From: Hadar Hen Zion <hadarh@xxxxxxxxxxxx>
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 <hadarh@xxxxxxxxxxxx>
Signed-off-by: Jiri Pirko <jiri@xxxxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
net/sched/cls_flower.c | 28 +++++++++++++---------------
1 file changed, 13 insertions(+), 15 deletions(-)
--- a/net/sched/cls_flower.c
+++ b/net/sched/cls_flower.c
@@ -351,12 +351,10 @@ static int fl_init_hashtable(struct cls_
#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_
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_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);
}
