4.14-stable review patch. If anyone has any objections, please let me know.
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From: Stefan Wahren wahrenst@gmx.net
[ Upstream commit f4e6064c97c050bd9904925ff7d53d0c9954fc7b ]
The qca_spi driver stop and restart the SPI kernel thread (via ndo_stop & ndo_open) in case of TX ring changes. This is a big issue because it allows userspace to prevent restart of the SPI kernel thread (via signals). A subsequent change of TX ring wrongly assume a valid spi_thread pointer which result in a crash.
So prevent this by stopping the network traffic handling and temporary park the SPI thread.
Fixes: 291ab06ecf67 ("net: qualcomm: new Ethernet over SPI driver for QCA7000") Signed-off-by: Stefan Wahren wahrenst@gmx.net Link: https://lore.kernel.org/r/20231206141222.52029-2-wahrenst@gmx.net Signed-off-by: Jakub Kicinski kuba@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/net/ethernet/qualcomm/qca_debug.c | 9 ++++----- drivers/net/ethernet/qualcomm/qca_spi.c | 12 ++++++++++++ 2 files changed, 16 insertions(+), 5 deletions(-)
diff --git a/drivers/net/ethernet/qualcomm/qca_debug.c b/drivers/net/ethernet/qualcomm/qca_debug.c index 92b6be9c44296..858c39cdae08a 100644 --- a/drivers/net/ethernet/qualcomm/qca_debug.c +++ b/drivers/net/ethernet/qualcomm/qca_debug.c @@ -275,7 +275,6 @@ qcaspi_get_ringparam(struct net_device *dev, struct ethtool_ringparam *ring) static int qcaspi_set_ringparam(struct net_device *dev, struct ethtool_ringparam *ring) { - const struct net_device_ops *ops = dev->netdev_ops; struct qcaspi *qca = netdev_priv(dev);
if ((ring->rx_pending) || @@ -283,14 +282,14 @@ qcaspi_set_ringparam(struct net_device *dev, struct ethtool_ringparam *ring) (ring->rx_jumbo_pending)) return -EINVAL;
- if (netif_running(dev)) - ops->ndo_stop(dev); + if (qca->spi_thread) + kthread_park(qca->spi_thread);
qca->txr.count = max_t(u32, ring->tx_pending, TX_RING_MIN_LEN); qca->txr.count = min_t(u16, qca->txr.count, TX_RING_MAX_LEN);
- if (netif_running(dev)) - ops->ndo_open(dev); + if (qca->spi_thread) + kthread_unpark(qca->spi_thread);
return 0; } diff --git a/drivers/net/ethernet/qualcomm/qca_spi.c b/drivers/net/ethernet/qualcomm/qca_spi.c index 0c454eeb3bd8e..4142554dc29e3 100644 --- a/drivers/net/ethernet/qualcomm/qca_spi.c +++ b/drivers/net/ethernet/qualcomm/qca_spi.c @@ -552,6 +552,18 @@ qcaspi_spi_thread(void *data) netdev_info(qca->net_dev, "SPI thread created\n"); while (!kthread_should_stop()) { set_current_state(TASK_INTERRUPTIBLE); + if (kthread_should_park()) { + netif_tx_disable(qca->net_dev); + netif_carrier_off(qca->net_dev); + qcaspi_flush_tx_ring(qca); + kthread_parkme(); + if (qca->sync == QCASPI_SYNC_READY) { + netif_carrier_on(qca->net_dev); + netif_wake_queue(qca->net_dev); + } + continue; + } + if ((qca->intr_req == qca->intr_svc) && !qca->txr.skb[qca->txr.head]) schedule();