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BUG: KASAN: slab-use-after-free in hlist_add_head include/linux/list.h:1026 [inline]
BUG: KASAN: slab-use-after-free in binder_add_device+0xa4/0xb0 drivers/android/binder.c:6932
Write of size 8 at addr ffff88807dc0b808 by task syz-executor/9696

CPU: 0 UID: 0 PID: 9696 Comm: syz-executor Not tainted 6.15.0-rc4-syzkaller-00052-g4f79eaa2ceac #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/19/2025
Call Trace:
 <TASK>
 __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+0xc3/0x670 mm/kasan/report.c:521
 kasan_report+0xe0/0x110 mm/kasan/report.c:634
 hlist_add_head include/linux/list.h:1026 [inline]
 binder_add_device+0xa4/0xb0 drivers/android/binder.c:6932
 binderfs_binder_device_create.isra.0+0x95f/0xb70 drivers/android/binderfs.c:210
 binderfs_fill_super+0x8d4/0x1360 drivers/android/binderfs.c:730
 vfs_get_super fs/super.c:1280 [inline]
 get_tree_nodev+0xda/0x190 fs/super.c:1299
 vfs_get_tree+0x8b/0x340 fs/super.c:1759
 do_new_mount fs/namespace.c:3884 [inline]
 path_mount+0x14d4/0x1f20 fs/namespace.c:4211
 do_mount fs/namespace.c:4224 [inline]
 __do_sys_mount fs/namespace.c:4435 [inline]
 __se_sys_mount fs/namespace.c:4412 [inline]
 __x64_sys_mount+0x28d/0x310 fs/namespace.c:4412
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xcd/0x260 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f717739010a
Code: d8 64 89 02 48 c7 c0 ff ff ff ff eb a6 e8 de 1a 00 00 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 49 89 ca b8 a5 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffee97a05a8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007f7177410e74 RCX: 00007f717739010a
RDX: 00007f71774208cb RSI: 00007f7177410e74 RDI: 00007f71774208cb
RBP: 00007f71774110bd R08: 0000000000000000 R09: 00007f71775b6738
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f71773ec1a8
R13: 00007f71773ec180 R14: 0000000000000009 R15: 0000000000000000
 </TASK>

Allocated by task 9608:
 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]
 kzalloc_noprof include/linux/slab.h:1039 [inline]
 binderfs_binder_device_create.isra.0+0x17a/0xb70 drivers/android/binderfs.c:147
 binderfs_fill_super+0x8d4/0x1360 drivers/android/binderfs.c:730
 vfs_get_super fs/super.c:1280 [inline]
 get_tree_nodev+0xda/0x190 fs/super.c:1299
 vfs_get_tree+0x8b/0x340 fs/super.c:1759
 do_new_mount fs/namespace.c:3884 [inline]
 path_mount+0x14d4/0x1f20 fs/namespace.c:4211
 do_mount fs/namespace.c:4224 [inline]
 __do_sys_mount fs/namespace.c:4435 [inline]
 __se_sys_mount fs/namespace.c:4412 [inline]
 __x64_sys_mount+0x28d/0x310 fs/namespace.c:4412
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xcd/0x260 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Freed by task 24:
 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:2398 [inline]
 slab_free mm/slub.c:4656 [inline]
 kfree+0x2b6/0x4d0 mm/slub.c:4855
 binder_free_proc drivers/android/binder.c:5248 [inline]
 binder_proc_dec_tmpref drivers/android/binder.c:1565 [inline]
 binder_proc_dec_tmpref+0x4c3/0x590 drivers/android/binder.c:1558
 binder_deferred_release drivers/android/binder.c:6292 [inline]
 binder_deferred_func+0xe87/0x12c0 drivers/android/binder.c:6319
 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+0x3c2/0x780 kernel/kthread.c:464
 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:153
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

The buggy address belongs to the object at ffff88807dc0b800
 which belongs to the cache kmalloc-512 of size 512
The buggy address is located 8 bytes inside of
 freed 512-byte region [ffff88807dc0b800, ffff88807dc0ba00)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x7dc08
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 ffff88801b441c80 dead000000000100 dead000000000122
raw: 0000000000000000 0000000000100010 00000000f5000000 0000000000000000
head: 00fff00000000040 ffff88801b441c80 dead000000000100 dead000000000122
head: 0000000000000000 0000000000100010 00000000f5000000 0000000000000000
head: 00fff00000000002 ffffea0001f70201 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 0x52820(GFP_ATOMIC|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP), pid 5806, tgid 5806 (syz-executor), ts 60637461120, free_ts 60527820689
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x181/0x1b0 mm/page_alloc.c:1718
 prep_new_page mm/page_alloc.c:1726 [inline]
 get_page_from_freelist+0x135c/0x3920 mm/page_alloc.c:3688
 __alloc_frozen_pages_noprof+0x263/0x23a0 mm/page_alloc.c:4970
 alloc_pages_mpol+0x1fb/0x550 mm/mempolicy.c:2301
 alloc_slab_page mm/slub.c:2468 [inline]
 allocate_slab mm/slub.c:2632 [inline]
 new_slab+0x244/0x340 mm/slub.c:2686
 ___slab_alloc+0xd9c/0x1940 mm/slub.c:3872
 __slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3962
 __slab_alloc_node mm/slub.c:4037 [inline]
 slab_alloc_node mm/slub.c:4198 [inline]
 __do_kmalloc_node mm/slub.c:4340 [inline]
 __kmalloc_noprof+0x2f2/0x510 mm/slub.c:4353
 kmalloc_noprof include/linux/slab.h:909 [inline]
 kzalloc_noprof include/linux/slab.h:1039 [inline]
 fib6_info_alloc+0x40/0x160 net/ipv6/ip6_fib.c:155
 ip6_route_info_create+0x33f/0x18e0 net/ipv6/route.c:3802
 addrconf_f6i_alloc+0x391/0x670 net/ipv6/route.c:4631
 fixup_permanent_addr net/ipv6/addrconf.c:3584 [inline]
 addrconf_permanent_addr net/ipv6/addrconf.c:3623 [inline]
 addrconf_notify+0x10a1/0x19e0 net/ipv6/addrconf.c:3695
 notifier_call_chain+0xb9/0x410 kernel/notifier.c:85
 call_netdevice_notifiers_info+0xbe/0x140 net/core/dev.c:2176
 call_netdevice_notifiers_extack net/core/dev.c:2214 [inline]
 call_netdevice_notifiers net/core/dev.c:2228 [inline]
 __dev_notify_flags+0x12c/0x2e0 net/core/dev.c:9405
 netif_change_flags+0x108/0x160 net/core/dev.c:9434
page last free pid 971 tgid 971 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1262 [inline]
 __free_frozen_pages+0x69d/0xff0 mm/page_alloc.c:2725
 qlink_free mm/kasan/quarantine.c:163 [inline]
 qlist_free_all+0x4e/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:4161 [inline]
 slab_alloc_node mm/slub.c:4210 [inline]
 __kmalloc_cache_noprof+0x1f1/0x3e0 mm/slub.c:4367
 kmalloc_noprof include/linux/slab.h:905 [inline]
 kzalloc_noprof include/linux/slab.h:1039 [inline]
 nsim_fib6_rt_create drivers/net/netdevsim/fib.c:547 [inline]
 nsim_fib6_rt_insert drivers/net/netdevsim/fib.c:752 [inline]
 nsim_fib6_event drivers/net/netdevsim/fib.c:856 [inline]
 nsim_fib_event drivers/net/netdevsim/fib.c:889 [inline]
 nsim_fib_event_work+0x17f5/0x2e80 drivers/net/netdevsim/fib.c:1493
 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+0x3c2/0x780 kernel/kthread.c:464
 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:153
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

Memory state around the buggy address:
 ffff88807dc0b700: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff88807dc0b780: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff88807dc0b800: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                      ^
 ffff88807dc0b880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88807dc0b900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
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