diff options
author | Luiz Augusto von Dentz <luiz.von.dentz@intel.com> | 2022-12-07 03:34:42 +0300 |
---|---|---|
committer | Luiz Augusto von Dentz <luiz.von.dentz@intel.com> | 2022-12-13 01:19:26 +0300 |
commit | 241f51931c35085449502c10f64fb3ecd6e02171 (patch) | |
tree | ad75682eb20f8b37e5ba8d1e737d4c6755c9f238 /net/bluetooth/iso.c | |
parent | 0ba18967d4544955b2eff2fbc4f2a8750c4df90a (diff) | |
download | linux-241f51931c35085449502c10f64fb3ecd6e02171.tar.xz |
Bluetooth: ISO: Avoid circular locking dependency
This attempts to avoid circular locking dependency between sock_lock
and hdev_lock:
WARNING: possible circular locking dependency detected
6.0.0-rc7-03728-g18dd8ab0a783 #3 Not tainted
------------------------------------------------------
kworker/u3:2/53 is trying to acquire lock:
ffff888000254130 (sk_lock-AF_BLUETOOTH-BTPROTO_ISO){+.+.}-{0:0}, at:
iso_conn_del+0xbd/0x1d0
but task is already holding lock:
ffffffff9f39a080 (hci_cb_list_lock){+.+.}-{3:3}, at:
hci_le_cis_estabilished_evt+0x1b5/0x500
which lock already depends on the new lock.
the existing dependency chain (in reverse order) is:
-> #2 (hci_cb_list_lock){+.+.}-{3:3}:
__mutex_lock+0x10e/0xfe0
hci_le_remote_feat_complete_evt+0x17f/0x320
hci_event_packet+0x39c/0x7d0
hci_rx_work+0x2bf/0x950
process_one_work+0x569/0x980
worker_thread+0x2a3/0x6f0
kthread+0x153/0x180
ret_from_fork+0x22/0x30
-> #1 (&hdev->lock){+.+.}-{3:3}:
__mutex_lock+0x10e/0xfe0
iso_connect_cis+0x6f/0x5a0
iso_sock_connect+0x1af/0x710
__sys_connect+0x17e/0x1b0
__x64_sys_connect+0x37/0x50
do_syscall_64+0x43/0x90
entry_SYSCALL_64_after_hwframe+0x62/0xcc
-> #0 (sk_lock-AF_BLUETOOTH-BTPROTO_ISO){+.+.}-{0:0}:
__lock_acquire+0x1b51/0x33d0
lock_acquire+0x16f/0x3b0
lock_sock_nested+0x32/0x80
iso_conn_del+0xbd/0x1d0
iso_connect_cfm+0x226/0x680
hci_le_cis_estabilished_evt+0x1ed/0x500
hci_event_packet+0x39c/0x7d0
hci_rx_work+0x2bf/0x950
process_one_work+0x569/0x980
worker_thread+0x2a3/0x6f0
kthread+0x153/0x180
ret_from_fork+0x22/0x30
other info that might help us debug this:
Chain exists of:
sk_lock-AF_BLUETOOTH-BTPROTO_ISO --> &hdev->lock --> hci_cb_list_lock
Possible unsafe locking scenario:
CPU0 CPU1
---- ----
lock(hci_cb_list_lock);
lock(&hdev->lock);
lock(hci_cb_list_lock);
lock(sk_lock-AF_BLUETOOTH-BTPROTO_ISO);
*** DEADLOCK ***
4 locks held by kworker/u3:2/53:
#0: ffff8880021d9130 ((wq_completion)hci0#2){+.+.}-{0:0}, at:
process_one_work+0x4ad/0x980
#1: ffff888002387de0 ((work_completion)(&hdev->rx_work)){+.+.}-{0:0},
at: process_one_work+0x4ad/0x980
#2: ffff888001ac0070 (&hdev->lock){+.+.}-{3:3}, at:
hci_le_cis_estabilished_evt+0xc3/0x500
#3: ffffffff9f39a080 (hci_cb_list_lock){+.+.}-{3:3}, at:
hci_le_cis_estabilished_evt+0x1b5/0x500
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Diffstat (limited to 'net/bluetooth/iso.c')
-rw-r--r-- | net/bluetooth/iso.c | 61 |
1 files changed, 38 insertions, 23 deletions
diff --git a/net/bluetooth/iso.c b/net/bluetooth/iso.c index e23aabf4e0cf..035bb5d25f85 100644 --- a/net/bluetooth/iso.c +++ b/net/bluetooth/iso.c @@ -261,13 +261,13 @@ static int iso_connect_bis(struct sock *sk) if (!bis_capable(hdev)) { err = -EOPNOTSUPP; - goto done; + goto unlock; } /* Fail if out PHYs are marked as disabled */ if (!iso_pi(sk)->qos.out.phy) { err = -EINVAL; - goto done; + goto unlock; } hcon = hci_connect_bis(hdev, &iso_pi(sk)->dst, @@ -276,22 +276,27 @@ static int iso_connect_bis(struct sock *sk) iso_pi(sk)->base); if (IS_ERR(hcon)) { err = PTR_ERR(hcon); - goto done; + goto unlock; } conn = iso_conn_add(hcon); if (!conn) { hci_conn_drop(hcon); err = -ENOMEM; - goto done; + goto unlock; } + hci_dev_unlock(hdev); + hci_dev_put(hdev); + + lock_sock(sk); + /* Update source addr of the socket */ bacpy(&iso_pi(sk)->src, &hcon->src); err = iso_chan_add(conn, sk, NULL); if (err) - goto done; + goto release; if (hcon->state == BT_CONNECTED) { iso_sock_clear_timer(sk); @@ -301,7 +306,11 @@ static int iso_connect_bis(struct sock *sk) iso_sock_set_timer(sk, sk->sk_sndtimeo); } -done: +release: + release_sock(sk); + return err; + +unlock: hci_dev_unlock(hdev); hci_dev_put(hdev); return err; @@ -325,13 +334,13 @@ static int iso_connect_cis(struct sock *sk) if (!cis_central_capable(hdev)) { err = -EOPNOTSUPP; - goto done; + goto unlock; } /* Fail if either PHYs are marked as disabled */ if (!iso_pi(sk)->qos.in.phy && !iso_pi(sk)->qos.out.phy) { err = -EINVAL; - goto done; + goto unlock; } /* Just bind if DEFER_SETUP has been set */ @@ -341,7 +350,7 @@ static int iso_connect_cis(struct sock *sk) &iso_pi(sk)->qos); if (IS_ERR(hcon)) { err = PTR_ERR(hcon); - goto done; + goto unlock; } } else { hcon = hci_connect_cis(hdev, &iso_pi(sk)->dst, @@ -349,7 +358,7 @@ static int iso_connect_cis(struct sock *sk) &iso_pi(sk)->qos); if (IS_ERR(hcon)) { err = PTR_ERR(hcon); - goto done; + goto unlock; } } @@ -357,15 +366,20 @@ static int iso_connect_cis(struct sock *sk) if (!conn) { hci_conn_drop(hcon); err = -ENOMEM; - goto done; + goto unlock; } + hci_dev_unlock(hdev); + hci_dev_put(hdev); + + lock_sock(sk); + /* Update source addr of the socket */ bacpy(&iso_pi(sk)->src, &hcon->src); err = iso_chan_add(conn, sk, NULL); if (err) - goto done; + goto release; if (hcon->state == BT_CONNECTED) { iso_sock_clear_timer(sk); @@ -378,7 +392,11 @@ static int iso_connect_cis(struct sock *sk) iso_sock_set_timer(sk, sk->sk_sndtimeo); } -done: +release: + release_sock(sk); + return err; + +unlock: hci_dev_unlock(hdev); hci_dev_put(hdev); return err; @@ -832,20 +850,23 @@ static int iso_sock_connect(struct socket *sock, struct sockaddr *addr, bacpy(&iso_pi(sk)->dst, &sa->iso_bdaddr); iso_pi(sk)->dst_type = sa->iso_bdaddr_type; + release_sock(sk); + if (bacmp(&iso_pi(sk)->dst, BDADDR_ANY)) err = iso_connect_cis(sk); else err = iso_connect_bis(sk); if (err) - goto done; + return err; + + lock_sock(sk); if (!test_bit(BT_SK_DEFER_SETUP, &bt_sk(sk)->flags)) { err = bt_sock_wait_state(sk, BT_CONNECTED, sock_sndtimeo(sk, flags & O_NONBLOCK)); } -done: release_sock(sk); return err; } @@ -1101,28 +1122,22 @@ static int iso_sock_recvmsg(struct socket *sock, struct msghdr *msg, { struct sock *sk = sock->sk; struct iso_pinfo *pi = iso_pi(sk); - int err; BT_DBG("sk %p", sk); - lock_sock(sk); - if (test_and_clear_bit(BT_SK_DEFER_SETUP, &bt_sk(sk)->flags)) { switch (sk->sk_state) { case BT_CONNECT2: + lock_sock(sk); iso_conn_defer_accept(pi->conn->hcon); sk->sk_state = BT_CONFIG; release_sock(sk); return 0; case BT_CONNECT: - err = iso_connect_cis(sk); - release_sock(sk); - return err; + return iso_connect_cis(sk); } } - release_sock(sk); - return bt_sock_recvmsg(sock, msg, len, flags); } |