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BUG: KASAN: use-after-free in ds_probe+0x5ff/0x750 drivers/w1/masters/ds2490.c:1019
Read of size 1 at addr ffff8881d2191322 by task kworker/1:6/5847

CPU: 1 PID: 5847 Comm: kworker/1:6 Not tainted 5.1.0-rc3+ #8
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: usb_hub_wq hub_event
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0xca/0x13e lib/dump_stack.c:113
 print_address_description+0x67/0x231 mm/kasan/report.c:187
 kasan_report.cold+0x1a/0x35 mm/kasan/report.c:317
 ds_probe+0x5ff/0x750 drivers/w1/masters/ds2490.c:1019
 usb_probe_interface+0x30d/0x7b0 drivers/usb/core/driver.c:361
 really_probe+0x296/0x680 drivers/base/dd.c:509
 driver_probe_device+0xf9/0x200 drivers/base/dd.c:671
 __device_attach_driver+0x1c4/0x230 drivers/base/dd.c:778
 bus_for_each_drv+0x15e/0x1e0 drivers/base/bus.c:454
 __device_attach+0x21e/0x360 drivers/base/dd.c:844
 bus_probe_device+0x1ec/0x2a0 drivers/base/bus.c:514
 device_add+0xaf4/0x1700 drivers/base/core.c:2106
 usb_set_configuration+0xdf2/0x1670 drivers/usb/core/message.c:2023
 generic_probe+0x9d/0xd5 drivers/usb/core/generic.c:210
 usb_probe_device+0xa8/0x110 drivers/usb/core/driver.c:266
 really_probe+0x296/0x680 drivers/base/dd.c:509
 driver_probe_device+0xf9/0x200 drivers/base/dd.c:671
 __device_attach_driver+0x1c4/0x230 drivers/base/dd.c:778
 bus_for_each_drv+0x15e/0x1e0 drivers/base/bus.c:454
 __device_attach+0x21e/0x360 drivers/base/dd.c:844
 bus_probe_device+0x1ec/0x2a0 drivers/base/bus.c:514
 device_add+0xaf4/0x1700 drivers/base/core.c:2106
 usb_new_device.cold+0x8b8/0x1030 drivers/usb/core/hub.c:2534
 hub_port_connect drivers/usb/core/hub.c:5089 [inline]
 hub_port_connect_change drivers/usb/core/hub.c:5204 [inline]
 port_event drivers/usb/core/hub.c:5350 [inline]
 hub_event+0x1ac9/0x35a0 drivers/usb/core/hub.c:5432
 process_one_work+0x90a/0x1580 kernel/workqueue.c:2269
 process_scheduled_works kernel/workqueue.c:2331 [inline]
 worker_thread+0x7ab/0xe20 kernel/workqueue.c:2417
 kthread+0x30e/0x420 kernel/kthread.c:253
 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:352

Allocated by task 4646:
 set_track mm/kasan/common.c:87 [inline]
 __kasan_kmalloc mm/kasan/common.c:497 [inline]
 __kasan_kmalloc.constprop.0+0xbf/0xd0 mm/kasan/common.c:470
 kmalloc include/linux/slab.h:547 [inline]
 kzalloc include/linux/slab.h:742 [inline]
 ext4_htree_create_dir_info fs/ext4/dir.c:414 [inline]
 ext4_dx_readdir fs/ext4/dir.c:533 [inline]
 ext4_readdir+0x1b2b/0x2930 fs/ext4/dir.c:121
 iterate_dir+0x47c/0x5e0 fs/readdir.c:51
 __do_sys_getdents fs/readdir.c:231 [inline]
 __se_sys_getdents fs/readdir.c:212 [inline]
 __x64_sys_getdents+0x1dd/0x370 fs/readdir.c:212
 do_syscall_64+0xbd/0x500 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

Freed by task 4646:
 set_track mm/kasan/common.c:87 [inline]
 __kasan_slab_free+0x130/0x180 mm/kasan/common.c:459
 slab_free_hook mm/slub.c:1429 [inline]
 slab_free_freelist_hook mm/slub.c:1456 [inline]
 slab_free mm/slub.c:3003 [inline]
 kfree+0xd7/0x290 mm/slub.c:3958
 ext4_htree_free_dir_info fs/ext4/dir.c:425 [inline]
 ext4_release_dir+0x49/0x60 fs/ext4/dir.c:622
 __fput+0x2d2/0x7d0 fs/file_table.c:278
 task_work_run+0x144/0x1c0 kernel/task_work.c:113
 tracehook_notify_resume include/linux/tracehook.h:188 [inline]
 exit_to_usermode_loop+0x1c5/0x1f0 arch/x86/entry/common.c:166
 prepare_exit_to_usermode arch/x86/entry/common.c:197 [inline]
 syscall_return_slowpath arch/x86/entry/common.c:268 [inline]
 do_syscall_64+0x3ed/0x500 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

The buggy address belongs to the object at ffff8881d2191300
 which belongs to the cache kmalloc-64 of size 64
The buggy address is located 34 bytes inside of
 64-byte region [ffff8881d2191300, ffff8881d2191340)
The buggy address belongs to the page:
page:ffffea0007486440 count:1 mapcount:0 mapping:ffff8881dac03600 index:0x0
flags: 0x200000000000200(slab)
raw: 0200000000000200 ffffea0007450700 0000001200000012 ffff8881dac03600
raw: 0000000000000000 00000000002a002a 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8881d2191200: 00 00 fc fc fc fc fc fc fb fb fb fb fb fb fb fb
 ffff8881d2191280: fc fc fc fc 00 00 00 00 00 00 fc fc fc fc fc fc
>ffff8881d2191300: fb fb fb fb fb fb fb fb fc fc fc fc fb fb fb fb
                               ^
 ffff8881d2191380: fb fb fb fb fc fc fc fc fb fb fb fb fb fb fb fb
 ffff8881d2191400: fc fc fc fc fb fb fb fb fb fb fb fb fc fc fc fc
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