================================================================== BUG: KASAN: slab-use-after-free in __hlist_del include/linux/list.h:980 [inline] BUG: KASAN: slab-use-after-free in hlist_del_init include/linux/list.h:1008 [inline] BUG: KASAN: slab-use-after-free in batadv_forw_packet_steal+0x171/0x180 net/batman-adv/send.c:583 Write of size 8 at addr ffff888025db3800 by task kworker/u32:30/6858 CPU: 2 UID: 0 PID: 6858 Comm: kworker/u32:30 Not tainted 6.15.0-syzkaller-03478-gc89756bcf406 #0 PREEMPT(full) Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014 Workqueue: bat_events batadv_iv_send_outstanding_bat_ogm_packet Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:408 [inline] print_report+0xcd/0x680 mm/kasan/report.c:521 kasan_report+0xe0/0x110 mm/kasan/report.c:634 __hlist_del include/linux/list.h:980 [inline] hlist_del_init include/linux/list.h:1008 [inline] batadv_forw_packet_steal+0x171/0x180 net/batman-adv/send.c:583 batadv_iv_send_outstanding_bat_ogm_packet+0x23a/0x920 net/batman-adv/bat_iv_ogm.c:1724 process_one_work+0x9cc/0x1b70 kernel/workqueue.c:3238 process_scheduled_works kernel/workqueue.c:3319 [inline] worker_thread+0x6c8/0xf10 kernel/workqueue.c:3400 kthread+0x3c5/0x780 kernel/kthread.c:464 ret_from_fork+0x5d7/0x6f0 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Allocated by task 6861: kasan_save_stack+0x33/0x60 mm/kasan/common.c:47 kasan_save_track+0x14/0x30 mm/kasan/common.c:68 poison_kmalloc_redzone mm/kasan/common.c:377 [inline] __kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:394 kmalloc_noprof include/linux/slab.h:905 [inline] batadv_forw_packet_alloc+0x3ad/0x4e0 net/batman-adv/send.c:519 batadv_iv_ogm_aggregate_new+0x13c/0x4c0 net/batman-adv/bat_iv_ogm.c:571 batadv_iv_ogm_queue_add net/batman-adv/bat_iv_ogm.c:678 [inline] batadv_iv_ogm_schedule_buff+0xe77/0x14e0 net/batman-adv/bat_iv_ogm.c:857 batadv_iv_ogm_schedule net/batman-adv/bat_iv_ogm.c:876 [inline] batadv_iv_ogm_schedule net/batman-adv/bat_iv_ogm.c:869 [inline] batadv_iv_send_outstanding_bat_ogm_packet+0x329/0x920 net/batman-adv/bat_iv_ogm.c:1720 process_one_work+0x9cc/0x1b70 kernel/workqueue.c:3238 process_scheduled_works kernel/workqueue.c:3319 [inline] worker_thread+0x6c8/0xf10 kernel/workqueue.c:3400 kthread+0x3c5/0x780 kernel/kthread.c:464 ret_from_fork+0x5d7/0x6f0 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Freed by task 6858: kasan_save_stack+0x33/0x60 mm/kasan/common.c:47 kasan_save_track+0x14/0x30 mm/kasan/common.c:68 kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:576 poison_slab_object mm/kasan/common.c:247 [inline] __kasan_slab_free+0x51/0x70 mm/kasan/common.c:264 kasan_slab_free include/linux/kasan.h:233 [inline] slab_free_hook mm/slub.c:2380 [inline] slab_free mm/slub.c:4642 [inline] kfree+0x2b4/0x4d0 mm/slub.c:4841 batadv_iv_send_outstanding_bat_ogm_packet+0x26d/0x920 net/batman-adv/bat_iv_ogm.c:1726 process_one_work+0x9cc/0x1b70 kernel/workqueue.c:3238 process_scheduled_works kernel/workqueue.c:3319 [inline] worker_thread+0x6c8/0xf10 kernel/workqueue.c:3400 kthread+0x3c5/0x780 kernel/kthread.c:464 ret_from_fork+0x5d7/0x6f0 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Last potentially related work creation: kasan_save_stack+0x33/0x60 mm/kasan/common.c:47 kasan_record_aux_stack+0xa7/0xc0 mm/kasan/generic.c:548 insert_work+0x36/0x230 kernel/workqueue.c:2183 __queue_work+0x3f8/0x10f0 kernel/workqueue.c:2345 call_timer_fn+0x197/0x620 kernel/time/timer.c:1747 expire_timers kernel/time/timer.c:1793 [inline] __run_timers+0x569/0x960 kernel/time/timer.c:2372 __run_timer_base kernel/time/timer.c:2384 [inline] __run_timer_base kernel/time/timer.c:2376 [inline] run_timer_base+0x114/0x190 kernel/time/timer.c:2393 run_timer_softirq+0x1a/0x40 kernel/time/timer.c:2403 handle_softirqs+0x219/0x8e0 kernel/softirq.c:579 __do_softirq kernel/softirq.c:613 [inline] invoke_softirq kernel/softirq.c:453 [inline] __irq_exit_rcu+0x109/0x170 kernel/softirq.c:680 irq_exit_rcu+0x9/0x30 kernel/softirq.c:696 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1050 [inline] sysvec_apic_timer_interrupt+0xa4/0xc0 arch/x86/kernel/apic/apic.c:1050 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 The buggy address belongs to the object at ffff888025db3800 which belongs to the cache kmalloc-512 of size 512 The buggy address is located 0 bytes inside of freed 512-byte region [ffff888025db3800, ffff888025db3a00) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x25db0 head: order:2 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 00fff00000000040 ffff88801b442c80 ffffea0000484300 dead000000000002 raw: 0000000000000000 0000000000100010 00000000f5000000 0000000000000000 head: 00fff00000000040 ffff88801b442c80 ffffea0000484300 dead000000000002 head: 0000000000000000 0000000000100010 00000000f5000000 0000000000000000 head: 00fff00000000002 ffffea0000976c01 00000000ffffffff 00000000ffffffff head: ffffffffffffffff 0000000000000000 00000000ffffffff 0000000000000004 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 2, migratetype Unmovable, gfp_mask 0x252800(GFP_NOWAIT|__GFP_NORETRY|__GFP_COMP|__GFP_THISNODE), pid 5939, tgid 5939 (syz-executor), ts 51004338665, free_ts 50877259943 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x1c0/0x230 mm/page_alloc.c:1714 prep_new_page mm/page_alloc.c:1722 [inline] get_page_from_freelist+0x135c/0x3950 mm/page_alloc.c:3684 __alloc_pages_slowpath mm/page_alloc.c:4505 [inline] __alloc_frozen_pages_noprof+0x58b/0x23f0 mm/page_alloc.c:4987 alloc_slab_page mm/slub.c:2452 [inline] allocate_slab mm/slub.c:2618 [inline] new_slab+0x94/0x330 mm/slub.c:2672 ___slab_alloc+0xd9c/0x1940 mm/slub.c:3858 __slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3948 __slab_alloc_node mm/slub.c:4023 [inline] slab_alloc_node mm/slub.c:4184 [inline] __kmalloc_cache_node_noprof+0x100/0x420 mm/slub.c:4366 kmalloc_node_noprof include/linux/slab.h:928 [inline] alloc_fair_sched_group+0x20f/0x440 kernel/sched/fair.c:13382 sched_create_group+0x2d/0x80 kernel/sched/core.c:8977 cpu_cgroup_css_alloc kernel/sched/core.c:9123 [inline] cpu_cgroup_css_alloc+0x15/0x30 kernel/sched/core.c:9113 css_create kernel/cgroup/cgroup.c:5670 [inline] cgroup_apply_control_enable+0x4b7/0xc70 kernel/cgroup/cgroup.c:3282 cgroup_mkdir+0x39a/0x1160 kernel/cgroup/cgroup.c:5886 kernfs_iop_mkdir+0x108/0x190 fs/kernfs/dir.c:1266 vfs_mkdir+0x593/0x8c0 fs/namei.c:4366 do_mkdirat+0x304/0x3e0 fs/namei.c:4399 __do_sys_mkdirat fs/namei.c:4416 [inline] __se_sys_mkdirat fs/namei.c:4414 [inline] __ia32_sys_mkdirat+0x82/0xb0 fs/namei.c:4414 page last free pid 5951 tgid 5951 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1258 [inline] __free_frozen_pages+0x7f8/0x1180 mm/page_alloc.c:2721 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x4d/0x120 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x195/0x1e0 mm/kasan/quarantine.c:286 __kasan_slab_alloc+0x69/0x90 mm/kasan/common.c:329 kasan_slab_alloc include/linux/kasan.h:250 [inline] slab_post_alloc_hook mm/slub.c:4147 [inline] slab_alloc_node mm/slub.c:4196 [inline] kmem_cache_alloc_node_noprof+0x1d5/0x3b0 mm/slub.c:4248 __alloc_skb+0x2b2/0x380 net/core/skbuff.c:658 alloc_skb include/linux/skbuff.h:1340 [inline] netlink_alloc_large_skb+0x69/0x130 net/netlink/af_netlink.c:1187 netlink_sendmsg+0x6a1/0xdd0 net/netlink/af_netlink.c:1858 sock_sendmsg_nosec net/socket.c:712 [inline] __sock_sendmsg net/socket.c:727 [inline] __sys_sendto+0x4a0/0x520 net/socket.c:2180 __do_compat_sys_socketcall net/compat.c:475 [inline] __se_compat_sys_socketcall net/compat.c:423 [inline] __ia32_compat_sys_socketcall+0x625/0x770 net/compat.c:423 do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:83 [inline] __do_fast_syscall_32+0x7c/0x3a0 arch/x86/entry/syscall_32.c:306 do_fast_syscall_32+0x32/0x80 arch/x86/entry/syscall_32.c:331 entry_SYSENTER_compat_after_hwframe+0x84/0x8e Memory state around the buggy address: ffff888025db3700: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff888025db3780: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff888025db3800: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888025db3880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888025db3900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================