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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 ffff88805f701c08 by task syz-executor/7563

CPU: 0 UID: 0 PID: 7563 Comm: syz-executor Not tainted 6.15.0-syzkaller-10769-g7d4e49a77d99 #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
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+0xcd/0x680 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+0xa03/0xc30 drivers/android/binderfs.c:210
 binderfs_fill_super+0x8d4/0x1360 drivers/android/binderfs.c:730
 vfs_get_super fs/super.c:1323 [inline]
 get_tree_nodev+0xda/0x190 fs/super.c:1342
 vfs_get_tree+0x8b/0x340 fs/super.c:1802
 do_new_mount fs/namespace.c:3856 [inline]
 path_mount+0x14d4/0x1f70 fs/namespace.c:4180
 do_mount fs/namespace.c:4193 [inline]
 __do_sys_mount fs/namespace.c:4404 [inline]
 __se_sys_mount fs/namespace.c:4381 [inline]
 __x64_sys_mount+0x28d/0x310 fs/namespace.c:4381
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xcd/0x490 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fb7cdf9010a
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:00007ffd2488f6a8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007fb7ce010e74 RCX: 00007fb7cdf9010a
RDX: 00007fb7ce0208cb RSI: 00007fb7ce010e74 RDI: 00007fb7ce0208cb
RBP: 00007fb7ce0110bd R08: 0000000000000000 R09: 00007fb7ce1b6738
R10: 0000000000000000 R11: 0000000000000246 R12: 00007fb7cdfec1a8
R13: 00007fb7cdfec180 R14: 0000000000000009 R15: 0000000000000000
 </TASK>

Allocated by task 5829:
 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+0x189/0xc30 drivers/android/binderfs.c:147
 binderfs_fill_super+0x8d4/0x1360 drivers/android/binderfs.c:730
 vfs_get_super fs/super.c:1323 [inline]
 get_tree_nodev+0xda/0x190 fs/super.c:1342
 vfs_get_tree+0x8b/0x340 fs/super.c:1802
 do_new_mount fs/namespace.c:3856 [inline]
 path_mount+0x14d4/0x1f70 fs/namespace.c:4180
 do_mount fs/namespace.c:4193 [inline]
 __do_sys_mount fs/namespace.c:4404 [inline]
 __se_sys_mount fs/namespace.c:4381 [inline]
 __x64_sys_mount+0x28d/0x310 fs/namespace.c:4381
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xcd/0x490 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Freed by task 5878:
 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
 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+0x9cf/0x1b70 kernel/workqueue.c:3238
 process_scheduled_works kernel/workqueue.c:3321 [inline]
 worker_thread+0x6c8/0xf10 kernel/workqueue.c:3402
 kthread+0x3c2/0x780 kernel/kthread.c:464
 ret_from_fork+0x5d4/0x6f0 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

The buggy address belongs to the object at ffff88805f701c00
 which belongs to the cache kmalloc-512 of size 512
The buggy address is located 8 bytes inside of
 freed 512-byte region [ffff88805f701c00, ffff88805f701e00)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x5f700
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 ffffea0000aa1000 dead000000000002
raw: 0000000000000000 0000000000100010 00000000f5000000 0000000000000000
head: 00fff00000000040 ffff88801b441c80 ffffea0000aa1000 dead000000000002
head: 0000000000000000 0000000000100010 00000000f5000000 0000000000000000
head: 00fff00000000002 ffffea00017dc001 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 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 12, tgid 12 (kworker/u8:0), ts 106783728195, free_ts 106781794456
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x1c0/0x230 mm/page_alloc.c:1704
 prep_new_page mm/page_alloc.c:1712 [inline]
 get_page_from_freelist+0x1321/0x3890 mm/page_alloc.c:3669
 __alloc_frozen_pages_noprof+0x261/0x23f0 mm/page_alloc.c:4959
 alloc_pages_mpol+0x1fb/0x550 mm/mempolicy.c:2419
 alloc_slab_page mm/slub.c:2450 [inline]
 allocate_slab mm/slub.c:2618 [inline]
 new_slab+0x23b/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_noprof+0xfb/0x3e0 mm/slub.c:4353
 kmalloc_noprof include/linux/slab.h:905 [inline]
 kzalloc_noprof include/linux/slab.h:1039 [inline]
 mca_alloc net/ipv6/mcast.c:884 [inline]
 __ipv6_dev_mc_inc+0x2b9/0xc10 net/ipv6/mcast.c:975
 addrconf_join_solict net/ipv6/addrconf.c:2242 [inline]
 addrconf_dad_begin net/ipv6/addrconf.c:4103 [inline]
 addrconf_dad_work+0x284/0x14e0 net/ipv6/addrconf.c:4231
 process_one_work+0x9cf/0x1b70 kernel/workqueue.c:3238
 process_scheduled_works kernel/workqueue.c:3321 [inline]
 worker_thread+0x6c8/0xf10 kernel/workqueue.c:3402
 kthread+0x3c2/0x780 kernel/kthread.c:464
 ret_from_fork+0x5d4/0x6f0 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
page last free pid 5829 tgid 5829 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1248 [inline]
 __free_frozen_pages+0x7fe/0x1180 mm/page_alloc.c:2706
 stack_depot_save_flags+0x354/0xa40 lib/stackdepot.c:678
 kasan_save_stack+0x42/0x60 mm/kasan/common.c:48
 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
 kasan_kmalloc include/linux/kasan.h:260 [inline]
 __do_kmalloc_node mm/slub.c:4327 [inline]
 __kmalloc_node_noprof+0x21e/0x500 mm/slub.c:4333
 kmalloc_array_node_noprof include/linux/slab.h:1020 [inline]
 alloc_slab_obj_exts+0x41/0xa0 mm/slub.c:1992
 account_slab mm/slub.c:2577 [inline]
 allocate_slab mm/slub.c:2637 [inline]
 new_slab+0x283/0x330 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]
 kmem_cache_alloc_lru_noprof+0xf4/0x3b0 mm/slub.c:4215
 proc_alloc_inode+0x25/0x200 fs/proc/inode.c:57
 alloc_inode+0x64/0x240 fs/inode.c:346
 new_inode+0x22/0x1c0 fs/inode.c:1145
 proc_get_inode+0x1d/0x780 fs/proc/inode.c:631
 proc_fill_super+0x41a/0x620 fs/proc/root.c:194

Memory state around the buggy address:
 ffff88805f701b00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff88805f701b80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff88805f701c00: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                      ^
 ffff88805f701c80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88805f701d00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
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