pps: add an error check in parport_attach

[ Upstream commit 62c5a01a5711c8e4be8ae7b6f0db663094615d48 ]

In parport_attach, the return value of ida_alloc is unchecked, witch leads
to the use of an invalid index value.

To address this issue, index should be checked. When the index value is
abnormal, the device should be freed.

Found by code review, compile tested only.

Cc: stable@vger.kernel.org
Fixes: fb56d97df70e ("pps: client: use new parport device model")
Signed-off-by: Ma Ke <make24@iscas.ac.cn>
Acked-by: Rodolfo Giometti <giometti@enneenne.com>
Link: https://lore.kernel.org/r/20240828131814.3034338-1-make24@iscas.ac.cn
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/drivers/pps/clients/pps_parport.c b/drivers/pps/clients/pps_parport.c
index 4bb3678c7e451721c4747e0852ed9606bebd178f..84e49204912f8505aa9b88e522e59b1a18227b1a 100644 (file)
--- a/drivers/pps/clients/pps_parport.c
+++ b/drivers/pps/clients/pps_parport.c
@@ -145,6 +145,9 @@ static void parport_attach(struct parport *port)
        }
 
        index = ida_alloc(&pps_client_index, GFP_KERNEL);
+       if (index < 0)
+               goto err_free_device;
+
        memset(&pps_client_cb, 0, sizeof(pps_client_cb));
        pps_client_cb.private = device;
        pps_client_cb.irq_func = parport_irq;
@@ -155,7 +158,7 @@ static void parport_attach(struct parport *port)
                                                    index);
        if (!device->pardev) {
                pr_err("couldn't register with %s\n", port->name);
-               goto err_free;
+               goto err_free_ida;
        }
 
        if (parport_claim_or_block(device->pardev) < 0) {
@@ -183,8 +186,9 @@ err_release_dev:
        parport_release(device->pardev);
 err_unregister_dev:
        parport_unregister_device(device->pardev);
-err_free:
+err_free_ida:
        ida_free(&pps_client_index, index);
+err_free_device:
        kfree(device);
 }