================================================================== BUG: KASAN: use-after-free in __tcp_hdrlen include/linux/tcp.h:31 [inline] BUG: KASAN: use-after-free in qdisc_pkt_len_segs_init+0x7f7/0xa30 net/core/dev.c:4142 Read of size 2 at addr ffff8881767dddb4 by task kworker/u8:0/12 CPU: 0 UID: 0 PID: 12 Comm: kworker/u8:0 Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026 Workqueue: events_unbound macvlan_process_broadcast Call Trace: dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120 print_address_description+0x55/0x1e0 mm/kasan/report.c:378 print_report+0x58/0x70 mm/kasan/report.c:482 kasan_report+0x117/0x150 mm/kasan/report.c:595 __tcp_hdrlen include/linux/tcp.h:31 [inline] qdisc_pkt_len_segs_init+0x7f7/0xa30 net/core/dev.c:4142 __dev_queue_xmit+0x27f/0x37f0 net/core/dev.c:4784 dev_queue_xmit include/linux/netdevice.h:3436 [inline] br_dev_queue_push_xmit+0x370/0x4b0 net/bridge/br_forward.c:53 NF_HOOK+0x360/0x3f0 include/linux/netfilter.h:318 br_forward_finish+0xd3/0x130 net/bridge/br_forward.c:66 NF_HOOK+0x360/0x3f0 include/linux/netfilter.h:318 __br_forward+0x397/0x540 net/bridge/br_forward.c:115 deliver_clone net/bridge/br_forward.c:131 [inline] maybe_deliver net/bridge/br_forward.c:191 [inline] br_flood+0x3e6/0x8d0 net/bridge/br_forward.c:245 br_handle_frame_finish+0x1175/0x1990 net/bridge/br_input.c:229 nf_hook_bridge_pre net/bridge/br_input.c:313 [inline] br_handle_frame+0x81b/0x1510 net/bridge/br_input.c:442 __netif_receive_skb_core+0x989/0x30b0 net/core/dev.c:6093 __netif_receive_skb_one_core net/core/dev.c:6204 [inline] __netif_receive_skb net/core/dev.c:6319 [inline] process_backlog+0x706/0x1860 net/core/dev.c:6670 __napi_poll+0xaa/0x330 net/core/dev.c:7729 napi_poll net/core/dev.c:7792 [inline] net_rx_action+0x61d/0xf50 net/core/dev.c:7949 handle_softirqs+0x225/0x840 kernel/softirq.c:622 do_softirq+0x76/0xd0 kernel/softirq.c:523 __local_bh_enable_ip+0xf8/0x130 kernel/softirq.c:450 local_bh_enable include/linux/bottom_half.h:33 [inline] netif_rx+0x83/0x90 net/core/dev.c:5779 macvlan_broadcast+0x375/0x630 drivers/net/macvlan.c:292 macvlan_multicast_rx drivers/net/macvlan.c:-1 [inline] macvlan_process_broadcast+0x437/0x660 drivers/net/macvlan.c:344 process_one_work kernel/workqueue.c:3322 [inline] process_scheduled_works+0xa8e/0x14e0 kernel/workqueue.c:3405 worker_thread+0xa47/0xfb0 kernel/workqueue.c:3486 kthread+0x388/0x470 kernel/kthread.c:436 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x1767dd flags: 0x57ff00000000000(node=1|zone=2|lastcpupid=0x7ff) raw: 057ff00000000000 ffffea0005d9f748 ffffea0005d9f748 0000000000000000 raw: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner info is not present (never set?) Memory state around the buggy address: ffff8881767ddc80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffff8881767ddd00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff >ffff8881767ddd80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ^ ffff8881767dde00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffff8881767dde80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ==================================================================