KASAN: use-after-free Read in mousedev_cleanup

KASAN: use-after-free Read in mousedev_cleanup

[syzbot]

Hello,

syzbot found the following crash on:

HEAD commit:    c11d28ab Add linux-next specific files for 20200522
git tree:       linux-next
console output: https://syzkaller.appspot.com/x/log.txt?x=119c3f06100000
kernel config:  https://syzkaller.appspot.com/x/.config?x=3f6dbdea4159fb66
dashboard link: https://syzkaller.appspot.com/bug?extid=29b33f3f410e564731f1
compiler:       gcc (GCC) 9.0.0 20181231 (experimental)
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=135ffa9a100000
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=1076acba100000

The bug was bisected to:

commit 4ef12f7198023c09ad6d25b652bd8748c965c7fa
Author: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Date:   Wed May 13 15:18:40 2020 +0000

    kobject: Make sure the parent does not get released before its children

bisection log:  https://syzkaller.appspot.com/x/bisect.txt?x=14ab01e2100000
final crash:    https://syzkaller.appspot.com/x/report.txt?x=16ab01e2100000
console output: https://syzkaller.appspot.com/x/log.txt?x=12ab01e2100000

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+29b33f3f410e564731f1@syzkaller.appspotmail.com
Fixes: 4ef12f719802 ("kobject: Make sure the parent does not get released before its children")

usb 1-1: USB disconnect, device number 2
==================================================================
BUG: KASAN: use-after-free in __mutex_lock_common kernel/locking/mutex.c:938 [inline]
BUG: KASAN: use-after-free in __mutex_lock+0x1033/0x13c0 kernel/locking/mutex.c:1103
Read of size 8 at addr ffff88809452f150 by task kworker/0:2/2485

CPU: 0 PID: 2485 Comm: kworker/0:2 Not tainted 5.7.0-rc6-next-20200522-syzkaller #0
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+0x18f/0x20d lib/dump_stack.c:118
 print_address_description.constprop.0.cold+0xd3/0x413 mm/kasan/report.c:383
 __kasan_report mm/kasan/report.c:513 [inline]
 kasan_report.cold+0x1f/0x37 mm/kasan/report.c:530
 __mutex_lock_common kernel/locking/mutex.c:938 [inline]
 __mutex_lock+0x1033/0x13c0 kernel/locking/mutex.c:1103
 mousedev_mark_dead drivers/input/mousedev.c:791 [inline]
 mousedev_cleanup+0x21/0x180 drivers/input/mousedev.c:816
 mousedev_destroy+0x28/0xa0 drivers/input/mousedev.c:928
 __input_unregister_device+0x1b0/0x430 drivers/input/input.c:2091
 input_unregister_device+0xb4/0xf0 drivers/input/input.c:2273
 hidinput_disconnect+0x15e/0x3d0 drivers/hid/hid-input.c:1968
 hid_disconnect+0x13f/0x1a0 drivers/hid/hid-core.c:2008
 hid_hw_stop drivers/hid/hid-core.c:2055 [inline]
 hid_device_remove+0x186/0x240 drivers/hid/hid-core.c:2298
 __device_release_driver drivers/base/dd.c:1111 [inline]
 device_release_driver_internal+0x231/0x500 drivers/base/dd.c:1144
 bus_remove_device+0x2dc/0x4a0 drivers/base/bus.c:533
 device_del+0x481/0xd30 drivers/base/core.c:2839
 hid_remove_device drivers/hid/hid-core.c:2467 [inline]
 hid_destroy_device+0xe1/0x150 drivers/hid/hid-core.c:2486
 usbhid_disconnect+0x9f/0xe0 drivers/hid/usbhid/hid-core.c:1434
 usb_unbind_interface+0x1bd/0x8a0 drivers/usb/core/driver.c:436
 __device_release_driver drivers/base/dd.c:1113 [inline]
 device_release_driver_internal+0x432/0x500 drivers/base/dd.c:1144
 bus_remove_device+0x2dc/0x4a0 drivers/base/bus.c:533
 device_del+0x481/0xd30 drivers/base/core.c:2839
 usb_disable_device+0x211/0x690 drivers/usb/core/message.c:1245
 usb_disconnect+0x284/0x8d0 drivers/usb/core/hub.c:2217
 hub_port_connect drivers/usb/core/hub.c:5059 [inline]
 hub_port_connect_change drivers/usb/core/hub.c:5348 [inline]
 port_event drivers/usb/core/hub.c:5494 [inline]
 hub_event+0x17ca/0x38f0 drivers/usb/core/hub.c:5576
 process_one_work+0x965/0x16a0 kernel/workqueue.c:2268
 worker_thread+0x96/0xe20 kernel/workqueue.c:2414
 kthread+0x3b5/0x4a0 kernel/kthread.c:291
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:351

Allocated by task 17:
 save_stack+0x1b/0x40 mm/kasan/common.c:48
 set_track mm/kasan/common.c:56 [inline]
 __kasan_kmalloc mm/kasan/common.c:494 [inline]
 __kasan_kmalloc.constprop.0+0xbf/0xd0 mm/kasan/common.c:467
 kmem_cache_alloc_trace+0x153/0x7d0 mm/slab.c:3551
 kmalloc include/linux/slab.h:555 [inline]
 kzalloc include/linux/slab.h:669 [inline]
 mousedev_create+0x90/0xa20 drivers/input/mousedev.c:856
 mousedev_connect+0x20/0x280 drivers/input/mousedev.c:981
 input_attach_handler+0x194/0x200 drivers/input/input.c:1031
 input_register_device.cold+0xf5/0x246 drivers/input/input.c:2229
 hidinput_connect+0x4f8f/0xdb30 drivers/hid/hid-input.c:1935
 hid_connect+0x96b/0xbc0 drivers/hid/hid-core.c:1931
 hid_hw_start drivers/hid/hid-core.c:2035 [inline]
 hid_hw_start+0xa2/0x130 drivers/hid/hid-core.c:2026
 kye_probe+0x44/0x536 drivers/hid/hid-kye.c:713
 hid_device_probe+0x2be/0x3f0 drivers/hid/hid-core.c:2263
 really_probe+0x281/0x6d0 drivers/base/dd.c:525
 driver_probe_device+0xfe/0x1d0 drivers/base/dd.c:701
 __device_attach_driver+0x1c2/0x220 drivers/base/dd.c:807
 bus_for_each_drv+0x162/0x1e0 drivers/base/bus.c:431
 __device_attach+0x21a/0x360 drivers/base/dd.c:873
 bus_probe_device+0x1e4/0x290 drivers/base/bus.c:491
 device_add+0xaf1/0x1900 drivers/base/core.c:2662
 hid_add_device drivers/hid/hid-core.c:2419 [inline]
 hid_add_device+0x33c/0x9a0 drivers/hid/hid-core.c:2368
 usbhid_probe+0xac8/0xff0 drivers/hid/usbhid/hid-core.c:1407
 usb_probe_interface+0x305/0x7a0 drivers/usb/core/driver.c:374
 really_probe+0x281/0x6d0 drivers/base/dd.c:525
 driver_probe_device+0xfe/0x1d0 drivers/base/dd.c:701
 __device_attach_driver+0x1c2/0x220 drivers/base/dd.c:807
 bus_for_each_drv+0x162/0x1e0 drivers/base/bus.c:431
 __device_attach+0x21a/0x360 drivers/base/dd.c:873
 bus_probe_device+0x1e4/0x290 drivers/base/bus.c:491
 device_add+0xaf1/0x1900 drivers/base/core.c:2662
 usb_set_configuration+0xec5/0x1740 drivers/usb/core/message.c:2032
 usb_generic_driver_probe+0x9d/0xe0 drivers/usb/core/generic.c:241
 usb_probe_device+0xc6/0x1f0 drivers/usb/core/driver.c:272
 really_probe+0x281/0x6d0 drivers/base/dd.c:525
 driver_probe_device+0xfe/0x1d0 drivers/base/dd.c:701
 __device_attach_driver+0x1c2/0x220 drivers/base/dd.c:807
 bus_for_each_drv+0x162/0x1e0 drivers/base/bus.c:431
 __device_attach+0x21a/0x360 drivers/base/dd.c:873
 bus_probe_device+0x1e4/0x290 drivers/base/bus.c:491
 device_add+0xaf1/0x1900 drivers/base/core.c:2662
 usb_new_device.cold+0x753/0x103d drivers/usb/core/hub.c:2554
 hub_port_connect drivers/usb/core/hub.c:5208 [inline]
 hub_port_connect_change drivers/usb/core/hub.c:5348 [inline]
 port_event drivers/usb/core/hub.c:5494 [inline]
 hub_event+0x1eca/0x38f0 drivers/usb/core/hub.c:5576
 process_one_work+0x965/0x16a0 kernel/workqueue.c:2268
 worker_thread+0x96/0xe20 kernel/workqueue.c:2414
 kthread+0x3b5/0x4a0 kernel/kthread.c:291
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:351

Freed by task 2485:
 save_stack+0x1b/0x40 mm/kasan/common.c:48
 set_track mm/kasan/common.c:56 [inline]
 kasan_set_free_info mm/kasan/common.c:316 [inline]
 __kasan_slab_free+0xf7/0x140 mm/kasan/common.c:455
 __cache_free mm/slab.c:3426 [inline]
 kfree+0x109/0x2b0 mm/slab.c:3757
 device_release+0x71/0x200 drivers/base/core.c:1541
 kobject_cleanup lib/kobject.c:701 [inline]
 kobject_release lib/kobject.c:732 [inline]
 kref_put include/linux/kref.h:65 [inline]
 kobject_put+0x1c8/0x2f0 lib/kobject.c:749
 cdev_device_del+0x69/0x80 fs/char_dev.c:575
 mousedev_destroy+0x20/0xa0 drivers/input/mousedev.c:927
 __input_unregister_device+0x1b0/0x430 drivers/input/input.c:2091
 input_unregister_device+0xb4/0xf0 drivers/input/input.c:2273
 hidinput_disconnect+0x15e/0x3d0 drivers/hid/hid-input.c:1968
 hid_disconnect+0x13f/0x1a0 drivers/hid/hid-core.c:2008
 hid_hw_stop drivers/hid/hid-core.c:2055 [inline]
 hid_device_remove+0x186/0x240 drivers/hid/hid-core.c:2298
 __device_release_driver drivers/base/dd.c:1111 [inline]
 device_release_driver_internal+0x231/0x500 drivers/base/dd.c:1144
 bus_remove_device+0x2dc/0x4a0 drivers/base/bus.c:533
 device_del+0x481/0xd30 drivers/base/core.c:2839
 hid_remove_device drivers/hid/hid-core.c:2467 [inline]
 hid_destroy_device+0xe1/0x150 drivers/hid/hid-core.c:2486
 usbhid_disconnect+0x9f/0xe0 drivers/hid/usbhid/hid-core.c:1434
 usb_unbind_interface+0x1bd/0x8a0 drivers/usb/core/driver.c:436
 __device_release_driver drivers/base/dd.c:1113 [inline]
 device_release_driver_internal+0x432/0x500 drivers/base/dd.c:1144
 bus_remove_device+0x2dc/0x4a0 drivers/base/bus.c:533
 device_del+0x481/0xd30 drivers/base/core.c:2839
 usb_disable_device+0x211/0x690 drivers/usb/core/message.c:1245
 usb_disconnect+0x284/0x8d0 drivers/usb/core/hub.c:2217
 hub_port_connect drivers/usb/core/hub.c:5059 [inline]
 hub_port_connect_change drivers/usb/core/hub.c:5348 [inline]
 port_event drivers/usb/core/hub.c:5494 [inline]
 hub_event+0x17ca/0x38f0 drivers/usb/core/hub.c:5576
 process_one_work+0x965/0x16a0 kernel/workqueue.c:2268
 worker_thread+0x96/0xe20 kernel/workqueue.c:2414
 kthread+0x3b5/0x4a0 kernel/kthread.c:291
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:351

The buggy address belongs to the object at ffff88809452f000
 which belongs to the cache kmalloc-2k of size 2048
The buggy address is located 336 bytes inside of
 2048-byte region [ffff88809452f000, ffff88809452f800)
The buggy address belongs to the page:
page:ffffea0002514bc0 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0
flags: 0xfffe0000000200(slab)
raw: 00fffe0000000200 ffffea0002461788 ffffea0002786608 ffff8880aa000e00
raw: 0000000000000000 ffff88809452f000 0000000100000001 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff88809452f000: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88809452f080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff88809452f100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                                 ^
 ffff88809452f180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88809452f200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================


---
This bug is generated by a bot. It may contain errors.
See https://goo.gl/tpsmEJ for more information about syzbot.
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For information about bisection process see: https://goo.gl/tpsmEJ#bisection
syzbot can test patches for this bug, for details see:
https://goo.gl/tpsmEJ#testing-patches

Re: KASAN: use-after-free Read in mousedev_cleanup

[Eric Biggers]

On Sat, May 23, 2020 at 10:04:14AM -0700, syzbot wrote:
> Hello,
> 
> syzbot found the following crash on:
> 
> HEAD commit:    c11d28ab Add linux-next specific files for 20200522
> git tree:       linux-next
> console output: https://syzkaller.appspot.com/x/log.txt?x=119c3f06100000
> kernel config:  https://syzkaller.appspot.com/x/.config?x=3f6dbdea4159fb66
> dashboard link: https://syzkaller.appspot.com/bug?extid=29b33f3f410e564731f1
> compiler:       gcc (GCC) 9.0.0 20181231 (experimental)
> syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=135ffa9a100000
> C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=1076acba100000
> 
> The bug was bisected to:
> 
> commit 4ef12f7198023c09ad6d25b652bd8748c965c7fa
> Author: Heikki Krogerus <heikki.krogerus@linux.intel.com>
> Date:   Wed May 13 15:18:40 2020 +0000
> 
>     kobject: Make sure the parent does not get released before its children
> 

Commit was reverted.

#syz invalid