================================================================== BUG: KASAN: use-after-free in atomic_inc include/asm-generic/atomic-instrumented.h:109 [inline] BUG: KASAN: use-after-free in hci_sock_bind+0x521/0x1000 net/bluetooth/hci_sock.c:1226 Write of size 4 at addr ffff88807e286860 by task syz-executor.0/18602 CPU: 0 PID: 18602 Comm: syz-executor.0 Not tainted 4.19.113-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x188/0x20d lib/dump_stack.c:118 print_address_description.cold+0x7c/0x212 mm/kasan/report.c:256 kasan_report_error mm/kasan/report.c:354 [inline] kasan_report mm/kasan/report.c:412 [inline] kasan_report.cold+0x88/0x2b9 mm/kasan/report.c:396 atomic_inc include/asm-generic/atomic-instrumented.h:109 [inline] hci_sock_bind+0x521/0x1000 net/bluetooth/hci_sock.c:1226 __sys_bind+0x20e/0x250 net/socket.c:1482 __do_sys_bind net/socket.c:1493 [inline] __se_sys_bind net/socket.c:1491 [inline] __x64_sys_bind+0x6f/0xb0 net/socket.c:1491 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x45c849 Code: ad b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 7b b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f2b41c02c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000031 RAX: ffffffffffffffda RBX: 00007f2b41c036d4 RCX: 000000000045c849 RDX: 0000000000000006 RSI: 0000000020000080 RDI: 0000000000000006 RBP: 000000000076bf00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 000000000000002c R14: 00000000004c2ce6 R15: 000000000076bf0c Allocated by task 18602: set_track mm/kasan/kasan.c:460 [inline] kasan_kmalloc mm/kasan/kasan.c:553 [inline] kasan_kmalloc+0xbf/0xe0 mm/kasan/kasan.c:531 kmem_cache_alloc_trace+0x14d/0x7a0 mm/slab.c:3625 kmalloc include/linux/slab.h:515 [inline] kzalloc include/linux/slab.h:709 [inline] hci_alloc_dev+0x3e/0x1cf0 net/bluetooth/hci_core.c:3053 __vhci_create_device+0x100/0x580 drivers/bluetooth/hci_vhci.c:114 vhci_create_device drivers/bluetooth/hci_vhci.c:163 [inline] vhci_get_user drivers/bluetooth/hci_vhci.c:219 [inline] vhci_write+0x2c5/0x460 drivers/bluetooth/hci_vhci.c:299 call_write_iter include/linux/fs.h:1821 [inline] new_sync_write fs/read_write.c:474 [inline] __vfs_write+0x512/0x760 fs/read_write.c:487 vfs_write+0x206/0x550 fs/read_write.c:549 ksys_write+0x12b/0x2a0 fs/read_write.c:599 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe Freed by task 18613: set_track mm/kasan/kasan.c:460 [inline] __kasan_slab_free+0xf7/0x140 mm/kasan/kasan.c:521 __cache_free mm/slab.c:3503 [inline] kfree+0xce/0x220 mm/slab.c:3822 bt_host_release+0x15/0x20 net/bluetooth/hci_sysfs.c:86 device_release+0x76/0x210 drivers/base/core.c:1061 kobject_cleanup lib/kobject.c:662 [inline] kobject_release lib/kobject.c:691 [inline] kref_put include/linux/kref.h:70 [inline] kobject_put+0x17c/0x270 lib/kobject.c:708 put_device+0x1c/0x30 drivers/base/core.c:2251 vhci_release+0x78/0xe0 drivers/bluetooth/hci_vhci.c:355 __fput+0x2cd/0x890 fs/file_table.c:278 task_work_run+0x13f/0x1b0 kernel/task_work.c:113 tracehook_notify_resume include/linux/tracehook.h:193 [inline] exit_to_usermode_loop+0x25a/0x2b0 arch/x86/entry/common.c:167 prepare_exit_to_usermode arch/x86/entry/common.c:198 [inline] syscall_return_slowpath arch/x86/entry/common.c:271 [inline] do_syscall_64+0x538/0x620 arch/x86/entry/common.c:296 entry_SYSCALL_64_after_hwframe+0x49/0xbe The buggy address belongs to the object at ffff88807e285800 which belongs to the cache kmalloc-8192 of size 8192 The buggy address is located 4192 bytes inside of 8192-byte region [ffff88807e285800, ffff88807e287800) The buggy address belongs to the page: page:ffffea0001f8a100 count:1 mapcount:0 mapping:ffff88812c3d5080 index:0x0 compound_mapcount: 0 flags: 0xfffe0000008100(slab|head) raw: 00fffe0000008100 ffffea0000588708 ffffea00013b3f08 ffff88812c3d5080 raw: 0000000000000000 ffff88807e285800 0000000100000001 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff88807e286700: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88807e286780: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88807e286800: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88807e286880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88807e286900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== audit: type=1800 audit(1585716655.402:61): pid=18629 uid=0 auid=4294967295 ses=4294967295 subj=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 op=collect_data cause=failed(directio) comm="syz-executor.2" name="bus" dev="sda1" ino=16593 res=0