7.3-stable review patch. If anyone has any objections, please let me know. ------------------ From: Weiming Shi commit 1234707482053f1d1ac7c5756207d2c29057974c upstream. virtio-net uses a boolean to gate rx_mode_work during device teardown. The flag is changed under RTNL, but ndo_set_rx_mode checks it under the address-list lock. A callback can therefore pass the check and enqueue work after teardown has flushed it. The work is also enabled before late probe operations that can fail, allowing probe unwind to free the netdev with work still queued. KASAN reports the worker using a virtqueue that probe unwind already freed: BUG: KASAN: slab-use-after-free in virtqueue_add_split Workqueue: events virtnet_rx_mode_work Call Trace: virtqueue_add_split (drivers/virtio/virtio_ring.c:706) virtqueue_add_sgs (drivers/virtio/virtio_ring.c:2839) virtnet_send_command_reply (drivers/net/virtio_net.c:3565) virtnet_rx_mode_work (drivers/net/virtio_net.c:3833) process_one_work (kernel/workqueue.c:3322) worker_thread (kernel/workqueue.c:3405) Freed by task 119: kfree (mm/slub.c:6625) vp_del_vq.isra.0 (drivers/virtio/virtio_pci_common.c:259) vp_del_vqs (drivers/virtio/virtio_pci_common.c:285) virtnet_probe (drivers/net/virtio_net.c:7129) Use the workqueue disable mechanism to atomically reject new queue attempts and drain running work. Keep work disabled until probe succeeds or restore has reattached the netdev, then enable it and replay receive-mode state for a running interface. Disable it before resource teardown in freeze and remove. Fixes: b9f7425239a0 ("virtio-net: convert rx mode setting to use workqueue") Cc: stable@vger.kernel.org Reported-by: Assisted-by: LLM Signed-off-by: Weiming Shi Link: https://patch.msgid.link/20261017114237.2786302-2-bestswngs@gmail.com Signed-off-by: Paolo Abeni Signed-off-by: Greg Kroah-Hartman --- drivers/net/virtio_net.c | 26 +++++++++----------------- 1 file changed, 9 insertions(+), 17 deletions(-) --- a/drivers/net/virtio_net.c +++ b/drivers/net/virtio_net.c @@ -441,9 +441,6 @@ struct virtnet_info { /* Work struct for setting rx mode */ struct work_struct rx_mode_work; - /* OK to queue work setting RX mode? */ - bool rx_mode_work_enabled; - /* Does the affinity hint is set for virtqueues? */ bool affinity_hint_set; @@ -710,16 +707,13 @@ static void virtnet_rq_free_buf(struct v static void enable_rx_mode_work(struct virtnet_info *vi) { - rtnl_lock(); - vi->rx_mode_work_enabled = true; - rtnl_unlock(); + if (enable_work(&vi->rx_mode_work) && netif_running(vi->dev)) + schedule_work(&vi->rx_mode_work); } static void disable_rx_mode_work(struct virtnet_info *vi) { - rtnl_lock(); - vi->rx_mode_work_enabled = false; - rtnl_unlock(); + disable_work_sync(&vi->rx_mode_work); } static void virtqueue_napi_schedule(struct napi_struct *napi, @@ -3925,8 +3919,7 @@ static void virtnet_set_rx_mode(struct n { struct virtnet_info *vi = netdev_priv(dev); - if (vi->rx_mode_work_enabled) - schedule_work(&vi->rx_mode_work); + schedule_work(&vi->rx_mode_work); } static int virtnet_vlan_rx_add_vid(struct net_device *dev, @@ -5742,7 +5735,6 @@ static void virtnet_freeze_down(struct v /* Make sure no work handler is accessing the device */ flush_work(&vi->config_work); disable_rx_mode_work(vi); - flush_work(&vi->rx_mode_work); if (netif_running(vi->dev)) { rtnl_lock(); @@ -5772,8 +5764,6 @@ static int virtnet_restore_up(struct vir virtio_device_ready(vdev); - enable_rx_mode_work(vi); - if (netif_running(vi->dev)) { rtnl_lock(); err = virtnet_open(vi->dev); @@ -5785,6 +5775,8 @@ static int virtnet_restore_up(struct vir netif_tx_lock_bh(vi->dev); netif_device_attach(vi->dev); netif_tx_unlock_bh(vi->dev); + + enable_rx_mode_work(vi); return 0; err_destroy_pools: @@ -6880,6 +6872,7 @@ static int virtnet_probe(struct virtio_d INIT_WORK(&vi->config_work, virtnet_config_changed_work); INIT_WORK(&vi->rx_mode_work, virtnet_rx_mode_work); + disable_work(&vi->rx_mode_work); if (virtio_has_feature(vdev, VIRTIO_NET_F_MRG_RXBUF)) { vi->mergeable_rx_bufs = true; @@ -7038,8 +7031,6 @@ static int virtnet_probe(struct virtio_d if (vi->has_rss || vi->has_rss_hash_report) virtnet_init_default_rss(vi); - enable_rx_mode_work(vi); - for (i = 0; i < ARRAY_SIZE(guest_offloads); i++) { unsigned int fbit; @@ -7143,6 +7134,8 @@ static int virtnet_probe(struct virtio_d goto free_unregister_netdev; } + enable_rx_mode_work(vi); + pr_debug("virtnet: registered device %s with %d RX and TX vq's\n", dev->name, max_queue_pairs); @@ -7195,7 +7188,6 @@ static void virtnet_remove(struct virtio /* Make sure no work handler is accessing the device. */ flush_work(&vi->config_work); disable_rx_mode_work(vi); - flush_work(&vi->rx_mode_work); virtnet_free_irq_moder(vi);