[PATCH net v2] ethtool: fix ethtool msg len calculation for pause stats
From: Jakub Kicinski <kuba@kernel.org>
Date: 2021-11-02 22:03:11
Subsystem:
networking drivers, networking [ethtool], networking [general], the rest · Maintainers:
Andrew Lunn, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Andrew Lunn, Linus Torvalds
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: 9a27a33027f2 ("ethtool: add standard pause stats")
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
---
v2: add a define
include/linux/ethtool_netlink.h | 3 +++
include/uapi/linux/ethtool_netlink.h | 4 +++-
net/ethtool/pause.c | 3 +--
3 files changed, 7 insertions(+), 3 deletions(-)
diff --git a/include/linux/ethtool_netlink.h b/include/linux/ethtool_netlink.h
index 1e7bf78cb382..aba348d58ff6 100644
--- a/include/linux/ethtool_netlink.h
+++ b/include/linux/ethtool_netlink.h@@ -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, };
diff --git a/include/uapi/linux/ethtool_netlink.h b/include/uapi/linux/ethtool_netlink.h
index ca5fbb59fa42..999777d32dcf 100644
--- a/include/uapi/linux/ethtool_netlink.h
+++ b/include/uapi/linux/ethtool_netlink.h@@ -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) };
diff --git a/net/ethtool/pause.c b/net/ethtool/pause.c
index 9009f412151e..ee1e5806bc93 100644
--- a/net/ethtool/pause.c
+++ b/net/ethtool/pause.c@@ -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; }
--
2.31.1