syzbot

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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+0x5f/0xa0 drivers/android/binder.c:6932
Write of size 8 at addr ffff888031a12408 by task syz-executor301/5823

CPU: 1 UID: 0 PID: 5823 Comm: syz-executor301 Not tainted 6.15.0-rc5-syzkaller-00022-g01f95500a162 #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/29/2025
Call Trace:
 <TASK>
 dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
 print_address_description mm/kasan/report.c:408 [inline]
 print_report+0xb4/0x290 mm/kasan/report.c:521
 kasan_report+0x118/0x150 mm/kasan/report.c:634
 hlist_add_head include/linux/list.h:1026 [inline]
 binder_add_device+0x5f/0xa0 drivers/android/binder.c:6932
 binderfs_binder_device_create+0x8b7/0xaf0 drivers/android/binderfs.c:210
 binderfs_fill_super+0xa0e/0xe90 drivers/android/binderfs.c:730
 vfs_get_super fs/super.c:1280 [inline]
 get_tree_nodev+0xbb/0x150 fs/super.c:1299
 vfs_get_tree+0x92/0x2b0 fs/super.c:1759
 do_new_mount+0x24a/0xa40 fs/namespace.c:3884
 do_mount fs/namespace.c:4224 [inline]
 __do_sys_mount fs/namespace.c:4435 [inline]
 __se_sys_mount+0x317/0x410 fs/namespace.c:4412
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xf6/0x210 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fee80b7e68a
Code: d8 64 89 02 48 c7 c0 ff ff ff ff eb a6 e8 6e 07 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 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffc2210f728 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007fee80bbf038 RCX: 00007fee80b7e68a
RDX: 00007fee80bbf1c8 RSI: 00007fee80bbf038 RDI: 00007fee80bbf1c8
RBP: 00007fee80bbf198 R08: 0000000000000000 R09: 0000000000000140
R10: 0000000000000000 R11: 0000000000000246 R12: 00007fee80bc4c9c
R13: 00007fee80bbf100 R14: 0000000000000001 R15: 0000000000000001
 </TASK>

Allocated by task 5821:
 kasan_save_stack mm/kasan/common.c:47 [inline]
 kasan_save_track+0x3e/0x80 mm/kasan/common.c:68
 poison_kmalloc_redzone mm/kasan/common.c:377 [inline]
 __kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:394
 kasan_kmalloc include/linux/kasan.h:260 [inline]
 __kmalloc_cache_noprof+0x230/0x3d0 mm/slub.c:4358
 kmalloc_noprof include/linux/slab.h:905 [inline]
 kzalloc_noprof include/linux/slab.h:1039 [inline]
 binderfs_binder_device_create+0x17f/0xaf0 drivers/android/binderfs.c:147
 binderfs_fill_super+0xa0e/0xe90 drivers/android/binderfs.c:730
 vfs_get_super fs/super.c:1280 [inline]
 get_tree_nodev+0xbb/0x150 fs/super.c:1299
 vfs_get_tree+0x92/0x2b0 fs/super.c:1759
 do_new_mount+0x24a/0xa40 fs/namespace.c:3884
 do_mount fs/namespace.c:4224 [inline]
 __do_sys_mount fs/namespace.c:4435 [inline]
 __se_sys_mount+0x317/0x410 fs/namespace.c:4412
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xf6/0x210 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Freed by task 5829:
 kasan_save_stack mm/kasan/common.c:47 [inline]
 kasan_save_track+0x3e/0x80 mm/kasan/common.c:68
 kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:576
 poison_slab_object mm/kasan/common.c:247 [inline]
 __kasan_slab_free+0x62/0x70 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+0x193/0x440 mm/slub.c:4841
 binder_free_proc drivers/android/binder.c:5248 [inline]
 binder_proc_dec_tmpref+0x228/0x4f0 drivers/android/binder.c:1565
 binder_deferred_release drivers/android/binder.c:6292 [inline]
 binder_deferred_func+0x13a5/0x1520 drivers/android/binder.c:6319
 process_one_work kernel/workqueue.c:3238 [inline]
 process_scheduled_works+0xade/0x17a0 kernel/workqueue.c:3319
 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3400
 kthread+0x711/0x8a0 kernel/kthread.c:464
 ret_from_fork+0x4e/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 ffff888031a12400
 which belongs to the cache kmalloc-512 of size 512
The buggy address is located 8 bytes inside of
 freed 512-byte region [ffff888031a12400, ffff888031a12600)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x31a10
head: order:2 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
anon flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000040 ffff88801a041c80 0000000000000000 dead000000000001
raw: 0000000000000000 0000000000100010 00000000f5000000 0000000000000000
head: 00fff00000000040 ffff88801a041c80 0000000000000000 dead000000000001
head: 0000000000000000 0000000000100010 00000000f5000000 0000000000000000
head: 00fff00000000002 ffffea0000c68401 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 1, tgid 1 (swapper/0), ts 24974876976, free_ts 0
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x1d8/0x230 mm/page_alloc.c:1718
 prep_new_page mm/page_alloc.c:1726 [inline]
 get_page_from_freelist+0x21ce/0x22b0 mm/page_alloc.c:3688
 __alloc_frozen_pages_noprof+0x181/0x370 mm/page_alloc.c:4970
 alloc_pages_mpol+0x232/0x4a0 mm/mempolicy.c:2301
 alloc_slab_page mm/slub.c:2450 [inline]
 allocate_slab+0x8a/0x3b0 mm/slub.c:2618
 new_slab mm/slub.c:2672 [inline]
 ___slab_alloc+0xbfc/0x1480 mm/slub.c:3858
 __slab_alloc mm/slub.c:3948 [inline]
 __slab_alloc_node mm/slub.c:4023 [inline]
 slab_alloc_node mm/slub.c:4184 [inline]
 __do_kmalloc_node mm/slub.c:4326 [inline]
 __kmalloc_node_track_caller_noprof+0x2f8/0x4e0 mm/slub.c:4346
 __do_krealloc mm/slub.c:4904 [inline]
 krealloc_noprof+0x122/0x330 mm/slub.c:4957
 add_sysfs_param+0xc9/0xa20 kernel/params.c:654
 kernel_add_sysfs_param+0xb4/0x130 kernel/params.c:811
 param_sysfs_builtin+0x1de/0x290 kernel/params.c:850
 param_sysfs_builtin_init+0x32/0x40 kernel/params.c:984
 do_one_initcall+0x236/0x820 init/main.c:1257
 do_initcall_level+0x137/0x1f0 init/main.c:1319
 do_initcalls+0x69/0xd0 init/main.c:1335
 kernel_init_freeable+0x3d9/0x570 init/main.c:1567
page_owner free stack trace missing

Memory state around the buggy address:
 ffff888031a12300: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff888031a12380: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff888031a12400: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                      ^
 ffff888031a12480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888031a12500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
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