diff options
| -rw-r--r-- | net/netlink/af_netlink.c | 39 | ||||
| -rw-r--r-- | net/netlink/af_netlink.h | 2 |
2 files changed, 29 insertions, 12 deletions
diff --git a/net/netlink/af_netlink.c b/net/netlink/af_netlink.c index 9f51608..8f060d7 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); } diff --git a/net/netlink/af_netlink.h b/net/netlink/af_netlink.h index 80b2b75..14437d9 100644 --- a/net/netlink/af_netlink.h +++ b/net/netlink/af_netlink.h @@ -25,7 +25,6 @@ struct netlink_ring { struct netlink_sock { /* struct sock has to be the first member of netlink_sock */ struct sock sk; - u32 rhash_portid; u32 portid; u32 dst_portid; u32 dst_group; @@ -36,6 +35,7 @@ struct netlink_sock { unsigned long state; size_t max_recvmsg_len; wait_queue_head_t wait; + bool bound; bool cb_running; struct netlink_callback cb; struct mutex *cb_mutex; |
