Bluetooth: hci_sync: Fix overwriting request callback

In a few cases the stack may generate commands as responses to events
which would happen to overwrite the sent_cmd, so this attempts to store
the request in req_skb so even if sent_cmd is replaced with a new
command the pending request will remain in stored in req_skb.

Fixes: 6a98e3836f ("Bluetooth: Add helper for serialized HCI command execution")
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
This commit is contained in:
Luiz Augusto von Dentz 2024-02-16 16:20:11 -05:00
parent 22cbf4f84c
commit 2615fd9a7c
5 changed files with 61 additions and 27 deletions

View File

@ -552,6 +552,7 @@ struct hci_dev {
__u32 req_status;
__u32 req_result;
struct sk_buff *req_skb;
struct sk_buff *req_rsp;
void *smp_data;
void *smp_bredr_data;

View File

@ -2918,7 +2918,7 @@ int hci_abort_conn(struct hci_conn *conn, u8 reason)
case HCI_EV_LE_CONN_COMPLETE:
case HCI_EV_LE_ENHANCED_CONN_COMPLETE:
case HCI_EVT_LE_CIS_ESTABLISHED:
hci_cmd_sync_cancel(hdev, -ECANCELED);
hci_cmd_sync_cancel(hdev, ECANCELED);
break;
}
/* Cancel connect attempt if still queued/pending */

View File

@ -1522,8 +1522,8 @@ static void hci_cmd_timeout(struct work_struct *work)
struct hci_dev *hdev = container_of(work, struct hci_dev,
cmd_timer.work);
if (hdev->sent_cmd) {
u16 opcode = hci_skb_opcode(hdev->sent_cmd);
if (hdev->req_skb) {
u16 opcode = hci_skb_opcode(hdev->req_skb);
bt_dev_err(hdev, "command 0x%4.4x tx timeout", opcode);
@ -2828,6 +2828,7 @@ void hci_release_dev(struct hci_dev *hdev)
ida_destroy(&hdev->unset_handle_ida);
ida_free(&hci_index_ida, hdev->id);
kfree_skb(hdev->sent_cmd);
kfree_skb(hdev->req_skb);
kfree_skb(hdev->recv_event);
kfree(hdev);
}
@ -3157,21 +3158,33 @@ int __hci_cmd_send(struct hci_dev *hdev, u16 opcode, u32 plen,
EXPORT_SYMBOL(__hci_cmd_send);
/* Get data from the previously sent command */
void *hci_sent_cmd_data(struct hci_dev *hdev, __u16 opcode)
static void *hci_cmd_data(struct sk_buff *skb, __u16 opcode)
{
struct hci_command_hdr *hdr;
if (!hdev->sent_cmd)
if (!skb || skb->len < HCI_COMMAND_HDR_SIZE)
return NULL;
hdr = (void *) hdev->sent_cmd->data;
hdr = (void *)skb->data;
if (hdr->opcode != cpu_to_le16(opcode))
return NULL;
BT_DBG("%s opcode 0x%4.4x", hdev->name, opcode);
return skb->data + HCI_COMMAND_HDR_SIZE;
}
return hdev->sent_cmd->data + HCI_COMMAND_HDR_SIZE;
/* Get data from the previously sent command */
void *hci_sent_cmd_data(struct hci_dev *hdev, __u16 opcode)
{
void *data;
/* Check if opcode matches last sent command */
data = hci_cmd_data(hdev->sent_cmd, opcode);
if (!data)
/* Check if opcode matches last request */
data = hci_cmd_data(hdev->req_skb, opcode);
return data;
}
/* Get data from last received event */
@ -4072,17 +4085,19 @@ void hci_req_cmd_complete(struct hci_dev *hdev, u16 opcode, u8 status,
if (!status && !hci_req_is_complete(hdev))
return;
skb = hdev->req_skb;
/* If this was the last command in a request the complete
* callback would be found in hdev->sent_cmd instead of the
* callback would be found in hdev->req_skb instead of the
* command queue (hdev->cmd_q).
*/
if (bt_cb(hdev->sent_cmd)->hci.req_flags & HCI_REQ_SKB) {
*req_complete_skb = bt_cb(hdev->sent_cmd)->hci.req_complete_skb;
if (skb && bt_cb(skb)->hci.req_flags & HCI_REQ_SKB) {
*req_complete_skb = bt_cb(skb)->hci.req_complete_skb;
return;
}
if (bt_cb(hdev->sent_cmd)->hci.req_complete) {
*req_complete = bt_cb(hdev->sent_cmd)->hci.req_complete;
if (skb && bt_cb(skb)->hci.req_complete) {
*req_complete = bt_cb(skb)->hci.req_complete;
return;
}
@ -4199,8 +4214,11 @@ static void hci_send_cmd_sync(struct hci_dev *hdev, struct sk_buff *skb)
return;
}
if (hci_req_status_pend(hdev))
hci_dev_set_flag(hdev, HCI_CMD_PENDING);
if (hci_req_status_pend(hdev) &&
!hci_dev_test_and_set_flag(hdev, HCI_CMD_PENDING)) {
kfree_skb(hdev->req_skb);
hdev->req_skb = skb_clone(skb, GFP_KERNEL);
}
atomic_dec(&hdev->cmd_cnt);
}

View File

@ -4368,7 +4368,7 @@ static void hci_cmd_status_evt(struct hci_dev *hdev, void *data,
* (since for this kind of commands there will not be a command
* complete event).
*/
if (ev->status || (hdev->sent_cmd && !hci_skb_event(hdev->sent_cmd))) {
if (ev->status || (hdev->req_skb && !hci_skb_event(hdev->req_skb))) {
hci_req_cmd_complete(hdev, *opcode, ev->status, req_complete,
req_complete_skb);
if (hci_dev_test_flag(hdev, HCI_CMD_PENDING)) {
@ -7170,10 +7170,10 @@ static void hci_le_meta_evt(struct hci_dev *hdev, void *data,
bt_dev_dbg(hdev, "subevent 0x%2.2x", ev->subevent);
/* Only match event if command OGF is for LE */
if (hdev->sent_cmd &&
hci_opcode_ogf(hci_skb_opcode(hdev->sent_cmd)) == 0x08 &&
hci_skb_event(hdev->sent_cmd) == ev->subevent) {
*opcode = hci_skb_opcode(hdev->sent_cmd);
if (hdev->req_skb &&
hci_opcode_ogf(hci_skb_opcode(hdev->req_skb)) == 0x08 &&
hci_skb_event(hdev->req_skb) == ev->subevent) {
*opcode = hci_skb_opcode(hdev->req_skb);
hci_req_cmd_complete(hdev, *opcode, 0x00, req_complete,
req_complete_skb);
}
@ -7541,10 +7541,10 @@ void hci_event_packet(struct hci_dev *hdev, struct sk_buff *skb)
}
/* Only match event if command OGF is not for LE */
if (hdev->sent_cmd &&
hci_opcode_ogf(hci_skb_opcode(hdev->sent_cmd)) != 0x08 &&
hci_skb_event(hdev->sent_cmd) == event) {
hci_req_cmd_complete(hdev, hci_skb_opcode(hdev->sent_cmd),
if (hdev->req_skb &&
hci_opcode_ogf(hci_skb_opcode(hdev->req_skb)) != 0x08 &&
hci_skb_event(hdev->req_skb) == event) {
hci_req_cmd_complete(hdev, hci_skb_opcode(hdev->req_skb),
status, &req_complete, &req_complete_skb);
req_evt = event;
}

View File

@ -32,6 +32,10 @@ static void hci_cmd_sync_complete(struct hci_dev *hdev, u8 result, u16 opcode,
hdev->req_result = result;
hdev->req_status = HCI_REQ_DONE;
/* Free the request command so it is not used as response */
kfree_skb(hdev->req_skb);
hdev->req_skb = NULL;
if (skb) {
struct sock *sk = hci_skb_sk(skb);
@ -39,7 +43,7 @@ static void hci_cmd_sync_complete(struct hci_dev *hdev, u8 result, u16 opcode,
if (sk)
sock_put(sk);
hdev->req_skb = skb_get(skb);
hdev->req_rsp = skb_get(skb);
}
wake_up_interruptible(&hdev->req_wait_q);
@ -187,8 +191,8 @@ struct sk_buff *__hci_cmd_sync_sk(struct hci_dev *hdev, u16 opcode, u32 plen,
hdev->req_status = 0;
hdev->req_result = 0;
skb = hdev->req_skb;
hdev->req_skb = NULL;
skb = hdev->req_rsp;
hdev->req_rsp = NULL;
bt_dev_dbg(hdev, "end: err %d", err);
@ -5021,6 +5025,11 @@ int hci_dev_open_sync(struct hci_dev *hdev)
hdev->sent_cmd = NULL;
}
if (hdev->req_skb) {
kfree_skb(hdev->req_skb);
hdev->req_skb = NULL;
}
clear_bit(HCI_RUNNING, &hdev->flags);
hci_sock_dev_event(hdev, HCI_DEV_CLOSE);
@ -5181,6 +5190,12 @@ int hci_dev_close_sync(struct hci_dev *hdev)
hdev->sent_cmd = NULL;
}
/* Drop last request */
if (hdev->req_skb) {
kfree_skb(hdev->req_skb);
hdev->req_skb = NULL;
}
clear_bit(HCI_RUNNING, &hdev->flags);
hci_sock_dev_event(hdev, HCI_DEV_CLOSE);