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| author | Stepan Ionichev <sozdayvek@gmail.com> | 2026-05-14 19:37:45 +0500 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2026-06-27 11:07:41 +0100 |
| commit | d72650a4f334581b23a1892b888a4cb1be142f76 (patch) | |
| tree | d0245b4640442e2cef6ed5fc0c316cc34f2f0424 | |
| parent | ead244f937d6ee50600f974b6a3a7374d74784a6 (diff) | |
| download | linux-stable-d72650a4f334581b23a1892b888a4cb1be142f76.tar.gz linux-stable-d72650a4f334581b23a1892b888a4cb1be142f76.zip | |
serial: 8250_dw: unregister 8250 port if clk_notifier_register() fails
commit 10fc708b4de7f86002d2d735a2dbf3b5b7f65692 upstream.
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>
| -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 2af0c4d0ad82..035b46e13666 100644 --- a/drivers/tty/serial/8250/8250_dw.c +++ b/drivers/tty/serial/8250/8250_dw.c @@ -850,8 +850,10 @@ 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_dfl_wq, &data->clk_work); } |