Patch "pps: add an error check in parport_attach" has been added to the 5.4-stable tree

[Sasha Levin <sashal@xxxxxxxxxx>]

This is a note to let you know that I've just added the patch titled

    pps: add an error check in parport_attach

to the 5.4-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     pps-add-an-error-check-in-parport_attach.patch
and it can be found in the queue-5.4 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.



commit 55a0aa62eba90973cdd0ef048db3143695cd07f7
Author: Ma Ke <make24@xxxxxxxxxxx>
Date:   Wed Aug 28 21:18:14 2024 +0800

    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@xxxxxxxxxxxxxxx
    Fixes: fb56d97df70e ("pps: client: use new parport device model")
    Signed-off-by: Ma Ke <make24@xxxxxxxxxxx>
    Acked-by: Rodolfo Giometti <giometti@xxxxxxxxxxxx>
    Link: https://lore.kernel.org/r/20240828131814.3034338-1-make24@xxxxxxxxxxx
    Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
    Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>

diff --git a/drivers/pps/clients/pps_parport.c b/drivers/pps/clients/pps_parport.c
index 4bb3678c7e451..84e49204912f8 100644
--- 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 @@ static void parport_attach(struct parport *port)
 	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);
 }