

Original line number	Diff line number	Diff line
		@@ -231,7 +231,7 @@ static inline void net_dim_exit_parking(struct net_dim *dim)
		}

		#define IS_SIGNIFICANT_DIFF(val, ref) \
		(((100 * abs((val) - (ref))) / (ref)) > 10) /* more than 10% difference */
		(((100UL * abs((val) - (ref))) / (ref)) > 10) /* more than 10% difference */

		static inline int net_dim_stats_compare(struct net_dim_stats *curr,
		struct net_dim_stats *prev)