From: Luiz Augusto von Dentz luiz.von.dentz@intel.com
[ Upstream commit 4d94f05558271654670d18c26c912da0c1c15549 ]
This reworks hci_cb_list to not use mutex hci_cb_list_lock to avoid bugs like the bellow:
BUG: sleeping function called from invalid context at kernel/locking/mutex.c:585 in_atomic(): 0, irqs_disabled(): 0, non_block: 0, pid: 5070, name: kworker/u9:2 preempt_count: 0, expected: 0 RCU nest depth: 1, expected: 0 4 locks held by kworker/u9:2/5070: #0: ffff888015be3948 ((wq_completion)hci0#2){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3229 [inline] #0: ffff888015be3948 ((wq_completion)hci0#2){+.+.}-{0:0}, at: process_scheduled_works+0x8e0/0x1770 kernel/workqueue.c:3335 #1: ffffc90003b6fd00 ((work_completion)(&hdev->rx_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3230 [inline] #1: ffffc90003b6fd00 ((work_completion)(&hdev->rx_work)){+.+.}-{0:0}, at: process_scheduled_works+0x91b/0x1770 kernel/workqueue.c:3335 #2: ffff8880665d0078 (&hdev->lock){+.+.}-{3:3}, at: hci_le_create_big_complete_evt+0xcf/0xae0 net/bluetooth/hci_event.c:6914 #3: ffffffff8e132020 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:298 [inline] #3: ffffffff8e132020 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:750 [inline] #3: ffffffff8e132020 (rcu_read_lock){....}-{1:2}, at: hci_le_create_big_complete_evt+0xdb/0xae0 net/bluetooth/hci_event.c:6915 CPU: 0 PID: 5070 Comm: kworker/u9:2 Not tainted 6.8.0-syzkaller-08073-g480e035fc4c7 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024 Workqueue: hci0 hci_rx_work Call Trace: <TASK> __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:114 __might_resched+0x5d4/0x780 kernel/sched/core.c:10187 __mutex_lock_common kernel/locking/mutex.c:585 [inline] __mutex_lock+0xc1/0xd70 kernel/locking/mutex.c:752 hci_connect_cfm include/net/bluetooth/hci_core.h:2004 [inline] hci_le_create_big_complete_evt+0x3d9/0xae0 net/bluetooth/hci_event.c:6939 hci_event_func net/bluetooth/hci_event.c:7514 [inline] hci_event_packet+0xa53/0x1540 net/bluetooth/hci_event.c:7569 hci_rx_work+0x3e8/0xca0 net/bluetooth/hci_core.c:4171 process_one_work kernel/workqueue.c:3254 [inline] process_scheduled_works+0xa00/0x1770 kernel/workqueue.c:3335 worker_thread+0x86d/0xd70 kernel/workqueue.c:3416 kthread+0x2f0/0x390 kernel/kthread.c:388 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:243 </TASK>
Reported-by: syzbot+2fb0835e0c9cefc34614@syzkaller.appspotmail.com Tested-by: syzbot+2fb0835e0c9cefc34614@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=2fb0835e0c9cefc34614 Signed-off-by: Luiz Augusto von Dentz luiz.von.dentz@intel.com Signed-off-by: Sasha Levin sashal@kernel.org --- include/net/bluetooth/hci_core.h | 108 ++++++++++++++++++++----------- net/bluetooth/hci_core.c | 10 +-- net/bluetooth/iso.c | 6 ++ net/bluetooth/l2cap_core.c | 12 ++-- net/bluetooth/rfcomm/core.c | 6 ++ net/bluetooth/sco.c | 12 ++-- 6 files changed, 97 insertions(+), 57 deletions(-)
diff --git a/include/net/bluetooth/hci_core.h b/include/net/bluetooth/hci_core.h index d26b57e87f7f..b37e95554271 100644 --- a/include/net/bluetooth/hci_core.h +++ b/include/net/bluetooth/hci_core.h @@ -815,7 +815,6 @@ struct hci_conn_params { extern struct list_head hci_dev_list; extern struct list_head hci_cb_list; extern rwlock_t hci_dev_list_lock; -extern struct mutex hci_cb_list_lock;
#define hci_dev_set_flag(hdev, nr) set_bit((nr), (hdev)->dev_flags) #define hci_dev_clear_flag(hdev, nr) clear_bit((nr), (hdev)->dev_flags) @@ -1769,24 +1768,47 @@ struct hci_cb {
char *name;
+ bool (*match) (struct hci_conn *conn); void (*connect_cfm) (struct hci_conn *conn, __u8 status); void (*disconn_cfm) (struct hci_conn *conn, __u8 status); void (*security_cfm) (struct hci_conn *conn, __u8 status, - __u8 encrypt); + __u8 encrypt); void (*key_change_cfm) (struct hci_conn *conn, __u8 status); void (*role_switch_cfm) (struct hci_conn *conn, __u8 status, __u8 role); };
+static inline void hci_cb_lookup(struct hci_conn *conn, struct list_head *list) +{ + struct hci_cb *cb, *cpy; + + rcu_read_lock(); + list_for_each_entry_rcu(cb, &hci_cb_list, list) { + if (cb->match && cb->match(conn)) { + cpy = kmalloc(sizeof(*cpy), GFP_ATOMIC); + if (!cpy) + break; + + *cpy = *cb; + INIT_LIST_HEAD(&cpy->list); + list_add_rcu(&cpy->list, list); + } + } + rcu_read_unlock(); +} + static inline void hci_connect_cfm(struct hci_conn *conn, __u8 status) { - struct hci_cb *cb; + struct list_head list; + struct hci_cb *cb, *tmp; + + INIT_LIST_HEAD(&list); + hci_cb_lookup(conn, &list);
- mutex_lock(&hci_cb_list_lock); - list_for_each_entry(cb, &hci_cb_list, list) { + list_for_each_entry_safe(cb, tmp, &list, list) { if (cb->connect_cfm) cb->connect_cfm(conn, status); + kfree(cb); } - mutex_unlock(&hci_cb_list_lock);
if (conn->connect_cfm_cb) conn->connect_cfm_cb(conn, status); @@ -1794,43 +1816,55 @@ static inline void hci_connect_cfm(struct hci_conn *conn, __u8 status)
static inline void hci_disconn_cfm(struct hci_conn *conn, __u8 reason) { - struct hci_cb *cb; + struct list_head list; + struct hci_cb *cb, *tmp; + + INIT_LIST_HEAD(&list); + hci_cb_lookup(conn, &list);
- mutex_lock(&hci_cb_list_lock); - list_for_each_entry(cb, &hci_cb_list, list) { + list_for_each_entry_safe(cb, tmp, &list, list) { if (cb->disconn_cfm) cb->disconn_cfm(conn, reason); + kfree(cb); } - mutex_unlock(&hci_cb_list_lock);
if (conn->disconn_cfm_cb) conn->disconn_cfm_cb(conn, reason); }
-static inline void hci_auth_cfm(struct hci_conn *conn, __u8 status) +static inline void hci_security_cfm(struct hci_conn *conn, __u8 status, + __u8 encrypt) { - struct hci_cb *cb; - __u8 encrypt; - - if (test_bit(HCI_CONN_ENCRYPT_PEND, &conn->flags)) - return; + struct list_head list; + struct hci_cb *cb, *tmp;
- encrypt = test_bit(HCI_CONN_ENCRYPT, &conn->flags) ? 0x01 : 0x00; + INIT_LIST_HEAD(&list); + hci_cb_lookup(conn, &list);
- mutex_lock(&hci_cb_list_lock); - list_for_each_entry(cb, &hci_cb_list, list) { + list_for_each_entry_safe(cb, tmp, &list, list) { if (cb->security_cfm) cb->security_cfm(conn, status, encrypt); + kfree(cb); } - mutex_unlock(&hci_cb_list_lock);
if (conn->security_cfm_cb) conn->security_cfm_cb(conn, status); }
+static inline void hci_auth_cfm(struct hci_conn *conn, __u8 status) +{ + __u8 encrypt; + + if (test_bit(HCI_CONN_ENCRYPT_PEND, &conn->flags)) + return; + + encrypt = test_bit(HCI_CONN_ENCRYPT, &conn->flags) ? 0x01 : 0x00; + + hci_security_cfm(conn, status, encrypt); +} + static inline void hci_encrypt_cfm(struct hci_conn *conn, __u8 status) { - struct hci_cb *cb; __u8 encrypt;
if (conn->state == BT_CONFIG) { @@ -1857,40 +1891,38 @@ static inline void hci_encrypt_cfm(struct hci_conn *conn, __u8 status) conn->sec_level = conn->pending_sec_level; }
- mutex_lock(&hci_cb_list_lock); - list_for_each_entry(cb, &hci_cb_list, list) { - if (cb->security_cfm) - cb->security_cfm(conn, status, encrypt); - } - mutex_unlock(&hci_cb_list_lock); - - if (conn->security_cfm_cb) - conn->security_cfm_cb(conn, status); + hci_security_cfm(conn, status, encrypt); }
static inline void hci_key_change_cfm(struct hci_conn *conn, __u8 status) { - struct hci_cb *cb; + struct list_head list; + struct hci_cb *cb, *tmp; + + INIT_LIST_HEAD(&list); + hci_cb_lookup(conn, &list);
- mutex_lock(&hci_cb_list_lock); - list_for_each_entry(cb, &hci_cb_list, list) { + list_for_each_entry_safe(cb, tmp, &list, list) { if (cb->key_change_cfm) cb->key_change_cfm(conn, status); + kfree(cb); } - mutex_unlock(&hci_cb_list_lock); }
static inline void hci_role_switch_cfm(struct hci_conn *conn, __u8 status, __u8 role) { - struct hci_cb *cb; + struct list_head list; + struct hci_cb *cb, *tmp; + + INIT_LIST_HEAD(&list); + hci_cb_lookup(conn, &list);
- mutex_lock(&hci_cb_list_lock); - list_for_each_entry(cb, &hci_cb_list, list) { + list_for_each_entry_safe(cb, tmp, &list, list) { if (cb->role_switch_cfm) cb->role_switch_cfm(conn, status, role); + kfree(cb); } - mutex_unlock(&hci_cb_list_lock); }
static inline bool hci_bdaddr_is_rpa(bdaddr_t *bdaddr, u8 addr_type) diff --git a/net/bluetooth/hci_core.c b/net/bluetooth/hci_core.c index 3cd7c212375f..496dac042b9c 100644 --- a/net/bluetooth/hci_core.c +++ b/net/bluetooth/hci_core.c @@ -58,7 +58,6 @@ DEFINE_RWLOCK(hci_dev_list_lock);
/* HCI callback list */ LIST_HEAD(hci_cb_list); -DEFINE_MUTEX(hci_cb_list_lock);
/* HCI ID Numbering */ static DEFINE_IDA(hci_index_ida); @@ -2978,9 +2977,7 @@ int hci_register_cb(struct hci_cb *cb) { BT_DBG("%p name %s", cb, cb->name);
- mutex_lock(&hci_cb_list_lock); - list_add_tail(&cb->list, &hci_cb_list); - mutex_unlock(&hci_cb_list_lock); + list_add_tail_rcu(&cb->list, &hci_cb_list);
return 0; } @@ -2990,9 +2987,8 @@ int hci_unregister_cb(struct hci_cb *cb) { BT_DBG("%p name %s", cb, cb->name);
- mutex_lock(&hci_cb_list_lock); - list_del(&cb->list); - mutex_unlock(&hci_cb_list_lock); + list_del_rcu(&cb->list); + synchronize_rcu();
return 0; } diff --git a/net/bluetooth/iso.c b/net/bluetooth/iso.c index ff15d5192768..45dc39aa7618 100644 --- a/net/bluetooth/iso.c +++ b/net/bluetooth/iso.c @@ -1575,6 +1575,11 @@ int iso_connect_ind(struct hci_dev *hdev, bdaddr_t *bdaddr, __u8 *flags) return lm; }
+static bool iso_match(struct hci_conn *hcon) +{ + return hcon->type == ISO_LINK || hcon->type == LE_LINK; +} + static void iso_connect_cfm(struct hci_conn *hcon, __u8 status) { if (hcon->type != ISO_LINK) { @@ -1744,6 +1749,7 @@ void iso_recv(struct hci_conn *hcon, struct sk_buff *skb, u16 flags)
static struct hci_cb iso_cb = { .name = "ISO", + .match = iso_match, .connect_cfm = iso_connect_cfm, .disconn_cfm = iso_disconn_cfm, }; diff --git a/net/bluetooth/l2cap_core.c b/net/bluetooth/l2cap_core.c index 187c91843876..2a8051fae08c 100644 --- a/net/bluetooth/l2cap_core.c +++ b/net/bluetooth/l2cap_core.c @@ -8273,6 +8273,11 @@ static struct l2cap_chan *l2cap_global_fixed_chan(struct l2cap_chan *c, return NULL; }
+static bool l2cap_match(struct hci_conn *hcon) +{ + return hcon->type == ACL_LINK || hcon->type == LE_LINK; +} + static void l2cap_connect_cfm(struct hci_conn *hcon, u8 status) { struct hci_dev *hdev = hcon->hdev; @@ -8280,9 +8285,6 @@ static void l2cap_connect_cfm(struct hci_conn *hcon, u8 status) struct l2cap_chan *pchan; u8 dst_type;
- if (hcon->type != ACL_LINK && hcon->type != LE_LINK) - return; - BT_DBG("hcon %p bdaddr %pMR status %d", hcon, &hcon->dst, status);
if (status) { @@ -8347,9 +8349,6 @@ int l2cap_disconn_ind(struct hci_conn *hcon)
static void l2cap_disconn_cfm(struct hci_conn *hcon, u8 reason) { - if (hcon->type != ACL_LINK && hcon->type != LE_LINK) - return; - BT_DBG("hcon %p reason %d", hcon, reason);
l2cap_conn_del(hcon, bt_to_errno(reason)); @@ -8637,6 +8636,7 @@ void l2cap_recv_acldata(struct hci_conn *hcon, struct sk_buff *skb, u16 flags)
static struct hci_cb l2cap_cb = { .name = "L2CAP", + .match = l2cap_match, .connect_cfm = l2cap_connect_cfm, .disconn_cfm = l2cap_disconn_cfm, .security_cfm = l2cap_security_cfm, diff --git a/net/bluetooth/rfcomm/core.c b/net/bluetooth/rfcomm/core.c index 4f54c7df3a94..1686fa60e278 100644 --- a/net/bluetooth/rfcomm/core.c +++ b/net/bluetooth/rfcomm/core.c @@ -2130,6 +2130,11 @@ static int rfcomm_run(void *unused) return 0; }
+static bool rfcomm_match(struct hci_conn *hcon) +{ + return hcon->type == ACL_LINK; +} + static void rfcomm_security_cfm(struct hci_conn *conn, u8 status, u8 encrypt) { struct rfcomm_session *s; @@ -2176,6 +2181,7 @@ static void rfcomm_security_cfm(struct hci_conn *conn, u8 status, u8 encrypt)
static struct hci_cb rfcomm_cb = { .name = "RFCOMM", + .match = rfcomm_match, .security_cfm = rfcomm_security_cfm };
diff --git a/net/bluetooth/sco.c b/net/bluetooth/sco.c index ad5afde17213..d62019e575a7 100644 --- a/net/bluetooth/sco.c +++ b/net/bluetooth/sco.c @@ -1366,11 +1366,13 @@ int sco_connect_ind(struct hci_dev *hdev, bdaddr_t *bdaddr, __u8 *flags) return lm; }
-static void sco_connect_cfm(struct hci_conn *hcon, __u8 status) +static bool sco_match(struct hci_conn *hcon) { - if (hcon->type != SCO_LINK && hcon->type != ESCO_LINK) - return; + return hcon->type == SCO_LINK || hcon->type == ESCO_LINK; +}
+static void sco_connect_cfm(struct hci_conn *hcon, __u8 status) +{ BT_DBG("hcon %p bdaddr %pMR status %u", hcon, &hcon->dst, status);
if (!status) { @@ -1385,9 +1387,6 @@ static void sco_connect_cfm(struct hci_conn *hcon, __u8 status)
static void sco_disconn_cfm(struct hci_conn *hcon, __u8 reason) { - if (hcon->type != SCO_LINK && hcon->type != ESCO_LINK) - return; - BT_DBG("hcon %p reason %d", hcon, reason);
sco_conn_del(hcon, bt_to_errno(reason)); @@ -1413,6 +1412,7 @@ void sco_recv_scodata(struct hci_conn *hcon, struct sk_buff *skb)
static struct hci_cb sco_cb = { .name = "SCO", + .match = sco_match, .connect_cfm = sco_connect_cfm, .disconn_cfm = sco_disconn_cfm, };