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: 9a27a33027 ("ethtool: add standard pause stats")
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Reviewed-by: Saeed Mahameed <saeedm@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Jakub Kicinski 2021-11-02 15:02:36 -07:00 committed by David S. Miller
parent 9b65b17db7
commit 1aabe578dd
3 changed files with 7 additions and 3 deletions

View File

@ -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,
};

View File

@ -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)
};

View File

@ -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;
}