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Diffstat (limited to 'net/netlink/af_netlink.c')
-rw-r--r--net/netlink/af_netlink.c39
1 files changed, 28 insertions, 11 deletions
diff --git a/net/netlink/af_netlink.c b/net/netlink/af_netlink.c
index 9f51608b968a..8f060d7f9a0e 100644
--- a/net/netlink/af_netlink.c
+++ b/net/netlink/af_netlink.c
@@ -1031,7 +1031,7 @@ static inline int netlink_compare(struct rhashtable_compare_arg *arg,
const struct netlink_compare_arg *x = arg->key;
const struct netlink_sock *nlk = ptr;
- return nlk->rhash_portid != x->portid ||
+ return nlk->portid != x->portid ||
!net_eq(sock_net(&nlk->sk), read_pnet(&x->pnet));
}
@@ -1057,7 +1057,7 @@ static int __netlink_insert(struct netlink_table *table, struct sock *sk)
{
struct netlink_compare_arg arg;
- netlink_compare_arg_init(&arg, sock_net(sk), nlk_sk(sk)->rhash_portid);
+ netlink_compare_arg_init(&arg, sock_net(sk), nlk_sk(sk)->portid);
return rhashtable_lookup_insert_key(&table->hash, &arg,
&nlk_sk(sk)->node,
netlink_rhashtable_params);
@@ -1110,8 +1110,8 @@ static int netlink_insert(struct sock *sk, u32 portid)
lock_sock(sk);
- err = -EBUSY;
- if (nlk_sk(sk)->portid)
+ err = nlk_sk(sk)->portid == portid ? 0 : -EBUSY;
+ if (nlk_sk(sk)->bound)
goto err;
err = -ENOMEM;
@@ -1119,7 +1119,7 @@ static int netlink_insert(struct sock *sk, u32 portid)
unlikely(atomic_read(&table->hash.nelems) >= UINT_MAX))
goto err;
- nlk_sk(sk)->rhash_portid = portid;
+ nlk_sk(sk)->portid = portid;
sock_hold(sk);
err = __netlink_insert(table, sk);
@@ -1135,7 +1135,9 @@ static int netlink_insert(struct sock *sk, u32 portid)
goto err;
}
- nlk_sk(sk)->portid = portid;
+ /* We need to ensure that the socket is hashed and visible. */
+ smp_wmb();
+ nlk_sk(sk)->bound = portid;
err:
release_sock(sk);
@@ -1521,6 +1523,7 @@ static int netlink_bind(struct socket *sock, struct sockaddr *addr,
struct sockaddr_nl *nladdr = (struct sockaddr_nl *)addr;
int err;
long unsigned int groups = nladdr->nl_groups;
+ bool bound;
if (addr_len < sizeof(struct sockaddr_nl))
return -EINVAL;
@@ -1537,9 +1540,14 @@ static int netlink_bind(struct socket *sock, struct sockaddr *addr,
return err;
}
- if (nlk->portid)
+ bound = nlk->bound;
+ if (bound) {
+ /* Ensure nlk->portid is up-to-date. */
+ smp_rmb();
+
if (nladdr->nl_pid != nlk->portid)
return -EINVAL;
+ }
if (nlk->netlink_bind && groups) {
int group;
@@ -1555,7 +1563,10 @@ static int netlink_bind(struct socket *sock, struct sockaddr *addr,
}
}
- if (!nlk->portid) {
+ /* No need for barriers here as we return to user-space without
+ * using any of the bound attributes.
+ */
+ if (!bound) {
err = nladdr->nl_pid ?
netlink_insert(sk, nladdr->nl_pid) :
netlink_autobind(sock);
@@ -1603,7 +1614,10 @@ static int netlink_connect(struct socket *sock, struct sockaddr *addr,
!netlink_allowed(sock, NL_CFG_F_NONROOT_SEND))
return -EPERM;
- if (!nlk->portid)
+ /* No need for barriers here as we return to user-space without
+ * using any of the bound attributes.
+ */
+ if (!nlk->bound)
err = netlink_autobind(sock);
if (err == 0) {
@@ -2444,10 +2458,13 @@ static int netlink_sendmsg(struct socket *sock, struct msghdr *msg, size_t len)
dst_group = nlk->dst_group;
}
- if (!nlk->portid) {
+ if (!nlk->bound) {
err = netlink_autobind(sock);
if (err)
goto out;
+ } else {
+ /* Ensure nlk is hashed and visible. */
+ smp_rmb();
}
/* It's a really convoluted way for userland to ask for mmaped
@@ -3273,7 +3290,7 @@ static inline u32 netlink_hash(const void *data, u32 len, u32 seed)
const struct netlink_sock *nlk = data;
struct netlink_compare_arg arg;
- netlink_compare_arg_init(&arg, sock_net(&nlk->sk), nlk->rhash_portid);
+ netlink_compare_arg_init(&arg, sock_net(&nlk->sk), nlk->portid);
return jhash2((u32 *)&arg, netlink_compare_arg_len / sizeof(u32), seed);
}