@@ -754,6 +754,7 @@ struct proto {
void (*unhash)(struct sock *sk);
void (*rehash)(struct sock *sk);
int (*get_port)(struct sock *sk, unsigned short snum);
+ void (*clear_sk)(struct sock *sk, int size);
/* Keeping track of sockets in use */
#ifdef CONFIG_PROC_FS
@@ -852,6 +853,9 @@ static inline void __sk_prot_rehash(struct sock *sk)
sk->sk_prot->hash(sk);
}
+void sk_prot_clear_nulls(struct sock *sk, int size);
+void sk_prot_clear_portaddr_nulls(struct sock *sk, int size);
+
/* About 10 seconds */
#define SOCK_DESTROY_TIME (10*HZ)
@@ -1009,6 +1009,36 @@ static void sock_copy(struct sock *nsk, const struct sock *osk)
#endif
}
+/*
+ * caches using SLAB_DESTROY_BY_RCU should let .next pointer from nulls nodes
+ * un-modified. Special care is taken when initializing object to zero.
+ */
+void sk_prot_clear_nulls(struct sock *sk, int size)
+{
+ if (offsetof(struct sock, sk_node.next) != 0)
+ memset(sk, 0, offsetof(struct sock, sk_node.next));
+ memset(&sk->sk_node.pprev, 0,
+ size - offsetof(struct sock, sk_node.pprev));
+}
+
+void sk_prot_clear_portaddr_nulls(struct sock *sk, int size)
+{
+ unsigned long nulls1, nulls2;
+
+ nulls1 = offsetof(struct sock, __sk_common.skc_node.next);
+ nulls2 = offsetof(struct sock, __sk_common.skc_portaddr_node.next);
+ if (nulls1 > nulls2)
+ swap(nulls1, nulls2);
+
+ if (nulls1 != 0)
+ memset((char *)sk, 0, nulls1);
+ memset((char *)sk + nulls1 + sizeof(void *), 0,
+ nulls2 - nulls1 - sizeof(void *));
+ memset((char *)sk + nulls2 + sizeof(void *), 0,
+ size - nulls2 - sizeof(void *));
+}
+
+
static struct sock *sk_prot_alloc(struct proto *prot, gfp_t priority,
int family)
{
@@ -1021,19 +1051,12 @@ static struct sock *sk_prot_alloc(struct proto *prot, gfp_t priority,
if (!sk)
return sk;
if (priority & __GFP_ZERO) {
- /*
- * caches using SLAB_DESTROY_BY_RCU should let
- * sk_node.next un-modified. Special care is taken
- * when initializing object to zero.
- */
- if (offsetof(struct sock, sk_node.next) != 0)
- memset(sk, 0, offsetof(struct sock, sk_node.next));
- memset(&sk->sk_node.pprev, 0,
- prot->obj_size - offsetof(struct sock,
- sk_node.pprev));
+ if (prot->clear_sk)
+ prot->clear_sk(sk, prot->obj_size);
+ else
+ memset(sk, 0, prot->obj_size);
}
- }
- else
+ } else
sk = kmalloc(prot->obj_size, priority);
if (sk != NULL) {
@@ -2331,6 +2354,8 @@ static inline void release_proto_idx(struct proto *prot)
int proto_register(struct proto *prot, int alloc_slab)
{
+ BUG_ON((prot->slab_flags & SLAB_DESTROY_BY_RCU) && !prot->clear_sk);
+
if (alloc_slab) {
prot->slab = kmem_cache_create(prot->name, prot->obj_size, 0,
SLAB_HWCACHE_ALIGN | prot->slab_flags,
@@ -956,6 +956,7 @@ static struct proto dccp_v4_prot = {
.compat_setsockopt = compat_dccp_setsockopt,
.compat_getsockopt = compat_dccp_getsockopt,
#endif
+ .clear_sk = sk_prot_clear_nulls,
};
static const struct net_protocol dccp_v4_protocol = {
@@ -1134,6 +1134,7 @@ static struct proto dccp_v6_prot = {
.compat_setsockopt = compat_dccp_setsockopt,
.compat_getsockopt = compat_dccp_getsockopt,
#endif
+ .clear_sk = sk_prot_clear_nulls,
};
static const struct inet6_protocol dccp_v6_protocol = {
@@ -2627,6 +2627,7 @@ struct proto tcp_prot = {
.compat_setsockopt = compat_tcp_setsockopt,
.compat_getsockopt = compat_tcp_getsockopt,
#endif
+ .clear_sk = sk_prot_clear_nulls,
};
EXPORT_SYMBOL(tcp_prot);
@@ -1899,6 +1899,7 @@ struct proto udp_prot = {
.compat_setsockopt = compat_udp_setsockopt,
.compat_getsockopt = compat_udp_getsockopt,
#endif
+ .clear_sk = sk_prot_clear_portaddr_nulls,
};
EXPORT_SYMBOL(udp_prot);
@@ -57,6 +57,7 @@ struct proto udplite_prot = {
.compat_setsockopt = compat_udp_setsockopt,
.compat_getsockopt = compat_udp_getsockopt,
#endif
+ .clear_sk = sk_prot_clear_portaddr_nulls,
};
EXPORT_SYMBOL(udplite_prot);
@@ -2171,6 +2171,7 @@ struct proto tcpv6_prot = {
.compat_setsockopt = compat_tcp_setsockopt,
.compat_getsockopt = compat_tcp_getsockopt,
#endif
+ .clear_sk = sk_prot_clear_nulls,
};
static const struct inet6_protocol tcpv6_protocol = {
@@ -1477,6 +1477,7 @@ struct proto udpv6_prot = {
.compat_setsockopt = compat_udpv6_setsockopt,
.compat_getsockopt = compat_udpv6_getsockopt,
#endif
+ .clear_sk = sk_prot_clear_portaddr_nulls,
};
static struct inet_protosw udpv6_protosw = {
@@ -55,6 +55,7 @@ struct proto udplitev6_prot = {
.compat_setsockopt = compat_udpv6_setsockopt,
.compat_getsockopt = compat_udpv6_getsockopt,
#endif
+ .clear_sk = sk_prot_clear_portaddr_nulls,
};
static struct inet_protosw udplite6_protosw = {
@@ -142,6 +142,7 @@ static struct proto llc_proto = {
.owner = THIS_MODULE,
.obj_size = sizeof(struct llc_sock),
.slab_flags = SLAB_DESTROY_BY_RCU,
+ .clear_sk = sk_prot_clear_nulls,
};
/**