================================================================== BUG: KASAN: slab-use-after-free in instrument_atomic_read_write include/linux/instrumented.h:112 [inline] BUG: KASAN: slab-use-after-free in atomic_fetch_add_relaxed include/linux/atomic/atomic-instrumented.h:252 [inline] BUG: KASAN: slab-use-after-free in __refcount_add include/linux/refcount.h:283 [inline] BUG: KASAN: slab-use-after-free in __refcount_inc include/linux/refcount.h:366 [inline] BUG: KASAN: slab-use-after-free in refcount_inc include/linux/refcount.h:383 [inline] BUG: KASAN: slab-use-after-free in sock_hold include/net/sock.h:839 [inline] BUG: KASAN: slab-use-after-free in bt_accept_dequeue+0x6bd/0x920 net/bluetooth/af_bluetooth.c:348 Write of size 4 at addr ffff888056194080 by task syz.2.69/6079 CPU: 2 UID: 0 PID: 6079 Comm: syz.2.69 Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:378 [inline] print_report+0x13d/0x4b0 mm/kasan/report.c:482 kasan_report+0xdf/0x1c0 mm/kasan/report.c:595 check_region_inline mm/kasan/generic.c:186 [inline] kasan_check_range+0x10f/0x1e0 mm/kasan/generic.c:200 instrument_atomic_read_write include/linux/instrumented.h:112 [inline] atomic_fetch_add_relaxed include/linux/atomic/atomic-instrumented.h:252 [inline] __refcount_add include/linux/refcount.h:283 [inline] __refcount_inc include/linux/refcount.h:366 [inline] refcount_inc include/linux/refcount.h:383 [inline] sock_hold include/net/sock.h:839 [inline] bt_accept_dequeue+0x6bd/0x920 net/bluetooth/af_bluetooth.c:348 l2cap_sock_cleanup_listen+0x47/0x4d0 net/bluetooth/l2cap_sock.c:1517 l2cap_sock_release+0x69/0x280 net/bluetooth/l2cap_sock.c:1466 __sock_release+0xb3/0x260 net/socket.c:710 sock_close+0x1c/0x30 net/socket.c:1501 __fput+0x3ff/0xb50 fs/file_table.c:512 task_work_run+0x150/0x240 kernel/task_work.c:233 exit_task_work include/linux/task_work.h:40 [inline] do_exit+0x951/0x2ae0 kernel/exit.c:1004 do_group_exit+0xd5/0x2a0 kernel/exit.c:1147 get_signal+0x1ec7/0x21e0 kernel/signal.c:3038 arch_do_signal_or_restart+0x91/0x7e0 arch/x86/kernel/signal.c:337 __exit_to_user_mode_loop kernel/entry/common.c:66 [inline] exit_to_user_mode_loop+0x139/0x6f0 kernel/entry/common.c:101 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:207 [inline] syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:230 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:318 [inline] do_syscall_64+0x666/0x870 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: eccb:0xe4a421182f13d611 Code: Unable to access opcode bytes at 0xe4a421182f13d5e7. RSP: 002b:00007fe53b234f58 EFLAGS: 00000756 ORIG_RAX: d1d66dbfed01019b RAX: 2bf9e1987c1988ee RBX: 6f67a894836fe1f3 RCX: ed0b474b2b46640f RDX: fb381f0b5e12d2ce RSI: 401aaa756d8c34aa RDI: 30b9ec15aecde911 RBP: 532828f82bbb556c R08: dbce39d105fdbf88 R09: ae9ea378b9c9fbc7 R10: 33740f3b8630618c R11: 2450ade207355af5 R12: 0a61688f027fb1a4 R13: 339c71c774e61334 R14: 28baed4a0483d193 R15: 7c1f9cf2b758efdc Allocated by task 5091: kasan_save_stack+0x30/0x50 mm/kasan/common.c:57 kasan_save_track+0x14/0x30 mm/kasan/common.c:78 poison_kmalloc_redzone mm/kasan/common.c:398 [inline] __kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:415 kasan_kmalloc include/linux/kasan.h:263 [inline] __do_kmalloc_node mm/slub.c:5334 [inline] __kmalloc_noprof+0x302/0x840 mm/slub.c:5347 _kmalloc_noprof include/linux/slab.h:973 [inline] sk_prot_alloc+0x10b/0x2a0 net/core/sock.c:2252 sk_alloc+0x36/0xe80 net/core/sock.c:2308 bt_sock_alloc+0x3b/0x3c0 net/bluetooth/af_bluetooth.c:148 l2cap_sock_alloc.constprop.0+0x33/0x1e0 net/bluetooth/l2cap_sock.c:1983 l2cap_sock_new_connection_cb+0x10f/0x260 net/bluetooth/l2cap_sock.c:1562 l2cap_connect_cfm+0x4e2/0xf80 net/bluetooth/l2cap_core.c:7481 hci_connect_cfm include/net/bluetooth/hci_core.h:2136 [inline] hci_remote_features_evt+0x4f4/0x9b0 net/bluetooth/hci_event.c:3764 hci_event_func net/bluetooth/hci_event.c:7800 [inline] hci_event_packet+0x8e9/0xcd0 net/bluetooth/hci_event.c:7851 hci_rx_work+0x451/0xfc0 net/bluetooth/hci_core.c:4039 process_one_work+0xa23/0x1940 kernel/workqueue.c:3322 process_scheduled_works kernel/workqueue.c:3405 [inline] worker_thread+0x5ef/0xe50 kernel/workqueue.c:3486 kthread+0x370/0x450 kernel/kthread.c:436 ret_from_fork+0x72b/0xd50 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Freed by task 6079: kasan_save_stack+0x30/0x50 mm/kasan/common.c:57 kasan_save_track+0x14/0x30 mm/kasan/common.c:78 kasan_save_free_info+0x3b/0x70 mm/kasan/generic.c:584 poison_slab_object mm/kasan/common.c:253 [inline] __kasan_slab_free+0x5f/0x80 mm/kasan/common.c:285 kasan_slab_free include/linux/kasan.h:235 [inline] slab_free_hook mm/slub.c:2700 [inline] slab_free mm/slub.c:6310 [inline] kfree+0x22b/0x6c0 mm/slub.c:6625 sk_prot_free net/core/sock.c:2291 [inline] __sk_destruct+0x88c/0xab0 net/core/sock.c:2391 sk_destruct+0xc8/0xf0 net/core/sock.c:2419 __sk_free+0xf4/0x3e0 net/core/sock.c:2430 sk_free+0x61/0x90 net/core/sock.c:2441 sock_put include/net/sock.h:2020 [inline] bt_accept_unlink+0x22a/0x370 net/bluetooth/af_bluetooth.c:267 bt_accept_dequeue+0x791/0x920 net/bluetooth/af_bluetooth.c:336 l2cap_sock_cleanup_listen+0x47/0x4d0 net/bluetooth/l2cap_sock.c:1517 l2cap_sock_release+0x69/0x280 net/bluetooth/l2cap_sock.c:1466 __sock_release+0xb3/0x260 net/socket.c:710 sock_close+0x1c/0x30 net/socket.c:1501 __fput+0x3ff/0xb50 fs/file_table.c:512 task_work_run+0x150/0x240 kernel/task_work.c:233 exit_task_work include/linux/task_work.h:40 [inline] do_exit+0x951/0x2ae0 kernel/exit.c:1004 do_group_exit+0xd5/0x2a0 kernel/exit.c:1147 get_signal+0x1ec7/0x21e0 kernel/signal.c:3038 arch_do_signal_or_restart+0x91/0x7e0 arch/x86/kernel/signal.c:337 __exit_to_user_mode_loop kernel/entry/common.c:66 [inline] exit_to_user_mode_loop+0x139/0x6f0 kernel/entry/common.c:101 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:207 [inline] syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:230 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:318 [inline] do_syscall_64+0x666/0x870 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f The buggy address belongs to the object at ffff888056194000 which belongs to the cache kmalloc-2k of size 2048 The buggy address is located 128 bytes inside of freed 2048-byte region [ffff888056194000, ffff888056194800) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff888056190000 pfn:0x56190 head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 flags: 0xfff00000000240(workingset|head|node=0|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 00fff00000000240 ffff88801b842f00 ffffea00009b7410 ffffea0001611410 raw: ffff888056190000 0000000800080006 00000000f5000000 0000000000000000 head: 00fff00000000240 ffff88801b842f00 ffffea00009b7410 ffffea0001611410 head: ffff888056190000 0000000800080006 00000000f5000000 0000000000000000 head: 00fff00000000003 fffffffffffffe01 00000000ffffffff 00000000ffffffff head: ffffffffffffffff 0000000000000000 00000000ffffffff 0000000000000008 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 5732, tgid 5732 (syz-executor), ts 50710767444, free_ts 0 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0xfd/0x120 mm/page_alloc.c:1853 prep_new_page mm/page_alloc.c:1861 [inline] get_page_from_freelist+0x812/0x3d20 mm/page_alloc.c:3941 __alloc_frozen_pages_noprof+0x27c/0x2b60 mm/page_alloc.c:5221 alloc_slab_page mm/slub.c:3289 [inline] allocate_slab mm/slub.c:3404 [inline] new_slab+0xa2/0x670 mm/slub.c:3447 refill_objects+0xe3/0x430 mm/slub.c:7241 refill_sheaf mm/slub.c:2827 [inline] __pcs_replace_empty_main+0x375/0x660 mm/slub.c:4692 alloc_from_pcs mm/slub.c:4790 [inline] slab_alloc_node mm/slub.c:4924 [inline] __kmalloc_cache_noprof+0x48d/0x6e0 mm/slub.c:5446 _kmalloc_noprof include/linux/slab.h:969 [inline] rtnl_newlink+0x126/0x2380 net/core/rtnetlink.c:4051 rtnetlink_rcv_msg+0x95e/0xe90 net/core/rtnetlink.c:7068 netlink_rcv_skb+0x159/0x420 net/netlink/af_netlink.c:2556 netlink_unicast_kernel net/netlink/af_netlink.c:1319 [inline] netlink_unicast+0x585/0x850 net/netlink/af_netlink.c:1345 netlink_sendmsg+0x8b0/0xda0 net/netlink/af_netlink.c:1900 sock_sendmsg_nosec net/socket.c:775 [inline] __sock_sendmsg net/socket.c:790 [inline] __sys_sendto+0x452/0x4a0 net/socket.c:2252 __do_sys_sendto net/socket.c:2259 [inline] __se_sys_sendto net/socket.c:2255 [inline] __x64_sys_sendto+0xe0/0x1c0 net/socket.c:2255 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x115/0x870 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f page_owner free stack trace missing Memory state around the buggy address: ffff888056193f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff888056194000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff888056194080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888056194100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888056194180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================