diff options
Diffstat (limited to 'net/bluetooth/l2cap_sock.c')
| -rw-r--r-- | net/bluetooth/l2cap_sock.c | 554 |
1 files changed, 429 insertions, 125 deletions
diff --git a/net/bluetooth/l2cap_sock.c b/net/bluetooth/l2cap_sock.c index 686bdc6b35b0..9ee189c815d4 100644 --- a/net/bluetooth/l2cap_sock.c +++ b/net/bluetooth/l2cap_sock.c @@ -29,6 +29,7 @@ #include <linux/module.h> #include <linux/export.h> +#include <linux/filter.h> #include <linux/sched/signal.h> #include <net/bluetooth/bluetooth.h> @@ -45,6 +46,7 @@ static const struct proto_ops l2cap_sock_ops; static void l2cap_sock_init(struct sock *sk, struct sock *parent); static struct sock *l2cap_sock_alloc(struct net *net, struct socket *sock, int proto, gfp_t prio, int kern); +static void l2cap_sock_cleanup_listen(struct sock *parent); bool l2cap_is_socket(struct socket *sock) { @@ -78,7 +80,7 @@ static int l2cap_validate_le_psm(u16 psm) return 0; } -static int l2cap_sock_bind(struct socket *sock, struct sockaddr *addr, int alen) +static int l2cap_sock_bind(struct socket *sock, struct sockaddr_unsized *addr, int alen) { struct sock *sk = sock->sk; struct l2cap_chan *chan = l2cap_pi(sk)->chan; @@ -161,7 +163,11 @@ static int l2cap_sock_bind(struct socket *sock, struct sockaddr *addr, int alen) break; } - if (chan->psm && bdaddr_type_is_le(chan->src_type)) + /* Use L2CAP_MODE_LE_FLOWCTL (CoC) in case of LE address and + * L2CAP_MODE_EXT_FLOWCTL (ECRED) has not been set. + */ + if (chan->psm && bdaddr_type_is_le(chan->src_type) && + chan->mode != L2CAP_MODE_EXT_FLOWCTL) chan->mode = L2CAP_MODE_LE_FLOWCTL; chan->state = BT_BOUND; @@ -172,16 +178,24 @@ done: return err; } -static int l2cap_sock_connect(struct socket *sock, struct sockaddr *addr, +static int l2cap_sock_connect(struct socket *sock, struct sockaddr_unsized *addr, int alen, int flags) { struct sock *sk = sock->sk; struct l2cap_chan *chan = l2cap_pi(sk)->chan; struct sockaddr_l2 la; int len, err = 0; + bool zapped; BT_DBG("sk %p", sk); + lock_sock(sk); + zapped = sock_flag(sk, SOCK_ZAPPED); + release_sock(sk); + + if (zapped) + return -EINVAL; + if (!addr || alen < offsetofend(struct sockaddr, sa_family) || addr->sa_family != AF_BLUETOOTH) return -EINVAL; @@ -232,11 +246,16 @@ static int l2cap_sock_connect(struct socket *sock, struct sockaddr *addr, return -EINVAL; } - if (chan->psm && bdaddr_type_is_le(chan->src_type)) + /* Use L2CAP_MODE_LE_FLOWCTL (CoC) in case of LE address and + * L2CAP_MODE_EXT_FLOWCTL (ECRED) has not been set. + */ + if (chan->psm && bdaddr_type_is_le(chan->src_type) && + chan->mode != L2CAP_MODE_EXT_FLOWCTL) chan->mode = L2CAP_MODE_LE_FLOWCTL; err = l2cap_chan_connect(chan, la.l2_psm, __le16_to_cpu(la.l2_cid), - &la.l2_bdaddr, la.l2_bdaddr_type); + &la.l2_bdaddr, la.l2_bdaddr_type, + READ_ONCE(sk->sk_sndtimeo)); if (err) return err; @@ -274,11 +293,17 @@ static int l2cap_sock_listen(struct socket *sock, int backlog) case L2CAP_MODE_BASIC: case L2CAP_MODE_LE_FLOWCTL: break; + case L2CAP_MODE_EXT_FLOWCTL: + if (!enable_ecred) { + err = -EOPNOTSUPP; + goto done; + } + break; case L2CAP_MODE_ERTM: case L2CAP_MODE_STREAMING: if (!disable_ertm) break; - /* fall through */ + fallthrough; default: err = -EOPNOTSUPP; goto done; @@ -302,7 +327,7 @@ done: } static int l2cap_sock_accept(struct socket *sock, struct socket *newsock, - int flags, bool kern) + struct proto_accept_arg *arg) { DEFINE_WAIT_FUNC(wait, woken_wake_function); struct sock *sk = sock->sk, *nsk; @@ -311,7 +336,7 @@ static int l2cap_sock_accept(struct socket *sock, struct socket *newsock, lock_sock_nested(sk, L2CAP_NESTING_PARENT); - timeo = sock_rcvtimeo(sk, flags & O_NONBLOCK); + timeo = sock_rcvtimeo(sk, arg->flags & O_NONBLOCK); BT_DBG("sk %p timeo %ld", sk, timeo); @@ -389,6 +414,24 @@ static int l2cap_sock_getname(struct socket *sock, struct sockaddr *addr, return sizeof(struct sockaddr_l2); } +static int l2cap_get_mode(struct l2cap_chan *chan) +{ + switch (chan->mode) { + case L2CAP_MODE_BASIC: + return BT_MODE_BASIC; + case L2CAP_MODE_ERTM: + return BT_MODE_ERTM; + case L2CAP_MODE_STREAMING: + return BT_MODE_STREAMING; + case L2CAP_MODE_LE_FLOWCTL: + return BT_MODE_LE_FLOWCTL; + case L2CAP_MODE_EXT_FLOWCTL: + return BT_MODE_EXT_FLOWCTL; + } + + return -EINVAL; +} + static int l2cap_sock_getsockopt_old(struct socket *sock, int optname, char __user *optval, int __user *optlen) { @@ -396,7 +439,8 @@ static int l2cap_sock_getsockopt_old(struct socket *sock, int optname, struct l2cap_chan *chan = l2cap_pi(sk)->chan; struct l2cap_options opts; struct l2cap_conninfo cinfo; - int len, err = 0; + int err = 0; + size_t len; u32 opt; BT_DBG("sk %p", sk); @@ -418,6 +462,20 @@ static int l2cap_sock_getsockopt_old(struct socket *sock, int optname, break; } + /* Only BR/EDR modes are supported here */ + switch (chan->mode) { + case L2CAP_MODE_BASIC: + case L2CAP_MODE_ERTM: + case L2CAP_MODE_STREAMING: + break; + default: + err = -EINVAL; + break; + } + + if (err < 0) + break; + memset(&opts, 0, sizeof(opts)); opts.imtu = chan->imtu; opts.omtu = chan->omtu; @@ -427,7 +485,9 @@ static int l2cap_sock_getsockopt_old(struct socket *sock, int optname, opts.max_tx = chan->max_tx; opts.txwin_size = chan->tx_win; - len = min_t(unsigned int, len, sizeof(opts)); + BT_DBG("mode 0x%2.2x", chan->mode); + + len = min(len, sizeof(opts)); if (copy_to_user(optval, (char *) &opts, len)) err = -EFAULT; @@ -477,7 +537,7 @@ static int l2cap_sock_getsockopt_old(struct socket *sock, int optname, cinfo.hci_handle = chan->conn->hcon->handle; memcpy(cinfo.dev_class, chan->conn->hcon->dev_class, 3); - len = min_t(unsigned int, len, sizeof(cinfo)); + len = min(len, sizeof(cinfo)); if (copy_to_user(optval, (char *) &cinfo, len)) err = -EFAULT; @@ -499,7 +559,8 @@ static int l2cap_sock_getsockopt(struct socket *sock, int level, int optname, struct l2cap_chan *chan = l2cap_pi(sk)->chan; struct bt_security sec; struct bt_power pwr; - int len, err = 0; + u32 phys; + int len, mode, err = 0; BT_DBG("sk %p", sk); @@ -603,6 +664,39 @@ static int l2cap_sock_getsockopt(struct socket *sock, int level, int optname, err = -EFAULT; break; + case BT_PHY: + if (sk->sk_state != BT_CONNECTED) { + err = -ENOTCONN; + break; + } + + phys = hci_conn_get_phy(chan->conn->hcon); + + if (put_user(phys, (u32 __user *) optval)) + err = -EFAULT; + break; + + case BT_MODE: + if (!enable_ecred) { + err = -ENOPROTOOPT; + break; + } + + if (chan->chan_type != L2CAP_CHAN_CONN_ORIENTED) { + err = -EINVAL; + break; + } + + mode = l2cap_get_mode(chan); + if (mode < 0) { + err = mode; + break; + } + + if (put_user(mode, (u8 __user *) optval)) + err = -EFAULT; + break; + default: err = -ENOPROTOOPT; break; @@ -616,12 +710,12 @@ static bool l2cap_valid_mtu(struct l2cap_chan *chan, u16 mtu) { switch (chan->scid) { case L2CAP_CID_ATT: - if (mtu < L2CAP_LE_MIN_MTU) + if (mtu && mtu < L2CAP_LE_MIN_MTU) return false; break; default: - if (mtu < L2CAP_DEFAULT_MIN_MTU) + if (mtu && mtu < L2CAP_DEFAULT_MIN_MTU) return false; } @@ -629,12 +723,12 @@ static bool l2cap_valid_mtu(struct l2cap_chan *chan, u16 mtu) } static int l2cap_sock_setsockopt_old(struct socket *sock, int optname, - char __user *optval, unsigned int optlen) + sockptr_t optval, unsigned int optlen) { struct sock *sk = sock->sk; struct l2cap_chan *chan = l2cap_pi(sk)->chan; struct l2cap_options opts; - int len, err = 0; + int err = 0; u32 opt; BT_DBG("sk %p", sk); @@ -661,11 +755,10 @@ static int l2cap_sock_setsockopt_old(struct socket *sock, int optname, opts.max_tx = chan->max_tx; opts.txwin_size = chan->tx_win; - len = min_t(unsigned int, sizeof(opts), optlen); - if (copy_from_user((char *) &opts, optval, len)) { - err = -EFAULT; + err = copy_safe_from_sockptr(&opts, sizeof(opts), optval, + optlen); + if (err) break; - } if (opts.txwin_size > L2CAP_DEFAULT_EXT_WINDOW) { err = -EINVAL; @@ -677,10 +770,8 @@ static int l2cap_sock_setsockopt_old(struct socket *sock, int optname, break; } - chan->mode = opts.mode; - switch (chan->mode) { - case L2CAP_MODE_LE_FLOWCTL: - break; + /* Only BR/EDR modes are supported here */ + switch (opts.mode) { case L2CAP_MODE_BASIC: clear_bit(CONF_STATE2_DEVICE, &chan->conf_state); break; @@ -688,12 +779,19 @@ static int l2cap_sock_setsockopt_old(struct socket *sock, int optname, case L2CAP_MODE_STREAMING: if (!disable_ertm) break; - /* fall through */ + fallthrough; default: err = -EINVAL; break; } + if (err < 0) + break; + + chan->mode = opts.mode; + + BT_DBG("mode 0x%2.2x", chan->mode); + chan->imtu = opts.imtu; chan->omtu = opts.omtu; chan->fcs = opts.fcs; @@ -703,10 +801,9 @@ static int l2cap_sock_setsockopt_old(struct socket *sock, int optname, break; case L2CAP_LM: - if (get_user(opt, (u32 __user *) optval)) { - err = -EFAULT; + err = copy_safe_from_sockptr(&opt, sizeof(opt), optval, optlen); + if (err) break; - } if (opt & L2CAP_LM_FIPS) { err = -EINVAL; @@ -740,16 +837,57 @@ static int l2cap_sock_setsockopt_old(struct socket *sock, int optname, return err; } +static int l2cap_set_mode(struct l2cap_chan *chan, u8 mode) +{ + switch (mode) { + case BT_MODE_BASIC: + if (bdaddr_type_is_le(chan->src_type)) + return -EINVAL; + mode = L2CAP_MODE_BASIC; + clear_bit(CONF_STATE2_DEVICE, &chan->conf_state); + break; + case BT_MODE_ERTM: + if (!disable_ertm || bdaddr_type_is_le(chan->src_type)) + return -EINVAL; + mode = L2CAP_MODE_ERTM; + break; + case BT_MODE_STREAMING: + if (!disable_ertm || bdaddr_type_is_le(chan->src_type)) + return -EINVAL; + mode = L2CAP_MODE_STREAMING; + break; + case BT_MODE_LE_FLOWCTL: + if (!bdaddr_type_is_le(chan->src_type)) + return -EINVAL; + mode = L2CAP_MODE_LE_FLOWCTL; + break; + case BT_MODE_EXT_FLOWCTL: + /* TODO: Add support for ECRED PDUs to BR/EDR */ + if (!bdaddr_type_is_le(chan->src_type)) + return -EINVAL; + mode = L2CAP_MODE_EXT_FLOWCTL; + break; + default: + return -EINVAL; + } + + chan->mode = mode; + + return 0; +} + static int l2cap_sock_setsockopt(struct socket *sock, int level, int optname, - char __user *optval, unsigned int optlen) + sockptr_t optval, unsigned int optlen) { struct sock *sk = sock->sk; struct l2cap_chan *chan = l2cap_pi(sk)->chan; struct bt_security sec; struct bt_power pwr; struct l2cap_conn *conn; - int len, err = 0; + int err = 0; u32 opt; + u16 mtu; + u8 mode; BT_DBG("sk %p", sk); @@ -772,11 +910,9 @@ static int l2cap_sock_setsockopt(struct socket *sock, int level, int optname, sec.level = BT_SECURITY_LOW; - len = min_t(unsigned int, sizeof(sec), optlen); - if (copy_from_user((char *) &sec, optval, len)) { - err = -EFAULT; + err = copy_safe_from_sockptr(&sec, sizeof(sec), optval, optlen); + if (err) break; - } if (sec.level < BT_SECURITY_LOW || sec.level > BT_SECURITY_FIPS) { @@ -791,10 +927,13 @@ static int l2cap_sock_setsockopt(struct socket *sock, int level, int optname, conn = chan->conn; - /*change security for LE channels */ + /* change security for LE channels */ if (chan->scid == L2CAP_CID_ATT) { - if (smp_conn_security(conn->hcon, sec.level)) + if (smp_conn_security(conn->hcon, sec.level)) { + err = -EINVAL; break; + } + set_bit(FLAG_PENDING_SECURITY, &chan->flags); sk->sk_state = BT_CONFIG; chan->state = BT_CONFIG; @@ -818,10 +957,9 @@ static int l2cap_sock_setsockopt(struct socket *sock, int level, int optname, break; } - if (get_user(opt, (u32 __user *) optval)) { - err = -EFAULT; + err = copy_safe_from_sockptr(&opt, sizeof(opt), optval, optlen); + if (err) break; - } if (opt) { set_bit(BT_SK_DEFER_SETUP, &bt_sk(sk)->flags); @@ -833,10 +971,9 @@ static int l2cap_sock_setsockopt(struct socket *sock, int level, int optname, break; case BT_FLUSHABLE: - if (get_user(opt, (u32 __user *) optval)) { - err = -EFAULT; + err = copy_safe_from_sockptr(&opt, sizeof(opt), optval, optlen); + if (err) break; - } if (opt > BT_FLUSHABLE_ON) { err = -EINVAL; @@ -868,11 +1005,9 @@ static int l2cap_sock_setsockopt(struct socket *sock, int level, int optname, pwr.force_active = BT_POWER_FORCE_ACTIVE_ON; - len = min_t(unsigned int, sizeof(pwr), optlen); - if (copy_from_user((char *) &pwr, optval, len)) { - err = -EFAULT; + err = copy_safe_from_sockptr(&pwr, sizeof(pwr), optval, optlen); + if (err) break; - } if (pwr.force_active) set_bit(FLAG_FORCE_ACTIVE, &chan->flags); @@ -881,28 +1016,11 @@ static int l2cap_sock_setsockopt(struct socket *sock, int level, int optname, break; case BT_CHANNEL_POLICY: - if (get_user(opt, (u32 __user *) optval)) { - err = -EFAULT; - break; - } - - if (opt > BT_CHANNEL_POLICY_AMP_PREFERRED) { - err = -EINVAL; - break; - } - - if (chan->mode != L2CAP_MODE_ERTM && - chan->mode != L2CAP_MODE_STREAMING) { - err = -EOPNOTSUPP; + err = copy_safe_from_sockptr(&opt, sizeof(opt), optval, optlen); + if (err) break; - } - - chan->chan_policy = (u8) opt; - - if (sk->sk_state == BT_CONNECTED && - chan->move_role == L2CAP_MOVE_ROLE_NONE) - l2cap_move_start(chan); + err = -EOPNOTSUPP; break; case BT_SNDMTU: @@ -923,17 +1041,55 @@ static int l2cap_sock_setsockopt(struct socket *sock, int level, int optname, break; } - if (sk->sk_state == BT_CONNECTED) { + if (chan->mode == L2CAP_MODE_LE_FLOWCTL && + sk->sk_state == BT_CONNECTED) { err = -EISCONN; break; } - if (get_user(opt, (u16 __user *) optval)) { - err = -EFAULT; + err = copy_safe_from_sockptr(&mtu, sizeof(mtu), optval, optlen); + if (err) + break; + + if (chan->mode == L2CAP_MODE_EXT_FLOWCTL && + sk->sk_state == BT_CONNECTED) + err = l2cap_chan_reconfigure(chan, mtu); + else + chan->imtu = mtu; + + break; + + case BT_MODE: + if (!enable_ecred) { + err = -ENOPROTOOPT; + break; + } + + BT_DBG("sk->sk_state %u", sk->sk_state); + + if (sk->sk_state != BT_BOUND) { + err = -EINVAL; + break; + } + + if (chan->chan_type != L2CAP_CHAN_CONN_ORIENTED) { + err = -EINVAL; break; } - chan->imtu = opt; + err = copy_safe_from_sockptr(&mode, sizeof(mode), optval, + optlen); + if (err) + break; + + BT_DBG("mode %u", mode); + + err = l2cap_set_mode(chan, mode); + if (err) + break; + + BT_DBG("mode 0x%2.2x", chan->mode); + break; default: @@ -950,6 +1106,7 @@ static int l2cap_sock_sendmsg(struct socket *sock, struct msghdr *msg, { struct sock *sk = sock->sk; struct l2cap_chan *chan = l2cap_pi(sk)->chan; + struct sockcm_cookie sockc; int err; BT_DBG("sock %p, sk %p", sock, sk); @@ -964,6 +1121,14 @@ static int l2cap_sock_sendmsg(struct socket *sock, struct msghdr *msg, if (sk->sk_state != BT_CONNECTED) return -ENOTCONN; + hci_sockcm_init(&sockc, sk); + + if (msg->msg_controllen) { + err = sock_cmsg_send(sk, msg, &sockc); + if (err) + return err; + } + lock_sock(sk); err = bt_sock_wait_ready(sk, msg->msg_flags); release_sock(sk); @@ -971,12 +1136,40 @@ static int l2cap_sock_sendmsg(struct socket *sock, struct msghdr *msg, return err; l2cap_chan_lock(chan); - err = l2cap_chan_send(chan, msg, len); + err = l2cap_chan_send(chan, msg, len, &sockc); l2cap_chan_unlock(chan); return err; } +static void l2cap_publish_rx_avail(struct l2cap_chan *chan) +{ + struct sock *sk = chan->data; + ssize_t avail = sk->sk_rcvbuf - atomic_read(&sk->sk_rmem_alloc); + int expected_skbs, skb_overhead; + + if (avail <= 0) { + l2cap_chan_rx_avail(chan, 0); + return; + } + + if (!chan->mps) { + l2cap_chan_rx_avail(chan, -1); + return; + } + + /* Correct available memory by estimated sk_buff overhead. + * This is significant due to small transfer sizes. However, accept + * at least one full packet if receive space is non-zero. + */ + expected_skbs = DIV_ROUND_UP(avail, chan->mps); + skb_overhead = expected_skbs * sizeof(struct sk_buff); + if (skb_overhead < avail) + l2cap_chan_rx_avail(chan, avail - skb_overhead); + else + l2cap_chan_rx_avail(chan, -1); +} + static int l2cap_sock_recvmsg(struct socket *sock, struct msghdr *msg, size_t len, int flags) { @@ -984,11 +1177,19 @@ static int l2cap_sock_recvmsg(struct socket *sock, struct msghdr *msg, struct l2cap_pinfo *pi = l2cap_pi(sk); int err; + if (unlikely(flags & MSG_ERRQUEUE)) + return sock_recv_errqueue(sk, msg, len, SOL_BLUETOOTH, + BT_SCM_ERROR); + lock_sock(sk); if (sk->sk_state == BT_CONNECT2 && test_bit(BT_SK_DEFER_SETUP, &bt_sk(sk)->flags)) { - if (bdaddr_type_is_le(pi->chan->src_type)) { + if (pi->chan->mode == L2CAP_MODE_EXT_FLOWCTL) { + sk->sk_state = BT_CONNECTED; + pi->chan->state = BT_CONNECTED; + __l2cap_ecred_conn_rsp_defer(pi->chan); + } else if (bdaddr_type_is_le(pi->chan->src_type)) { sk->sk_state = BT_CONNECTED; pi->chan->state = BT_CONNECTED; __l2cap_le_connect_rsp_defer(pi->chan); @@ -1009,28 +1210,33 @@ static int l2cap_sock_recvmsg(struct socket *sock, struct msghdr *msg, else err = bt_sock_recvmsg(sock, msg, len, flags); - if (pi->chan->mode != L2CAP_MODE_ERTM) + if (pi->chan->mode != L2CAP_MODE_ERTM && + pi->chan->mode != L2CAP_MODE_LE_FLOWCTL && + pi->chan->mode != L2CAP_MODE_EXT_FLOWCTL) return err; - /* Attempt to put pending rx data in the socket buffer */ - lock_sock(sk); - if (!test_bit(CONN_LOCAL_BUSY, &pi->chan->conn_state)) - goto done; + l2cap_publish_rx_avail(pi->chan); - if (pi->rx_busy_skb) { - if (!__sock_queue_rcv_skb(sk, pi->rx_busy_skb)) - pi->rx_busy_skb = NULL; - else + /* Attempt to put pending rx data in the socket buffer */ + while (!list_empty(&pi->rx_busy)) { + struct l2cap_rx_busy *rx_busy = + list_first_entry(&pi->rx_busy, + struct l2cap_rx_busy, + list); + if (__sock_queue_rcv_skb(sk, rx_busy->skb) < 0) goto done; + list_del(&rx_busy->list); + kfree(rx_busy); } /* Restore data flow when half of the receive buffer is * available. This avoids resending large numbers of * frames. */ - if (atomic_read(&sk->sk_rmem_alloc) <= sk->sk_rcvbuf >> 1) + if (test_bit(CONN_LOCAL_BUSY, &pi->chan->conn_state) && + atomic_read(&sk->sk_rmem_alloc) <= sk->sk_rcvbuf >> 1) l2cap_chan_busy(pi->chan, 0); done: @@ -1039,7 +1245,7 @@ done: } /* Kill socket (only if zapped and orphan) - * Must be called on unlocked socket. + * Must be called on unlocked socket, with l2cap channel lock. */ static void l2cap_sock_kill(struct sock *sk) { @@ -1048,6 +1254,10 @@ static void l2cap_sock_kill(struct sock *sk) BT_DBG("sk %p state %s", sk, state_to_string(sk->sk_state)); + /* Sock is dead, so set chan data to NULL, avoid other task use invalid + * sock pointer. + */ + l2cap_pi(sk)->chan->data = NULL; /* Kill poor orphan */ l2cap_chan_put(l2cap_pi(sk)->chan); @@ -1107,14 +1317,21 @@ static int l2cap_sock_shutdown(struct socket *sock, int how) struct l2cap_conn *conn; int err = 0; - BT_DBG("sock %p, sk %p", sock, sk); + BT_DBG("sock %p, sk %p, how %d", sock, sk, how); + + /* 'how' parameter is mapped to sk_shutdown as follows: + * SHUT_RD (0) --> RCV_SHUTDOWN (1) + * SHUT_WR (1) --> SEND_SHUTDOWN (2) + * SHUT_RDWR (2) --> SHUTDOWN_MASK (3) + */ + how++; if (!sk) return 0; lock_sock(sk); - if (sk->sk_shutdown) + if ((sk->sk_shutdown & how) == how) goto shutdown_already; BT_DBG("Handling sock shutdown"); @@ -1122,9 +1339,10 @@ static int l2cap_sock_shutdown(struct socket *sock, int how) /* prevent sk structure from being freed whilst unlocked */ sock_hold(sk); - chan = l2cap_pi(sk)->chan; /* prevent chan structure from being freed whilst unlocked */ - l2cap_chan_hold(chan); + chan = l2cap_chan_hold_unless_zero(l2cap_pi(sk)->chan); + if (!chan) + goto shutdown_already; BT_DBG("chan %p state %s", chan, state_to_string(chan->state)); @@ -1137,30 +1355,37 @@ static int l2cap_sock_shutdown(struct socket *sock, int how) * has already been actioned to close the L2CAP * link such as by l2cap_disconnection_req(). */ - if (sk->sk_shutdown) - goto has_shutdown; + if ((sk->sk_shutdown & how) == how) + goto shutdown_matched; } - sk->sk_shutdown = SHUTDOWN_MASK; + /* Try setting the RCV_SHUTDOWN bit, return early if SEND_SHUTDOWN + * is already set + */ + if ((how & RCV_SHUTDOWN) && !(sk->sk_shutdown & RCV_SHUTDOWN)) { + sk->sk_shutdown |= RCV_SHUTDOWN; + if ((sk->sk_shutdown & how) == how) + goto shutdown_matched; + } + + sk->sk_shutdown |= SEND_SHUTDOWN; release_sock(sk); l2cap_chan_lock(chan); - conn = chan->conn; - if (conn) - /* prevent conn structure from being freed */ - l2cap_conn_get(conn); + /* prevent conn structure from being freed */ + conn = l2cap_conn_hold_unless_zero(chan->conn); l2cap_chan_unlock(chan); if (conn) /* mutex lock must be taken before l2cap_chan_lock() */ - mutex_lock(&conn->chan_lock); + mutex_lock(&conn->lock); l2cap_chan_lock(chan); l2cap_chan_close(chan, 0); l2cap_chan_unlock(chan); if (conn) { - mutex_unlock(&conn->chan_lock); + mutex_unlock(&conn->lock); l2cap_conn_put(conn); } @@ -1171,7 +1396,7 @@ static int l2cap_sock_shutdown(struct socket *sock, int how) err = bt_sock_wait_state(sk, BT_CLOSED, sk->sk_lingertime); -has_shutdown: +shutdown_matched: l2cap_chan_put(chan); sock_put(sk); @@ -1190,18 +1415,31 @@ static int l2cap_sock_release(struct socket *sock) { struct sock *sk = sock->sk; int err; + struct l2cap_chan *chan; BT_DBG("sock %p, sk %p", sock, sk); if (!sk) return 0; + lock_sock_nested(sk, L2CAP_NESTING_PARENT); + l2cap_sock_cleanup_listen(sk); + release_sock(sk); + bt_sock_unlink(&l2cap_sk_list, sk); - err = l2cap_sock_shutdown(sock, 2); + err = l2cap_sock_shutdown(sock, SHUT_RDWR); + chan = l2cap_pi(sk)->chan; + + l2cap_chan_hold(chan); + l2cap_chan_lock(chan); sock_orphan(sk); l2cap_sock_kill(sk); + + l2cap_chan_unlock(chan); + l2cap_chan_put(chan); + return err; } @@ -1219,12 +1457,15 @@ static void l2cap_sock_cleanup_listen(struct sock *parent) BT_DBG("child chan %p state %s", chan, state_to_string(chan->state)); + l2cap_chan_hold(chan); l2cap_chan_lock(chan); + __clear_chan_timer(chan); l2cap_chan_close(chan, ECONNRESET); - l2cap_chan_unlock(chan); - l2cap_sock_kill(sk); + + l2cap_chan_unlock(chan); + l2cap_chan_put(chan); } } @@ -1252,7 +1493,7 @@ static struct l2cap_chan *l2cap_sock_new_connection_cb(struct l2cap_chan *chan) l2cap_sock_init(sk, parent); - bt_accept_enqueue(parent, sk); + bt_accept_enqueue(parent, sk, false); release_sock(parent); @@ -1261,18 +1502,25 @@ static struct l2cap_chan *l2cap_sock_new_connection_cb(struct l2cap_chan *chan) static int l2cap_sock_recv_cb(struct l2cap_chan *chan, struct sk_buff *skb) { - struct sock *sk = chan->data; + struct sock *sk; + struct l2cap_pinfo *pi; int err; - lock_sock(sk); + sk = chan->data; + if (!sk) + return -ENXIO; - if (l2cap_pi(sk)->rx_busy_skb) { + pi = l2cap_pi(sk); + lock_sock(sk); + if (chan->mode == L2CAP_MODE_ERTM && !list_empty(&pi->rx_busy)) { err = -ENOMEM; goto done; } if (chan->mode != L2CAP_MODE_ERTM && - chan->mode != L2CAP_MODE_STREAMING) { + chan->mode != L2CAP_MODE_STREAMING && + chan->mode != L2CAP_MODE_LE_FLOWCTL && + chan->mode != L2CAP_MODE_EXT_FLOWCTL) { /* Even if no filter is attached, we could potentially * get errors from security modules, etc. */ @@ -1283,7 +1531,9 @@ static int l2cap_sock_recv_cb(struct l2cap_chan *chan, struct sk_buff *skb) err = __sock_queue_rcv_skb(sk, skb); - /* For ERTM, handle one skb that doesn't fit into the recv + l2cap_publish_rx_avail(chan); + + /* For ERTM and LE, handle a skb that doesn't fit into the recv * buffer. This is important to do because the data frames * have already been acked, so the skb cannot be discarded. * @@ -1292,8 +1542,18 @@ static int l2cap_sock_recv_cb(struct l2cap_chan *chan, struct sk_buff *skb) * acked and reassembled until there is buffer space * available. */ - if (err < 0 && chan->mode == L2CAP_MODE_ERTM) { - l2cap_pi(sk)->rx_busy_skb = skb; + if (err < 0 && + (chan->mode == L2CAP_MODE_ERTM || + chan->mode == L2CAP_MODE_LE_FLOWCTL || + chan->mode == L2CAP_MODE_EXT_FLOWCTL)) { + struct l2cap_rx_busy *rx_busy = + kmalloc(sizeof(*rx_busy), GFP_KERNEL); + if (!rx_busy) { + err = -ENOMEM; + goto done; + } + rx_busy->skb = skb; + list_add_tail(&rx_busy->list, &pi->rx_busy); l2cap_chan_busy(chan, 1); err = 0; } @@ -1308,6 +1568,9 @@ static void l2cap_sock_close_cb(struct l2cap_chan *chan) { struct sock *sk = chan->data; + if (!sk) + return; + l2cap_sock_kill(sk); } @@ -1316,6 +1579,9 @@ static void l2cap_sock_teardown_cb(struct l2cap_chan *chan, int err) struct sock *sk = chan->data; struct sock *parent; + if (!sk) + return; + BT_DBG("chan %p state %s", chan, state_to_string(chan->state)); /* This callback can be called both for server (BT_LISTEN) @@ -1329,8 +1595,6 @@ static void l2cap_sock_teardown_cb(struct l2cap_chan *chan, int err) parent = bt_sk(sk)->parent; - sock_set_flag(sk, SOCK_ZAPPED); - switch (chan->state) { case BT_OPEN: case BT_BOUND: @@ -1357,8 +1621,11 @@ static void l2cap_sock_teardown_cb(struct l2cap_chan *chan, int err) break; } - release_sock(sk); + + /* Only zap after cleanup to avoid use after free race */ + sock_set_flag(sk, SOCK_ZAPPED); + } static void l2cap_sock_state_change_cb(struct l2cap_chan *chan, int state, @@ -1387,7 +1654,15 @@ static struct sk_buff *l2cap_sock_alloc_skb_cb(struct l2cap_chan *chan, if (!skb) return ERR_PTR(err); - skb->priority = sk->sk_priority; + /* Channel lock is released before requesting new skb and then + * reacquired thus we need to recheck channel state. + */ + if (chan->state != BT_CONNECTED) { + kfree_skb(skb); + return ERR_PTR(-ENOTCONN); + } + + skb->priority = READ_ONCE(sk->sk_priority); bt_cb(skb)->l2cap.chan = chan; @@ -1431,6 +1706,9 @@ static void l2cap_sock_resume_cb(struct l2cap_chan *chan) { struct sock *sk = chan->data; + if (!sk) + return; + if (test_and_clear_bit(FLAG_PENDING_SECURITY, &chan->flags)) { sk->sk_state = BT_CONNECTED; chan->state = BT_CONNECTED; @@ -1453,7 +1731,14 @@ static long l2cap_sock_get_sndtimeo_cb(struct l2cap_chan *chan) { struct sock *sk = chan->data; - return sk->sk_sndtimeo; + return READ_ONCE(sk->sk_sndtimeo); +} + +static struct pid *l2cap_sock_get_peer_pid_cb(struct l2cap_chan *chan) +{ + struct sock *sk = chan->data; + + return sk->sk_peer_pid; } static void l2cap_sock_suspend_cb(struct l2cap_chan *chan) @@ -1464,6 +1749,19 @@ static void l2cap_sock_suspend_cb(struct l2cap_chan *chan) sk->sk_state_change(sk); } +static int l2cap_sock_filter(struct l2cap_chan *chan, struct sk_buff *skb) +{ + struct sock *sk = chan->data; + + switch (chan->mode) { + case L2CAP_MODE_ERTM: + case L2CAP_MODE_STREAMING: + return sk_filter(sk, skb); + } + + return 0; +} + static const struct l2cap_ops l2cap_chan_ops = { .name = "L2CAP Socket Interface", .new_connection = l2cap_sock_new_connection_cb, @@ -1477,19 +1775,26 @@ static const struct l2cap_ops l2cap_chan_ops = { .suspend = l2cap_sock_suspend_cb, .set_shutdown = l2cap_sock_set_shutdown_cb, .get_sndtimeo = l2cap_sock_get_sndtimeo_cb, + .get_peer_pid = l2cap_sock_get_peer_pid_cb, .alloc_skb = l2cap_sock_alloc_skb_cb, + .filter = l2cap_sock_filter, }; static void l2cap_sock_destruct(struct sock *sk) { + struct l2cap_rx_busy *rx_busy, *next; + BT_DBG("sk %p", sk); - if (l2cap_pi(sk)->chan) + if (l2cap_pi(sk)->chan) { + l2cap_pi(sk)->chan->data = NULL; l2cap_chan_put(l2cap_pi(sk)->chan); + } - if (l2cap_pi(sk)->rx_busy_skb) { - kfree_skb(l2cap_pi(sk)->rx_busy_skb); - l2cap_pi(sk)->rx_busy_skb = NULL; + list_for_each_entry_safe(rx_busy, next, &l2cap_pi(sk)->rx_busy, list) { + kfree_skb(rx_busy->skb); + list_del(&rx_busy->list); + kfree(rx_busy); } skb_queue_purge(&sk->sk_receive_queue); @@ -1573,6 +1878,8 @@ static void l2cap_sock_init(struct sock *sk, struct sock *parent) chan->data = sk; chan->ops = &l2cap_chan_ops; + + l2cap_publish_rx_avail(chan); } static struct proto l2cap_proto = { @@ -1587,24 +1894,20 @@ static struct sock *l2cap_sock_alloc(struct net *net, struct socket *sock, struct sock *sk; struct l2cap_chan *chan; - sk = sk_alloc(net, PF_BLUETOOTH, prio, &l2cap_proto, kern); + sk = bt_sock_alloc(net, sock, &l2cap_proto, proto, prio, kern); if (!sk) return NULL; - sock_init_data(sock, sk); - INIT_LIST_HEAD(&bt_sk(sk)->accept_q); - sk->sk_destruct = l2cap_sock_destruct; sk->sk_sndtimeo = L2CAP_CONN_TIMEOUT; - sock_reset_flag(sk, SOCK_ZAPPED); - - sk->sk_protocol = proto; - sk->sk_state = BT_OPEN; + INIT_LIST_HEAD(&l2cap_pi(sk)->rx_busy); chan = l2cap_chan_create(); if (!chan) { sk_free(sk); + if (sock) + sock->sk = NULL; return NULL; } @@ -1655,6 +1958,7 @@ static const struct proto_ops l2cap_sock_ops = { .recvmsg = l2cap_sock_recvmsg, .poll = bt_sock_poll, .ioctl = bt_sock_ioctl, + .gettstamp = sock_gettstamp, .mmap = sock_no_mmap, .socketpair = sock_no_socketpair, .shutdown = l2cap_sock_shutdown, |
