6.4-stable review patch. If anyone has any objections, please let me know.
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From: Luiz Augusto von Dentz luiz.von.dentz@intel.com
[ Upstream commit 5af1f84ed13a416297ab9ced7537f4d5ae7f329a ]
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 Stable-dep-of: 94d9ba9f9888 ("Bluetooth: hci_sync: Fix UAF in hci_disconnect_all_sync") Signed-off-by: Sasha Levin sashal@kernel.org --- net/bluetooth/hci_sync.c | 45 ++++++++++++++++++++++++++-------------- 1 file changed, 29 insertions(+), 16 deletions(-)
diff --git a/net/bluetooth/hci_sync.c b/net/bluetooth/hci_sync.c index ae5d5193d9ba7..60e213982635c 100644 --- a/net/bluetooth/hci_sync.c +++ b/net/bluetooth/hci_sync.c @@ -5337,27 +5337,20 @@ 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, reason); - /* 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) { - 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; case BT_OPEN: /* Cleanup bises that failed to be established */ if (test_and_clear_bit(HCI_CONN_BIG_SYNC_FAILED, &conn->flags)) { @@ -5368,10 +5361,30 @@ int hci_abort_conn_sync(struct hci_dev *hdev, struct hci_conn *conn, u8 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)