commit 5af1f84ed13a416297ab9ced7537f4d5ae7f329a upstream.

Connections may be cleanup while waiting for the commands to complete so this attempts to check if the connection handle remains valid in case of errors that would lead to call hci_conn_failed:

BUG: KASAN: slab-use-after-free in hci_conn_failed+0x1f/0x160 Read of size 8 at addr ffff888001376958 by task kworker/u3:0/52

CPU: 0 PID: 52 Comm: kworker/u3:0 Not tainted 6.5.0-rc1-00527-g2dfe76d58d3a #5615 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-1.fc38 04/01/2014 Workqueue: hci0 hci_cmd_sync_work Call Trace: <TASK> dump_stack_lvl+0x1d/0x70 print_report+0xce/0x620 ? __virt_addr_valid+0xd4/0x150 ? hci_conn_failed+0x1f/0x160 kasan_report+0xd1/0x100 ? hci_conn_failed+0x1f/0x160 hci_conn_failed+0x1f/0x160 hci_abort_conn_sync+0x237/0x360

Signed-off-by: Luiz Augusto von Dentz luiz.von.dentz@intel.com Signed-off-by: Sumanth Gavini sumanth.gavini@yahoo.com --- net/bluetooth/hci_sync.c | 43 +++++++++++++++++++++++++++------------- 1 file changed, 29 insertions(+), 14 deletions(-)

diff --git a/net/bluetooth/hci_sync.c b/net/bluetooth/hci_sync.c index 3f905ee4338f..acff47da799a 100644 --- a/net/bluetooth/hci_sync.c +++ b/net/bluetooth/hci_sync.c @@ -5525,31 +5525,46 @@ static int hci_reject_conn_sync(struct hci_dev *hdev, struct hci_conn *conn,

int hci_abort_conn_sync(struct hci_dev *hdev, struct hci_conn *conn, u8 reason) { - int err; + int err = 0; + u16 handle = conn->handle;

switch (conn->state) { case BT_CONNECTED: case BT_CONFIG: - return hci_disconnect_sync(hdev, conn, reason); + err = hci_disconnect_sync(hdev, conn, reason); + break; case BT_CONNECT: err = hci_connect_cancel_sync(hdev, conn); - /* Cleanup hci_conn object if it cannot be cancelled as it - * likelly means the controller and host stack are out of sync. - */ - if (err) { - hci_dev_lock(hdev); - hci_conn_failed(conn, err); - hci_dev_unlock(hdev); - } - return err; + break; case BT_CONNECT2: - return hci_reject_conn_sync(hdev, conn, reason); + err = hci_reject_conn_sync(hdev, conn, reason); + break; default: conn->state = BT_CLOSED; - break; + return 0; }

- return 0; + /* Cleanup hci_conn object if it cannot be cancelled as it + * likelly means the controller and host stack are out of sync + * or in case of LE it was still scanning so it can be cleanup + * safely. + */ + if (err) { + struct hci_conn *c; + + /* Check if the connection hasn't been cleanup while waiting + * commands to complete. + */ + c = hci_conn_hash_lookup_handle(hdev, handle); + if (!c || c != conn) + return 0; + + hci_dev_lock(hdev); + hci_conn_failed(conn, err); + hci_dev_unlock(hdev); + } + + return err; }

static int hci_disconnect_all_sync(struct hci_dev *hdev, u8 reason)