================================================================== BUG: KASAN: slab-use-after-free in hci_conn_hash_flush+0x244/0x270 net/bluetooth/hci_conn.c:2470 Read of size 8 at addr ffff888072376000 by task syz-executor296/5124 CPU: 0 PID: 5124 Comm: syz-executor296 Not tainted 6.3.0-syzkaller-07946-g281900a923d4 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/14/2023 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xd9/0x150 lib/dump_stack.c:106 print_address_description.constprop.0+0x2c/0x3c0 mm/kasan/report.c:319 print_report mm/kasan/report.c:430 [inline] kasan_report+0x11c/0x130 mm/kasan/report.c:536 hci_conn_hash_flush+0x244/0x270 net/bluetooth/hci_conn.c:2470 hci_dev_close_sync+0x5fb/0x1200 net/bluetooth/hci_sync.c:4941 hci_dev_do_close+0x31/0x70 net/bluetooth/hci_core.c:554 hci_unregister_dev+0x1ce/0x580 net/bluetooth/hci_core.c:2703 vhci_release+0x80/0xf0 drivers/bluetooth/hci_vhci.c:669 __fput+0x27c/0xa90 fs/file_table.c:321 task_work_run+0x16f/0x270 kernel/task_work.c:179 exit_task_work include/linux/task_work.h:38 [inline] do_exit+0xad3/0x2960 kernel/exit.c:869 do_group_exit+0xd4/0x2a0 kernel/exit.c:1019 get_signal+0x2315/0x25b0 kernel/signal.c:2874 arch_do_signal_or_restart+0x79/0x5c0 arch/x86/kernel/signal.c:306 exit_to_user_mode_loop kernel/entry/common.c:168 [inline] exit_to_user_mode_prepare+0x11f/0x240 kernel/entry/common.c:204 __syscall_exit_to_user_mode_work kernel/entry/common.c:286 [inline] syscall_exit_to_user_mode+0x1d/0x50 kernel/entry/common.c:297 do_syscall_64+0x46/0xb0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7f2776f3e1ed Code: Unable to access opcode bytes at 0x7f2776f3e1c3. RSP: 002b:00007fff533df430 EFLAGS: 00000246 ORIG_RAX: 000000000000009d RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00007f2776f3e1ed RDX: 0000000000000000 RSI: 0000000000000009 RDI: 0000000000000001 RBP: 0000000000000000 R08: 0000000000000000 R09: 00007f2776fbc150 R10: 0000000000000000 R11: 0000000000000246 R12: 00007fff533df4ac R13: 00007fff533df4c0 R14: 00007fff533df500 R15: 0000000000000020 Allocated by task 5036: kasan_save_stack+0x22/0x40 mm/kasan/common.c:45 kasan_set_track+0x25/0x30 mm/kasan/common.c:52 ____kasan_kmalloc mm/kasan/common.c:374 [inline] ____kasan_kmalloc mm/kasan/common.c:333 [inline] __kasan_kmalloc+0xa2/0xb0 mm/kasan/common.c:383 kmalloc include/linux/slab.h:560 [inline] kzalloc include/linux/slab.h:681 [inline] hci_conn_add+0xb8/0x16b0 net/bluetooth/hci_conn.c:986 hci_connect_sco+0x3c7/0x1050 net/bluetooth/hci_conn.c:1663 sco_connect net/bluetooth/sco.c:264 [inline] sco_sock_connect+0x2d7/0xae0 net/bluetooth/sco.c:610 __sys_connect_file+0x153/0x1a0 net/socket.c:2003 __sys_connect+0x165/0x1a0 net/socket.c:2020 __do_sys_connect net/socket.c:2030 [inline] __se_sys_connect net/socket.c:2027 [inline] __x64_sys_connect+0x73/0xb0 net/socket.c:2027 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd Freed by task 5124: kasan_save_stack+0x22/0x40 mm/kasan/common.c:45 kasan_set_track+0x25/0x30 mm/kasan/common.c:52 kasan_save_free_info+0x2e/0x40 mm/kasan/generic.c:521 ____kasan_slab_free mm/kasan/common.c:236 [inline] ____kasan_slab_free+0x160/0x1c0 mm/kasan/common.c:200 kasan_slab_free include/linux/kasan.h:162 [inline] slab_free_hook mm/slub.c:1781 [inline] slab_free_freelist_hook+0x8b/0x1c0 mm/slub.c:1807 slab_free mm/slub.c:3787 [inline] __kmem_cache_free+0xaf/0x2d0 mm/slub.c:3800 device_release+0xa3/0x240 drivers/base/core.c:2436 kobject_cleanup lib/kobject.c:681 [inline] kobject_release lib/kobject.c:712 [inline] kref_put include/linux/kref.h:65 [inline] kobject_put+0x1c2/0x4d0 lib/kobject.c:729 put_device+0x1f/0x30 drivers/base/core.c:3697 hci_conn_del+0x1e5/0x950 net/bluetooth/hci_conn.c:1162 hci_conn_unlink+0x2ce/0x460 net/bluetooth/hci_conn.c:1109 hci_conn_unlink+0x362/0x460 net/bluetooth/hci_conn.c:1087 hci_conn_hash_flush+0x19b/0x270 net/bluetooth/hci_conn.c:2479 hci_dev_close_sync+0x5fb/0x1200 net/bluetooth/hci_sync.c:4941 hci_dev_do_close+0x31/0x70 net/bluetooth/hci_core.c:554 hci_unregister_dev+0x1ce/0x580 net/bluetooth/hci_core.c:2703 vhci_release+0x80/0xf0 drivers/bluetooth/hci_vhci.c:669 __fput+0x27c/0xa90 fs/file_table.c:321 task_work_run+0x16f/0x270 kernel/task_work.c:179 exit_task_work include/linux/task_work.h:38 [inline] do_exit+0xad3/0x2960 kernel/exit.c:869 do_group_exit+0xd4/0x2a0 kernel/exit.c:1019 get_signal+0x2315/0x25b0 kernel/signal.c:2874 arch_do_signal_or_restart+0x79/0x5c0 arch/x86/kernel/signal.c:306 exit_to_user_mode_loop kernel/entry/common.c:168 [inline] exit_to_user_mode_prepare+0x11f/0x240 kernel/entry/common.c:204 __syscall_exit_to_user_mode_work kernel/entry/common.c:286 [inline] syscall_exit_to_user_mode+0x1d/0x50 kernel/entry/common.c:297 do_syscall_64+0x46/0xb0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x63/0xcd The buggy address belongs to the object at ffff888072376000 which belongs to the cache kmalloc-4k of size 4096 The buggy address is located 0 bytes inside of freed 4096-byte region [ffff888072376000, ffff888072377000) The buggy address belongs to the physical page: page:ffffea0001c8dc00 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x72370 head:ffffea0001c8dc00 order:3 entire_mapcount:0 nr_pages_mapped:0 pincount:0 flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000010200 ffff888012442140 dead000000000122 0000000000000000 raw: 0000000000000000 0000000000040004 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 3, migratetype Unmovable, gfp_mask 0x1d20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL), pid 5012, tgid 5012 (syz-executor296), ts 55814079197, free_ts 13850973918 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x2db/0x350 mm/page_alloc.c:2546 prep_new_page mm/page_alloc.c:2553 [inline] get_page_from_freelist+0x1190/0x2e20 mm/page_alloc.c:4326 __alloc_pages+0x1cb/0x4a0 mm/page_alloc.c:5592 alloc_pages+0x1aa/0x270 mm/mempolicy.c:2277 alloc_slab_page mm/slub.c:1851 [inline] allocate_slab+0x25f/0x390 mm/slub.c:1998 new_slab mm/slub.c:2051 [inline] ___slab_alloc+0xa91/0x1400 mm/slub.c:3193 __slab_alloc.constprop.0+0x56/0xa0 mm/slub.c:3292 __slab_alloc_node mm/slub.c:3345 [inline] slab_alloc_node mm/slub.c:3442 [inline] __kmem_cache_alloc_node+0x136/0x320 mm/slub.c:3491 __do_kmalloc_node mm/slab_common.c:965 [inline] __kmalloc+0x4e/0x190 mm/slab_common.c:979 kmalloc include/linux/slab.h:564 [inline] kzalloc include/linux/slab.h:681 [inline] cgroup_create kernel/cgroup/cgroup.c:5592 [inline] cgroup_mkdir+0x25c/0x10b0 kernel/cgroup/cgroup.c:5738 kernfs_iop_mkdir+0x14a/0x1d0 fs/kernfs/dir.c:1214 vfs_mkdir+0x242/0x460 fs/namei.c:4038 do_mkdirat+0x28d/0x310 fs/namei.c:4061 __do_sys_mkdir fs/namei.c:4081 [inline] __se_sys_mkdir fs/namei.c:4079 [inline] __x64_sys_mkdir+0xf6/0x140 fs/namei.c:4079 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1454 [inline] free_pcp_prepare+0x5da/0xa60 mm/page_alloc.c:1504 free_unref_page_prepare mm/page_alloc.c:3388 [inline] free_unref_page+0x1d/0x490 mm/page_alloc.c:3483 free_contig_range+0xb5/0x180 mm/page_alloc.c:9551 destroy_args+0x6c4/0x920 mm/debug_vm_pgtable.c:1023 debug_vm_pgtable+0x2412/0x4210 mm/debug_vm_pgtable.c:1403 do_one_initcall+0x102/0x540 init/main.c:1313 do_initcall_level init/main.c:1386 [inline] do_initcalls init/main.c:1402 [inline] do_basic_setup init/main.c:1421 [inline] kernel_init_freeable+0x696/0xc00 init/main.c:1641 kernel_init+0x1e/0x2c0 init/main.c:1529 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308 Memory state around the buggy address: ffff888072375f00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff888072375f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff888072376000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888072376080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888072376100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================