================================================================== 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 ffff888011f52408 by task syz-executor/5971 CPU: 0 UID: 0 PID: 5971 Comm: syz-executor Not tainted 6.14.0-rc5-syzkaller-01199-ge016cf5f39e9 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:408 [inline] print_report+0x16e/0x5b0 mm/kasan/report.c:521 kasan_report+0x143/0x180 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+0x878/0xab0 drivers/android/binderfs.c:210 binderfs_fill_super+0x96e/0xe70 drivers/android/binderfs.c:729 vfs_get_super fs/super.c:1280 [inline] get_tree_nodev+0xb7/0x140 fs/super.c:1299 vfs_get_tree+0x90/0x2b0 fs/super.c:1814 do_new_mount+0x2be/0xb40 fs/namespace.c:3560 do_mount fs/namespace.c:3900 [inline] __do_sys_mount fs/namespace.c:4111 [inline] __se_sys_mount+0x2d6/0x3c0 fs/namespace.c:4088 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fc8cbf8e90a 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:00007ffe456b6828 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 00007fc8cc00e663 RCX: 00007fc8cbf8e90a RDX: 00007fc8cc01dda7 RSI: 00007fc8cc00e663 RDI: 00007fc8cc01dda7 RBP: 00007fc8cc00e8ac R08: 0000000000000000 R09: 00007ffe456b68d0 R10: 0000000000000000 R11: 0000000000000246 R12: 00007fc8cbfeb1a8 R13: 00007fc8cbfeb180 R14: 0000000000000009 R15: 0000000000000000 Allocated by task 5830: 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:377 [inline] __kasan_kmalloc+0x98/0xb0 mm/kasan/common.c:394 kasan_kmalloc include/linux/kasan.h:260 [inline] __kmalloc_cache_noprof+0x243/0x390 mm/slub.c:4325 kmalloc_noprof include/linux/slab.h:901 [inline] kzalloc_noprof include/linux/slab.h:1037 [inline] binderfs_binder_device_create+0x171/0xab0 drivers/android/binderfs.c:147 binderfs_fill_super+0x96e/0xe70 drivers/android/binderfs.c:729 vfs_get_super fs/super.c:1280 [inline] get_tree_nodev+0xb7/0x140 fs/super.c:1299 vfs_get_tree+0x90/0x2b0 fs/super.c:1814 do_new_mount+0x2be/0xb40 fs/namespace.c:3560 do_mount fs/namespace.c:3900 [inline] __do_sys_mount fs/namespace.c:4111 [inline] __se_sys_mount+0x2d6/0x3c0 fs/namespace.c:4088 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f Freed by task 5830: 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:576 poison_slab_object mm/kasan/common.c:247 [inline] __kasan_slab_free+0x59/0x70 mm/kasan/common.c:264 kasan_slab_free include/linux/kasan.h:233 [inline] slab_free_hook mm/slub.c:2353 [inline] slab_free mm/slub.c:4609 [inline] kfree+0x196/0x430 mm/slub.c:4757 evict+0x4e8/0x9a0 fs/inode.c:796 __dentry_kill+0x20d/0x630 fs/dcache.c:643 shrink_kill+0xa9/0x2c0 fs/dcache.c:1088 shrink_dentry_list+0x2c0/0x5b0 fs/dcache.c:1115 shrink_dcache_parent+0xcb/0x3b0 do_one_tree+0x23/0xe0 fs/dcache.c:1578 shrink_dcache_for_umount+0xb4/0x180 fs/dcache.c:1595 generic_shutdown_super+0x6a/0x2d0 fs/super.c:620 kill_anon_super fs/super.c:1237 [inline] kill_litter_super+0x76/0xb0 fs/super.c:1247 binderfs_kill_super+0x44/0x90 drivers/android/binderfs.c:791 deactivate_locked_super+0xc4/0x130 fs/super.c:473 cleanup_mnt+0x41f/0x4b0 fs/namespace.c:1413 task_work_run+0x24f/0x310 kernel/task_work.c:227 exit_task_work include/linux/task_work.h:40 [inline] do_exit+0xa2a/0x28e0 kernel/exit.c:938 do_group_exit+0x207/0x2c0 kernel/exit.c:1087 get_signal+0x168c/0x1720 kernel/signal.c:3036 arch_do_signal_or_restart+0x96/0x860 arch/x86/kernel/signal.c:337 exit_to_user_mode_loop kernel/entry/common.c:111 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:329 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline] syscall_exit_to_user_mode+0xce/0x340 kernel/entry/common.c:218 do_syscall_64+0x100/0x230 arch/x86/entry/common.c:89 entry_SYSCALL_64_after_hwframe+0x77/0x7f The buggy address belongs to the object at ffff888011f52400 which belongs to the cache kmalloc-512 of size 512 The buggy address is located 8 bytes inside of freed 512-byte region [ffff888011f52400, ffff888011f52600) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x11f50 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 ffff88801b041c80 dead000000000122 0000000000000000 raw: 0000000000000000 0000000000100010 00000000f5000000 0000000000000000 head: 00fff00000000040 ffff88801b041c80 dead000000000122 0000000000000000 head: 0000000000000000 0000000000100010 00000000f5000000 0000000000000000 head: 00fff00000000002 ffffea000047d401 ffffffffffffffff 0000000000000000 head: ffff888000000004 0000000000000000 00000000ffffffff 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 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 5830, tgid 5830 (syz-executor), ts 57055050507, free_ts 57040139973 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x1f4/0x240 mm/page_alloc.c:1551 prep_new_page mm/page_alloc.c:1559 [inline] get_page_from_freelist+0x365c/0x37a0 mm/page_alloc.c:3477 __alloc_frozen_pages_noprof+0x292/0x710 mm/page_alloc.c:4739 alloc_pages_mpol+0x311/0x660 mm/mempolicy.c:2270 alloc_slab_page mm/slub.c:2423 [inline] allocate_slab+0x8f/0x3a0 mm/slub.c:2587 new_slab mm/slub.c:2640 [inline] ___slab_alloc+0xc27/0x14a0 mm/slub.c:3826 __slab_alloc+0x58/0xa0 mm/slub.c:3916 __slab_alloc_node mm/slub.c:3991 [inline] slab_alloc_node mm/slub.c:4152 [inline] __kmalloc_cache_noprof+0x27b/0x390 mm/slub.c:4320 kmalloc_noprof include/linux/slab.h:901 [inline] kzalloc_noprof include/linux/slab.h:1037 [inline] rxrpc_alloc_peer+0x7f/0x330 net/rxrpc/peer_object.c:230 rxrpc_service_prealloc_one+0x1d0/0xd60 net/rxrpc/call_accept.c:74 rxrpc_kernel_charge_accept+0xd2/0x100 net/rxrpc/call_accept.c:475 afs_charge_preallocation+0xba/0x2c0 fs/afs/rxrpc.c:739 afs_open_socket+0x46a/0x600 fs/afs/rxrpc.c:95 afs_net_init+0x7b9/0x9a0 fs/afs/main.c:123 ops_init+0x349/0x5b0 net/core/net_namespace.c:138 setup_net+0x287/0x9e0 net/core/net_namespace.c:362 page last free pid 5204 tgid 5204 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1127 [inline] free_frozen_pages+0xe0d/0x10e0 mm/page_alloc.c:2660 discard_slab mm/slub.c:2684 [inline] __put_partials+0x160/0x1c0 mm/slub.c:3153 put_cpu_partial+0x17c/0x250 mm/slub.c:3228 __slab_free+0x290/0x380 mm/slub.c:4479 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x9a/0x140 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x14f/0x170 mm/kasan/quarantine.c:286 __kasan_slab_alloc+0x23/0x80 mm/kasan/common.c:329 kasan_slab_alloc include/linux/kasan.h:250 [inline] slab_post_alloc_hook mm/slub.c:4115 [inline] slab_alloc_node mm/slub.c:4164 [inline] kmem_cache_alloc_noprof+0x1d9/0x380 mm/slub.c:4171 getname_flags+0xb7/0x540 fs/namei.c:139 do_sys_openat2+0xd2/0x1d0 fs/open.c:1422 do_sys_open fs/open.c:1443 [inline] __do_sys_openat fs/open.c:1459 [inline] __se_sys_openat fs/open.c:1454 [inline] __x64_sys_openat+0x247/0x2a0 fs/open.c:1454 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f Memory state around the buggy address: ffff888011f52300: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff888011f52380: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff888011f52400: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888011f52480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888011f52500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================