================================================================== BUG: KASAN: slab-use-after-free in taprio_dump_tc_entries net/sched/sch_taprio.c:2307 [inline] BUG: KASAN: slab-use-after-free in taprio_dump+0x857/0xd50 net/sched/sch_taprio.c:2420 Read of size 4 at addr ffff888051f4e4dc by task syz-executor.2/19412 CPU: 0 PID: 19412 Comm: syz-executor.2 Not tainted 6.8.0-rc7-syzkaller-00131-gb446631f355e #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/29/2024 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e7/0x2e0 lib/dump_stack.c:106 print_address_description mm/kasan/report.c:377 [inline] print_report+0x167/0x540 mm/kasan/report.c:488 kasan_report+0x142/0x180 mm/kasan/report.c:601 taprio_dump_tc_entries net/sched/sch_taprio.c:2307 [inline] taprio_dump+0x857/0xd50 net/sched/sch_taprio.c:2420 tc_fill_qdisc+0x6a9/0x1210 net/sched/sch_api.c:952 qdisc_notify+0x2ec/0x4b0 net/sched/sch_api.c:1053 tc_modify_qdisc+0x1c58/0x1e40 net/sched/sch_api.c:1748 rtnetlink_rcv_msg+0x885/0x1040 net/core/rtnetlink.c:6617 netlink_rcv_skb+0x1e3/0x430 net/netlink/af_netlink.c:2543 netlink_unicast_kernel net/netlink/af_netlink.c:1341 [inline] netlink_unicast+0x7ea/0x980 net/netlink/af_netlink.c:1367 netlink_sendmsg+0xa3b/0xd70 net/netlink/af_netlink.c:1908 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg+0x221/0x270 net/socket.c:745 ____sys_sendmsg+0x525/0x7d0 net/socket.c:2584 ___sys_sendmsg net/socket.c:2638 [inline] __sys_sendmsg+0x2b0/0x3a0 net/socket.c:2667 do_syscall_64+0xf9/0x240 entry_SYSCALL_64_after_hwframe+0x6f/0x77 RIP: 0033:0x7f66f0e7dda9 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f66f1b2b0c8 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007f66f0fabf80 RCX: 00007f66f0e7dda9 RDX: 0000000000000000 RSI: 00000000200007c0 RDI: 0000000000000004 RBP: 00007f66f0eca47a R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000000b R14: 00007f66f0fabf80 R15: 00007ffcea057cc8 Allocated by task 19401: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3f/0x80 mm/kasan/common.c:68 poison_kmalloc_redzone mm/kasan/common.c:370 [inline] __kasan_kmalloc+0x98/0xb0 mm/kasan/common.c:387 kasan_kmalloc include/linux/kasan.h:211 [inline] kmalloc_trace+0x1d6/0x360 mm/slub.c:4012 kmalloc include/linux/slab.h:590 [inline] kzalloc include/linux/slab.h:711 [inline] taprio_change+0x109b/0x57d0 net/sched/sch_taprio.c:1881 qdisc_change net/sched/sch_api.c:1416 [inline] tc_modify_qdisc+0x190d/0x1e40 net/sched/sch_api.c:1746 rtnetlink_rcv_msg+0x885/0x1040 net/core/rtnetlink.c:6617 netlink_rcv_skb+0x1e3/0x430 net/netlink/af_netlink.c:2543 netlink_unicast_kernel net/netlink/af_netlink.c:1341 [inline] netlink_unicast+0x7ea/0x980 net/netlink/af_netlink.c:1367 netlink_sendmsg+0xa3b/0xd70 net/netlink/af_netlink.c:1908 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg+0x221/0x270 net/socket.c:745 ____sys_sendmsg+0x525/0x7d0 net/socket.c:2584 ___sys_sendmsg net/socket.c:2638 [inline] __sys_sendmsg+0x2b0/0x3a0 net/socket.c:2667 do_syscall_64+0xf9/0x240 entry_SYSCALL_64_after_hwframe+0x6f/0x77 Freed by task 19409: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3f/0x80 mm/kasan/common.c:68 kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:589 poison_slab_object+0xa6/0xe0 mm/kasan/common.c:240 __kasan_slab_free+0x37/0x60 mm/kasan/common.c:256 kasan_slab_free include/linux/kasan.h:184 [inline] slab_free_hook mm/slub.c:2121 [inline] slab_free mm/slub.c:4299 [inline] kfree+0x14a/0x380 mm/slub.c:4409 rcu_do_batch kernel/rcu/tree.c:2190 [inline] rcu_core+0xd76/0x1810 kernel/rcu/tree.c:2465 __do_softirq+0x2bb/0x942 kernel/softirq.c:553 Last potentially related work creation: kasan_save_stack+0x3f/0x60 mm/kasan/common.c:47 __kasan_record_aux_stack+0xac/0xc0 mm/kasan/generic.c:551 __call_rcu_common kernel/rcu/tree.c:2715 [inline] call_rcu+0x167/0xa80 kernel/rcu/tree.c:2829 switch_schedules net/sched/sch_taprio.c:210 [inline] advance_sched+0x940/0xca0 net/sched/sch_taprio.c:984 __run_hrtimer kernel/time/hrtimer.c:1689 [inline] __hrtimer_run_queues+0x594/0xd00 kernel/time/hrtimer.c:1753 hrtimer_interrupt+0x396/0x990 kernel/time/hrtimer.c:1815 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1065 [inline] __sysvec_apic_timer_interrupt+0x107/0x3a0 arch/x86/kernel/apic/apic.c:1082 sysvec_apic_timer_interrupt+0x92/0xb0 arch/x86/kernel/apic/apic.c:1076 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:649 The buggy address belongs to the object at ffff888051f4e400 which belongs to the cache kmalloc-512 of size 512 The buggy address is located 220 bytes inside of freed 512-byte region [ffff888051f4e400, ffff888051f4e600) The buggy address belongs to the physical page: page:ffffea000147d300 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x51f4c head:ffffea000147d300 order:2 entire_mapcount:0 nr_pages_mapped:0 pincount:0 flags: 0xfff00000000840(slab|head|node=0|zone=1|lastcpupid=0x7ff) page_type: 0xffffffff() raw: 00fff00000000840 ffff888014c41c80 dead000000000100 dead000000000122 raw: 0000000000000000 0000000080100010 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 2, migratetype Unmovable, gfp_mask 0x152820(GFP_ATOMIC|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_HARDWALL), pid 19341, tgid 19341 (kworker/u4:25), ts 2748518364331, free_ts 2733980539547 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x1ea/0x210 mm/page_alloc.c:1533 prep_new_page mm/page_alloc.c:1540 [inline] get_page_from_freelist+0x33ea/0x3580 mm/page_alloc.c:3311 __alloc_pages+0x255/0x680 mm/page_alloc.c:4567 __alloc_pages_node include/linux/gfp.h:238 [inline] alloc_pages_node include/linux/gfp.h:261 [inline] alloc_slab_page+0x5f/0x160 mm/slub.c:2190 allocate_slab mm/slub.c:2354 [inline] new_slab+0x84/0x2f0 mm/slub.c:2407 ___slab_alloc+0xd17/0x13e0 mm/slub.c:3540 __slab_alloc mm/slub.c:3625 [inline] __slab_alloc_node mm/slub.c:3678 [inline] slab_alloc_node mm/slub.c:3850 [inline] kmalloc_trace+0x264/0x360 mm/slub.c:4007 kmalloc include/linux/slab.h:590 [inline] batadv_forw_packet_alloc+0x19c/0x3b0 net/batman-adv/send.c:519 batadv_iv_ogm_aggregate_new net/batman-adv/bat_iv_ogm.c:562 [inline] batadv_iv_ogm_queue_add+0x6da/0xbf0 net/batman-adv/bat_iv_ogm.c:670 batadv_iv_ogm_schedule_buff net/batman-adv/bat_iv_ogm.c:849 [inline] batadv_iv_ogm_schedule+0xc4d/0x1090 net/batman-adv/bat_iv_ogm.c:868 batadv_iv_send_outstanding_bat_ogm_packet+0x6fe/0x810 net/batman-adv/bat_iv_ogm.c:1712 process_one_work kernel/workqueue.c:2633 [inline] process_scheduled_works+0x913/0x1420 kernel/workqueue.c:2706 worker_thread+0xa5f/0x1000 kernel/workqueue.c:2787 kthread+0x2ef/0x390 kernel/kthread.c:388 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1b/0x30 arch/x86/entry/entry_64.S:243 page last free pid 12457 tgid 12453 stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1140 [inline] free_unref_page_prepare+0x968/0xa90 mm/page_alloc.c:2346 free_unref_page+0x37/0x3f0 mm/page_alloc.c:2486 mm_free_pgd kernel/fork.c:801 [inline] __mmdrop+0xb8/0x3d0 kernel/fork.c:917 exit_mm+0x21f/0x310 kernel/exit.c:569 do_exit+0x9af/0x2740 kernel/exit.c:858 do_group_exit+0x206/0x2c0 kernel/exit.c:1020 get_signal+0x176d/0x1850 kernel/signal.c:2893 arch_do_signal_or_restart+0x96/0x860 arch/x86/kernel/signal.c:310 exit_to_user_mode_loop kernel/entry/common.c:105 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:201 [inline] syscall_exit_to_user_mode+0xc8/0x360 kernel/entry/common.c:212 do_syscall_64+0x108/0x240 arch/x86/entry/common.c:89 entry_SYSCALL_64_after_hwframe+0x6f/0x77 Memory state around the buggy address: ffff888051f4e380: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff888051f4e400: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff888051f4e480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888051f4e500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888051f4e580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================