diff options
| author | Stepan Ionichev <sozdayvek@gmail.com> | 2026-06-25 09:49:39 -0400 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2026-07-04 13:43:36 +0200 |
| commit | 07ffe414a708ae60551401cec5d727ed156b8caf (patch) | |
| tree | c21b370a794875cb759027e36348246b80e549dc | |
| parent | d5c81a095c86fe507c032d08f3a8cfc518444927 (diff) | |
| download | linux-07ffe414a708ae60551401cec5d727ed156b8caf.tar.gz linux-07ffe414a708ae60551401cec5d727ed156b8caf.zip | |
serial: 8250_dw: unregister 8250 port if clk_notifier_register() fails
[ Upstream commit 10fc708b4de7f86002d2d735a2dbf3b5b7f65692 ]
dw8250_probe() registers the 8250 port via serial8250_register_8250_port()
and then, if the device has a clock, registers a clock notifier. If
clk_notifier_register() fails, probe returns the error but leaves the
8250 port registered. The matching serial8250_unregister_port() lives
in dw8250_remove(), which is not called when probe fails, so the port
slot stays occupied until the device is rebound or the system is
rebooted. The devm-allocated driver data is freed while the port still
references it (via the saved private_data and serial_in/serial_out
callbacks), so any access to that port slot before a rebind is a
use-after-free hazard.
Unregister the port on the clk_notifier_register() error path.
Fixes: cc816969d7b5 ("serial: 8250_dw: Fix common clocks usage race condition")
Cc: stable@vger.kernel.org
Signed-off-by: Stepan Ionichev <sozdayvek@gmail.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://patch.msgid.link/20260514143746.23671-2-sozdayvek@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | drivers/tty/serial/8250/8250_dw.c | 4 |
1 files changed, 3 insertions, 1 deletions
diff --git a/drivers/tty/serial/8250/8250_dw.c b/drivers/tty/serial/8250/8250_dw.c index f17dc3de020c..7b2e72bfeb75 100644 --- a/drivers/tty/serial/8250/8250_dw.c +++ b/drivers/tty/serial/8250/8250_dw.c @@ -655,8 +655,10 @@ static int dw8250_probe(struct platform_device *pdev) */ if (data->clk) { err = clk_notifier_register(data->clk, &data->clk_notifier); - if (err) + if (err) { + serial8250_unregister_port(data->data.line); return dev_err_probe(dev, err, "Failed to set the clock notifier\n"); + } queue_work(system_unbound_wq, &data->clk_work); } |