From 473e64ee4603671efa1e0785418e56e9ffdfc47b Mon Sep 17 00:00:00 2001 From: Ben Hutchings Date: Tue, 6 Sep 2011 13:52:47 +0000 Subject: ethtool: Update ethtool_rxnfc::rule_cnt on return from ETHTOOL_GRXCLSRLALL 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 Signed-off-by: David S. Miller --- include/linux/ethtool.h | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) (limited to 'include/linux') diff --git a/include/linux/ethtool.h b/include/linux/ethtool.h index 5d4a06accd82..45f00b61c096 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. -- cgit v1.2.3