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authorLuiz Augusto von Dentz <luiz.von.dentz@intel.com>2022-12-07 03:34:42 +0300
committerLuiz Augusto von Dentz <luiz.von.dentz@intel.com>2022-12-13 01:19:26 +0300
commit241f51931c35085449502c10f64fb3ecd6e02171 (patch)
treead75682eb20f8b37e5ba8d1e737d4c6755c9f238 /net
parent0ba18967d4544955b2eff2fbc4f2a8750c4df90a (diff)
downloadlinux-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')
-rw-r--r--net/bluetooth/iso.c61
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);
}