From mboxrd@z Thu Jan 1 00:00:00 1970 From: Ben Hutchings Subject: [PATCH net-next 4/4] ethtool: Update ethtool_rxnfc::rule_cnt on return from ETHTOOL_GRXCLSRLALL Date: Wed, 07 Sep 2011 00:52:47 +0100 Message-ID: <1315353167.12033.5.camel@bwh-desktop> References: <1315352693.2788.20.camel@bwh-desktop> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit Cc: netdev@vger.kernel.org, Alexander Duyck , Sebastian Poehn , Santwona Behera To: David Miller Return-path: Received: from mail.solarflare.com ([216.237.3.220]:45945 "EHLO exchange.solarflare.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755355Ab1IFXwu (ORCPT ); Tue, 6 Sep 2011 19:52:50 -0400 In-Reply-To: <1315352693.2788.20.camel@bwh-desktop> Sender: netdev-owner@vger.kernel.org List-ID: A user-space process must use ETHTOOL_GRXCLSRLCNT to find the number of classification rules, then allocate a buffer of the right size, then use ETHTOOL_GRXCLSRLALL to fill the buffer. If some other process inserts or deletes a rule between those two operations, the user buffer might turn out to be the wrong size. If it's too small, the return value will be -EMSGSIZE. But if it's too large, there is no indication of this. Fix this by updating the rule_cnt field on return. Signed-off-by: Ben Hutchings --- The change to ixgbe and niu is compile-tested only. The change to gianfar isn't tested at all. Ben. drivers/net/ethernet/freescale/gianfar_ethtool.c | 1 + drivers/net/ethernet/intel/ixgbe/ixgbe_ethtool.c | 2 ++ drivers/net/ethernet/sun/niu.c | 2 ++ include/linux/ethtool.h | 6 +++--- 4 files changed, 8 insertions(+), 3 deletions(-) diff --git a/drivers/net/ethernet/freescale/gianfar_ethtool.c b/drivers/net/ethernet/freescale/gianfar_ethtool.c index 4223830..f30b96f 100644 --- a/drivers/net/ethernet/freescale/gianfar_ethtool.c +++ b/drivers/net/ethernet/freescale/gianfar_ethtool.c @@ -1676,6 +1676,7 @@ static int gfar_get_cls_all(struct gfar_private *priv, } cmd->data = MAX_FILER_IDX; + cmd->rule_cnt = i; return 0; } diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_ethtool.c b/drivers/net/ethernet/intel/ixgbe/ixgbe_ethtool.c index bad2d27..34591c3 100644 --- a/drivers/net/ethernet/intel/ixgbe/ixgbe_ethtool.c +++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_ethtool.c @@ -2279,6 +2279,8 @@ static int ixgbe_get_ethtool_fdir_all(struct ixgbe_adapter *adapter, cnt++; } + cmd->rule_cnt = cnt; + return 0; } diff --git a/drivers/net/ethernet/sun/niu.c b/drivers/net/ethernet/sun/niu.c index 8037059..fff0f8b 100644 --- a/drivers/net/ethernet/sun/niu.c +++ b/drivers/net/ethernet/sun/niu.c @@ -7302,6 +7302,8 @@ static int niu_get_ethtool_tcam_all(struct niu *np, } niu_unlock_parent(np, flags); + nfc->rule_cnt = cnt; + return ret; } diff --git a/include/linux/ethtool.h b/include/linux/ethtool.h index 3df1f3b..ddd536d 100644 --- a/include/linux/ethtool.h +++ b/include/linux/ethtool.h @@ -496,9 +496,9 @@ struct ethtool_rx_flow_spec { * * For %ETHTOOL_GRXCLSRLALL, @rule_cnt specifies the array size of the * user buffer for @rule_locs on entry. On return, @data is the size - * of the rule table and @rule_locs contains the locations of the - * defined rules. Drivers must use the second parameter to get_rxnfc() - * instead of @rule_locs. + * of the rule table, @rule_cnt is the number of defined rules, and + * @rule_locs contains the locations of the defined rules. Drivers + * must use the second parameter to get_rxnfc() instead of @rule_locs. * * For %ETHTOOL_SRXCLSRLINS, @fs specifies the rule to add or update. * @fs.@location specifies the location to use and must not be ignored. -- 1.7.4.4 -- Ben Hutchings, Staff Engineer, Solarflare Not speaking for my employer; that's the marketing department's job. They asked us to note that Solarflare product names are trademarked.