Commit 1aabe578 authored by Jakub Kicinski's avatar Jakub Kicinski Committed by David S. Miller
Browse files

ethtool: fix ethtool msg len calculation for pause stats 



ETHTOOL_A_PAUSE_STAT_MAX is the MAX attribute id,
so we need to subtract non-stats and add one to
get a count (IOW -2+1 == -1).

Otherwise we'll see:

  ethnl cmd 21: calculated reply length 40, but consumed 52

Fixes: 9a27a330 ("ethtool: add standard pause stats")
Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
Reviewed-by: default avatarSaeed Mahameed <saeedm@nvidia.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 9b65b17d

include/linux/ethtool_netlink.h

+3 −0
Original line number Diff line number Diff line
@@ -10,6 +10,9 @@ 
#define __ETHTOOL_LINK_MODE_MASK_NWORDS \

	DIV_ROUND_UP(__ETHTOOL_LINK_MODE_MASK_NBITS, 32)



#define ETHTOOL_PAUSE_STAT_CNT	(__ETHTOOL_A_PAUSE_STAT_CNT -		\

				 ETHTOOL_A_PAUSE_STAT_TX_FRAMES)



enum ethtool_multicast_groups {

	ETHNL_MCGRP_MONITOR,

};

include/uapi/linux/ethtool_netlink.h

+3 −1
Original line number Diff line number Diff line
@@ -411,7 +411,9 @@ enum { 
	ETHTOOL_A_PAUSE_STAT_TX_FRAMES,

	ETHTOOL_A_PAUSE_STAT_RX_FRAMES,



	/* add new constants above here */

	/* add new constants above here

	 * adjust ETHTOOL_PAUSE_STAT_CNT if adding non-stats!

	 */

	__ETHTOOL_A_PAUSE_STAT_CNT,

	ETHTOOL_A_PAUSE_STAT_MAX = (__ETHTOOL_A_PAUSE_STAT_CNT - 1)

};

net/ethtool/pause.c

+1 −2
Original line number Diff line number Diff line
@@ -56,8 +56,7 @@ static int pause_reply_size(const struct ethnl_req_info *req_base, 


	if (req_base->flags & ETHTOOL_FLAG_STATS)

		n += nla_total_size(0) +	/* _PAUSE_STATS */

			nla_total_size_64bit(sizeof(u64)) *

				(ETHTOOL_A_PAUSE_STAT_MAX - 2);

		     nla_total_size_64bit(sizeof(u64)) * ETHTOOL_PAUSE_STAT_CNT;

	return n;

}