[PATCH net 06/14] netfilter: ipset: Don't use test_bit() in lockless RCU readers in bitmap types

[Pablo Neira Ayuso <pablo@netfilter.org>]

From: Jozsef Kadlecsik <kadlec@netfilter.org>

The pair of the patch "netfilter: ipset: Don't use test_bit() in lockless
RCU readers in hash types" for the bitmap types.

Fixes: 02a3231b6d82 ("netfilter: nf_conntrack_expect: store netns and zone in expectation")
Fixes: b0da3905bb1e ("netfilter: ipset: Bitmap types using the unified code base")
Signed-off-by: Jozsef Kadlecsik <kadlec@netfilter.org>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
---
 net/netfilter/ipset/ip_set_bitmap_gen.h   | 4 +++-
 net/netfilter/ipset/ip_set_bitmap_ip.c    | 2 +-
 net/netfilter/ipset/ip_set_bitmap_ipmac.c | 2 +-
 net/netfilter/ipset/ip_set_bitmap_port.c  | 2 +-
 4 files changed, 6 insertions(+), 4 deletions(-)

diff --git a/net/netfilter/ipset/ip_set_bitmap_gen.h b/net/netfilter/ipset/ip_set_bitmap_gen.h
index 798c7993635e..bb9b5bed10e1 100644
--- a/net/netfilter/ipset/ip_set_bitmap_gen.h
+++ b/net/netfilter/ipset/ip_set_bitmap_gen.h
@@ -165,6 +165,7 @@ mtype_add(struct ip_set *set, void *value, const struct ip_set_ext *ext,
 		ip_set_init_skbinfo(ext_skbinfo(x, set), ext);
 
 	/* Activate element */
+	smp_mb__before_atomic();
 	set_bit(e->id, map->members);
 	set->elements++;
 
@@ -219,7 +220,7 @@ mtype_list(const struct ip_set *set,
 		cond_resched_rcu();
 		id = cb->args[IPSET_CB_ARG0];
 		x = get_ext(set, map, id);
-		if (!test_bit(id, map->members) ||
+		if (!test_bit_acquire(id, map->members) ||
 		    (SET_WITH_TIMEOUT(set) &&
 #ifdef IP_SET_BITMAP_STORED_TIMEOUT
 		     mtype_is_filled(x) &&
@@ -278,6 +279,7 @@ mtype_gc(struct timer_list *t)
 			x = get_ext(set, map, id);
 			if (ip_set_timeout_expired(ext_timeout(x, set))) {
 				clear_bit(id, map->members);
+				smp_mb__after_atomic();
 				ip_set_ext_destroy(set, x);
 				set->elements--;
 			}
diff --git a/net/netfilter/ipset/ip_set_bitmap_ip.c b/net/netfilter/ipset/ip_set_bitmap_ip.c
index 5988b9bb9029..ac7febce074f 100644
--- a/net/netfilter/ipset/ip_set_bitmap_ip.c
+++ b/net/netfilter/ipset/ip_set_bitmap_ip.c
@@ -67,7 +67,7 @@ static int
 bitmap_ip_do_test(const struct bitmap_ip_adt_elem *e,
 		  struct bitmap_ip *map, size_t dsize)
 {
-	return !!test_bit(e->id, map->members);
+	return !!test_bit_acquire(e->id, map->members);
 }
 
 static int
diff --git a/net/netfilter/ipset/ip_set_bitmap_ipmac.c b/net/netfilter/ipset/ip_set_bitmap_ipmac.c
index 752f59ef8744..5921fd9d2dca 100644
--- a/net/netfilter/ipset/ip_set_bitmap_ipmac.c
+++ b/net/netfilter/ipset/ip_set_bitmap_ipmac.c
@@ -86,7 +86,7 @@ bitmap_ipmac_do_test(const struct bitmap_ipmac_adt_elem *e,
 {
 	const struct bitmap_ipmac_elem *elem;
 
-	if (!test_bit(e->id, map->members))
+	if (!test_bit_acquire(e->id, map->members))
 		return 0;
 	elem = get_const_elem(map->extensions, e->id, dsize);
 	if (e->add_mac && elem->filled == MAC_FILLED)
diff --git a/net/netfilter/ipset/ip_set_bitmap_port.c b/net/netfilter/ipset/ip_set_bitmap_port.c
index 7138e080def4..ca875c982424 100644
--- a/net/netfilter/ipset/ip_set_bitmap_port.c
+++ b/net/netfilter/ipset/ip_set_bitmap_port.c
@@ -58,7 +58,7 @@ static int
 bitmap_port_do_test(const struct bitmap_port_adt_elem *e,
 		    const struct bitmap_port *map, size_t dsize)
 {
-	return !!test_bit(e->id, map->members);
+	return !!test_bit_acquire(e->id, map->members);
 }
 
 static int
-- 
2.47.3