From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id BDB6946EC84; Tue, 21 Jul 2026 17:56:03 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784656565; cv=none; b=nhpChOrT+slOvnGV8Rn7NCl8r02oL4gSGmMxcFQLM+emvGgbP9vK7ELu1aBJmwBY6wHhwKT/JdRsnxZQ+aSN15c01DzAkox9KCL7F7ZBPtUoZTa3HCk5IxyS04irZUHVROORYAqZREfOXK7E0IdRYLhSvWe+qosbA2fXID1qRV4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784656565; c=relaxed/simple; bh=zrGdwm3wQrkbZXPTdRE0Ij1YzesobEA90/yYGcUs8s0=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=BEfcbh/QH9ik+Pj/zCm8w43+HOmN1ZqiW0GFadcMHcXhC78u6qksbcVJwNUMoPPg1cZ6ZoQIQC0Rq6wwl9RiKvMmWNUeMlpMHkbPcRlbhjwR5OMw1bKHvJFfWR1SEyzPtKk43WrOT0XtMu3KURjIltys8hQEq9xF16obwrE3+Zg= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=BCyz9phM; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="BCyz9phM" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 57B681F000E9; Tue, 21 Jul 2026 17:56:03 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1784656563; bh=ZabjluDp055JdDJR96E7f7t3437vkxIfR5ZE1os1AYs=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=BCyz9phM9Zt8DzpwO3TWGOnorYQXKgikhHyQQekY2npgGcbjRpaufIfh42LjIWnjq sHpO9gqEiaEGmLP1ScbAhtYM0MtrTU9sh7jVjnjrVwy8Op9Dx7LOdzLehUVyPcm5Q6 VjWtabsg5SAqhhWWM8of6h+pFNjw6x4IS9JzEdXE= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Jia Jia , Peter Hilber , "Michael S. Tsirkin" , Sasha Levin Subject: [PATCH 6.18 0436/1611] virtio: rtc: tear down old virtqueues before restore Date: Tue, 21 Jul 2026 17:09:12 +0200 Message-ID: <20260721152525.091743595@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260721152514.750365251@linuxfoundation.org> References: <20260721152514.750365251@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Jia Jia [ Upstream commit 548d2208455f14e6121404c6e30e997bfe0cd264 ] virtio_device_restore() resets the device and restores the negotiated features before calling ->restore(). viortc_freeze() intentionally leaves the existing virtqueues in place so the alarm queue can still wake the system, but viortc_restore() immediately calls viortc_init_vqs() without first deleting those old queues. If virtqueue reinitialization fails on virtio-pci, the transport error path can run vp_del_vqs() against a newly allocated vp_dev->vqs array while vdev->vqs still contains the old virtqueues. vp_del_vqs() then looks up queue state through the new array and can dereference a NULL info pointer in vp_del_vq(), crashing the guest kernel during restore. This can also happen during a non-faulty reinitialization, when one of the vp_find_vqs_msix() attempts is unsuccessful before a later attempt would succeed. Delete the stale virtqueues before rebuilding them. If restore fails before virtio_device_ready(), reuse the remove path to stop the device. Once the device is ready, return errors directly instead of deleting the virtqueues again. Fixes: 0623c7592768 ("virtio_rtc: Add module and driver core") Signed-off-by: Jia Jia Reviewed-by: Peter Hilber Signed-off-by: Michael S. Tsirkin Message-ID: <20260507120801.3677552-1-physicalmtea@gmail.com> Signed-off-by: Sasha Levin --- drivers/virtio/virtio_rtc_driver.c | 28 ++++++++++++++++++++-------- 1 file changed, 20 insertions(+), 8 deletions(-) diff --git a/drivers/virtio/virtio_rtc_driver.c b/drivers/virtio/virtio_rtc_driver.c index a57d5e06e19d2d..4419735b0f0dcf 100644 --- a/drivers/virtio/virtio_rtc_driver.c +++ b/drivers/virtio/virtio_rtc_driver.c @@ -1257,6 +1257,15 @@ static int viortc_init_vqs(struct viortc_dev *viortc) return 0; } +static void __viortc_remove(struct viortc_dev *viortc) +{ + struct virtio_device *vdev = viortc->vdev; + + viortc_clocks_deinit(viortc); + virtio_reset_device(vdev); + vdev->config->del_vqs(vdev); +} + /** * viortc_probe() - probe a virtio_rtc virtio device * @vdev: virtio device @@ -1282,7 +1291,7 @@ static int viortc_probe(struct virtio_device *vdev) ret = viortc_init_vqs(viortc); if (ret) - return ret; + goto err_reset_vdev; virtio_device_ready(vdev); @@ -1329,10 +1338,7 @@ static void viortc_remove(struct virtio_device *vdev) { struct viortc_dev *viortc = vdev->priv; - viortc_clocks_deinit(viortc); - - virtio_reset_device(vdev); - vdev->config->del_vqs(vdev); + __viortc_remove(viortc); } static int viortc_freeze(struct virtio_device *dev) @@ -1353,9 +1359,11 @@ static int viortc_restore(struct virtio_device *dev) bool notify = false; int ret; + dev->config->del_vqs(dev); + ret = viortc_init_vqs(viortc); if (ret) - return ret; + goto err_remove; alarm_viortc_vq = &viortc->vqs[VIORTC_ALARMQ]; alarm_vq = alarm_viortc_vq->vq; @@ -1364,7 +1372,7 @@ static int viortc_restore(struct virtio_device *dev) ret = viortc_populate_vq(viortc, alarm_viortc_vq, VIORTC_ALARMQ_BUF_CAP, false); if (ret) - return ret; + goto err_remove; notify = virtqueue_kick_prepare(alarm_vq); } @@ -1372,8 +1380,12 @@ static int viortc_restore(struct virtio_device *dev) virtio_device_ready(dev); if (notify && !virtqueue_notify(alarm_vq)) - ret = -EIO; + return -EIO; + + return 0; +err_remove: + __viortc_remove(viortc); return ret; } -- 2.53.0