On 28/08/2026 at 18:19:05 +08, Xuanqiang Luo <[email protected]> wrote:
> From: Xuanqiang Luo <[email protected]> > > ieee802154_unregister_hw() unregisters the wpan netdevs before > destroying mac_wq. The RX path stores the receiving sub-interface > (sdata) in the queued MAC command descriptor without taking a > reference to the netdev. > > If mac802154_rx_mac_cmd_worker() runs after the netdev has been freed, > it dereferences the stale pointer and triggers a KASAN > slab-use-after-free: > > BUG: KASAN: slab-use-after-free in mac802154_rx_mac_cmd_worker+0xc0/0x498 > [mac802154] > Read of size 8 at addr ffff0000c6db0ba8 by task kworker/u16:3/61 > ... > Call trace: > show_stack+0x20/0x38 (C) > dump_stack_lvl+0x78/0x90 > print_address_description.constprop.0+0x88/0x398 > print_report+0xa8/0x278 > kasan_report+0xa8/0xf8 > __asan_load8+0x9c/0xc0 > mac802154_rx_mac_cmd_worker+0xc0/0x498 [mac802154] > process_one_work+0x334/0x8b8 > ... > Allocated by task 630: > kasan_save_stack+0x2c/0x58 > kasan_save_track+0x20/0x40 > kasan_save_alloc_info+0x40/0x58 > __kasan_kmalloc+0xa0/0xb8 > __kvmalloc_node_noprof+0x1e8/0x588 > alloc_netdev_mqs+0x74/0x7f0 > ieee802154_if_add+0xac/0x630 [mac802154] > ieee802154_register_hw+0x31c/0x3d0 [mac802154] > fakelb_add_one+0x250/0x318 [fakelb] > ... > Freed by task 652: > kasan_save_stack+0x2c/0x58 > kasan_save_track+0x20/0x40 > kasan_save_free_info+0x4c/0x78 > __kasan_slab_free+0x60/0x90 > kfree+0x194/0x478 > kvfree+0x44/0x60 > netdev_release+0x4c/0x68 > device_release+0xac/0x130 > kobject_cleanup+0x84/0x248 > kobject_put+0x98/0xf8 > netdev_run_todo+0x3a0/0x5e0 > rtnl_unlock+0x18/0x30 > ieee802154_unregister_hw+0x48/0x90 [mac802154] > fakelb_remove+0xe8/0x148 [fakelb] > > After killing local->tasklet, drain mac_wq before calling > ieee802154_remove_interfaces() so pending work completes before the > interfaces are unregistered. Do this without holding rtnl because scan > and beacon workers acquire it themselves. > > Fixes: d021d218f6d9 ("mac802154: Handle received BEACON_REQ") > Signed-off-by: Xuanqiang Luo <[email protected]> Missing Cc: stable. Reviewed-by: Miquel Raynal <[email protected]> Thanks, Miquèl
