This is a note to let you know that I've just added the patch titled
s390/zcrypt: fix zcard and zqueue hot-unplug memleak
to the 5.12-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:
s390-zcrypt-fix-zcard-and-zqueue-hot-unplug-memleak.patch
and it can be found in the queue-5.12 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From 70fac8088cfad9f3b379c9082832b4d7532c16c2 Mon Sep 17 00:00:00 2001
From: Harald Freudenberger <freude@xxxxxxxxxxxxx>
Date: Thu, 15 Apr 2021 11:22:03 +0200
Subject: s390/zcrypt: fix zcard and zqueue hot-unplug memleak
From: Harald Freudenberger <freude@xxxxxxxxxxxxx>
commit 70fac8088cfad9f3b379c9082832b4d7532c16c2 upstream.
Tests with kvm and a kmemdebug kernel showed, that on hot unplug the
zcard and zqueue structs for the unplugged card or queue are not
properly freed because of a mismatch with get/put for the embedded
kref counter.
This fix now adjusts the handling of the kref counters. With init the
kref counter starts with 1. This initial value needs to drop to zero
with the unregister of the card or queue to trigger the release and
free the object.
Fixes: 29c2680fd2bf ("s390/ap: fix ap devices reference counting")
Reported-by: Marc Hartmayer <mhartmay@xxxxxxxxxxxxx>
Signed-off-by: Harald Freudenberger <freude@xxxxxxxxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx
Reviewed-by: Julian Wiedmann <jwi@xxxxxxxxxxxxx>
Signed-off-by: Heiko Carstens <hca@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/s390/crypto/zcrypt_card.c | 1 +
drivers/s390/crypto/zcrypt_queue.c | 1 +
2 files changed, 2 insertions(+)
--- a/drivers/s390/crypto/zcrypt_card.c
+++ b/drivers/s390/crypto/zcrypt_card.c
@@ -192,5 +192,6 @@ void zcrypt_card_unregister(struct zcryp
spin_unlock(&zcrypt_list_lock);
sysfs_remove_group(&zc->card->ap_dev.device.kobj,
&zcrypt_card_attr_group);
+ zcrypt_card_put(zc);
}
EXPORT_SYMBOL(zcrypt_card_unregister);
--- a/drivers/s390/crypto/zcrypt_queue.c
+++ b/drivers/s390/crypto/zcrypt_queue.c
@@ -223,5 +223,6 @@ void zcrypt_queue_unregister(struct zcry
sysfs_remove_group(&zq->queue->ap_dev.device.kobj,
&zcrypt_queue_attr_group);
zcrypt_card_put(zc);
+ zcrypt_queue_put(zq);
}
EXPORT_SYMBOL(zcrypt_queue_unregister);
Patches currently in stable-queue which might be from freude@xxxxxxxxxxxxx are
queue-5.12/s390-zcrypt-fix-zcard-and-zqueue-hot-unplug-memleak.patch
