From 0869a49fe44d9c7b9a3828bfa18cda157b49952d Mon Sep 17 00:00:00 2001 From: Hadar Hen Zion Date: Wed, 17 Aug 2016 13:36:12 +0300 Subject: net_sched: flower: Avoid dissection of unmasked keys commit 339ba878cfb01b68de3d281ba33fd5e4c9f76546 upstream. The current flower implementation checks the mask range and set all the keys included in that range as "used_keys", even if a specific key in the range has a zero mask. This behavior can cause a false positive return value of dissector_uses_key function and unnecessary dissection in __skb_flow_dissect. This patch checks explicitly the mask of each key and "used_keys" will be set accordingly. Fixes: 77b9900ef53a ('tc: introduce Flower classifier') Signed-off-by: Hadar Hen Zion Signed-off-by: Jiri Pirko Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- net/sched/cls_flower.c | 28 +++++++++++++--------------- 1 file changed, 13 insertions(+), 15 deletions(-) (limited to 'net/sched') diff --git a/net/sched/cls_flower.c b/net/sched/cls_flower.c index 5ab8205f988b..a97096a7f801 100644 --- a/net/sched/cls_flower.c +++ b/net/sched/cls_flower.c @@ -351,12 +351,10 @@ static int fl_init_hashtable(struct cls_fl_head *head, #define FL_KEY_MEMBER_OFFSET(member) offsetof(struct fl_flow_key, member) #define FL_KEY_MEMBER_SIZE(member) (sizeof(((struct fl_flow_key *) 0)->member)) -#define FL_KEY_MEMBER_END_OFFSET(member) \ - (FL_KEY_MEMBER_OFFSET(member) + FL_KEY_MEMBER_SIZE(member)) -#define FL_KEY_IN_RANGE(mask, member) \ - (FL_KEY_MEMBER_OFFSET(member) <= (mask)->range.end && \ - FL_KEY_MEMBER_END_OFFSET(member) >= (mask)->range.start) +#define FL_KEY_IS_MASKED(mask, member) \ + memchr_inv(((char *)mask) + FL_KEY_MEMBER_OFFSET(member), \ + 0, FL_KEY_MEMBER_SIZE(member)) \ #define FL_KEY_SET(keys, cnt, id, member) \ do { \ @@ -365,9 +363,9 @@ static int fl_init_hashtable(struct cls_fl_head *head, cnt++; \ } while(0); -#define FL_KEY_SET_IF_IN_RANGE(mask, keys, cnt, id, member) \ +#define FL_KEY_SET_IF_MASKED(mask, keys, cnt, id, member) \ do { \ - if (FL_KEY_IN_RANGE(mask, member)) \ + if (FL_KEY_IS_MASKED(mask, member)) \ FL_KEY_SET(keys, cnt, id, member); \ } while(0); @@ -379,14 +377,14 @@ static void fl_init_dissector(struct cls_fl_head *head, FL_KEY_SET(keys, cnt, FLOW_DISSECTOR_KEY_CONTROL, control); FL_KEY_SET(keys, cnt, FLOW_DISSECTOR_KEY_BASIC, basic); - FL_KEY_SET_IF_IN_RANGE(mask, keys, cnt, - FLOW_DISSECTOR_KEY_ETH_ADDRS, eth); - FL_KEY_SET_IF_IN_RANGE(mask, keys, cnt, - FLOW_DISSECTOR_KEY_IPV4_ADDRS, ipv4); - FL_KEY_SET_IF_IN_RANGE(mask, keys, cnt, - FLOW_DISSECTOR_KEY_IPV6_ADDRS, ipv6); - FL_KEY_SET_IF_IN_RANGE(mask, keys, cnt, - FLOW_DISSECTOR_KEY_PORTS, tp); + FL_KEY_SET_IF_MASKED(&mask->key, keys, cnt, + FLOW_DISSECTOR_KEY_ETH_ADDRS, eth); + FL_KEY_SET_IF_MASKED(&mask->key, keys, cnt, + FLOW_DISSECTOR_KEY_IPV4_ADDRS, ipv4); + FL_KEY_SET_IF_MASKED(&mask->key, keys, cnt, + FLOW_DISSECTOR_KEY_IPV6_ADDRS, ipv6); + FL_KEY_SET_IF_MASKED(&mask->key, keys, cnt, + FLOW_DISSECTOR_KEY_PORTS, tp); skb_flow_dissector_init(&head->dissector, keys, cnt); } -- cgit v1.2.3