syzbot

 sign-in | mailing list | source | docs
🐞 Open [977] ≡ Subsystems 🐞 Fixed [5235] 🐞 Invalid [12492] ⬇ Missing Backports [83] 📈 Kernel Health 📈 Bug Lifetimes 📈 Fuzzing 📈 Crashes 💬 Send us feedback

KASAN: use-after-free Read in adu_disconnect

Status: fixed on 2019/10/27 22:28
Subsystems: usb
[Documentation on labels]
Reported-by: syzbot+0243cb250a51eeefb8cc@syzkaller.appspotmail.com
Fix commit: 44efc269db79 USB: adutux: fix use-after-free on disconnect
First crash: 1725d, last: 1652d
▶ ▼ Duplicate bugs (1)
duplicates (1):
Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
KMSAN: uninit-value in adu_disconnect usb C 13 1662d 1666d 0/26 closed as dup on 2019/10/04 00:50
▶ ▼ Discussions (11)
Title Replies (including bot) Last reply
[PATCH 4.19 00/81] 4.19.80-stable review 104 (104) 2020/09/24 13:54
[PATCH 3.16 00/72] 3.16.79-rc1 review 87 (87) 2019/12/14 18:44
[PATCH 5.3 000/112] 5.3.7-stable review 130 (130) 2019/10/18 10:12
[PATCH 4.14 00/65] 4.14.150-stable review 73 (73) 2019/10/18 09:59
[PATCH 4.9 00/92] 4.9.197-stable review 98 (98) 2019/10/18 07:56
[PATCH 4.4 00/79] 4.4.197-stable review 86 (86) 2019/10/18 07:55
Reminder: 67 active syzbot reports in usb subsystem 1 (1) 2019/10/04 03:38
[PATCH 1/2] USB: adutux: fix use-after-free on disconnect 2 (2) 2019/09/25 09:29
KASAN: use-after-free Read in adu_disconnect 13 (20) 2019/09/20 14:58
Reminder: 52 active syzbot reports in usb subsystem 4 (4) 2019/09/19 19:01
Reminder: 52 active syzbot reports in usb subsystem 1 (1) 2019/08/22 03:28
▶ ▼ Last patch testing requests (6)
Created Duration User Patch Repo Result
2019/09/20 14:38 18m johan@kernel.org patch https://github.com/google/kasan.git e0bd8d79 OK
2019/09/20 10:02 17m johan@kernel.org patch https://github.com/google/kasan.git e96407b4 report log
2019/09/20 09:08 11m johan@kernel.org patch https://github.com/google/kasan.git e96407b4 report log
2019/09/20 08:26 11m johan@kernel.org https://github.com/google/kasan.git e96407b4 report log
2019/09/19 10:35 17m johan@kernel.org patch https://github.com/google/kasan.git f0df5c1b OK
2019/09/18 17:02 10m linux.bhar@gmail.com patch https://github.com/google/kasan.git e96407b4 report log

Sample crash report:
usb 1-1: USB disconnect, device number 19
==================================================================
BUG: KASAN: use-after-free in atomic64_read include/asm-generic/atomic-instrumented.h:836 [inline]
BUG: KASAN: use-after-free in atomic_long_read include/asm-generic/atomic-long.h:28 [inline]
BUG: KASAN: use-after-free in __mutex_unlock_slowpath+0x96/0x670 kernel/locking/mutex.c:1237
Read of size 8 at addr ffff8881d201cc80 by task kworker/1:2/83

CPU: 1 PID: 83 Comm: kworker/1:2 Not tainted 5.3.0+ #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+0xca/0x13e lib/dump_stack.c:113
 print_address_description.constprop.0+0x36/0x50 mm/kasan/report.c:374
 __kasan_report.cold+0x1a/0x33 mm/kasan/report.c:506
 kasan_report+0xe/0x12 mm/kasan/common.c:634
 check_memory_region_inline mm/kasan/generic.c:185 [inline]
 check_memory_region+0x128/0x190 mm/kasan/generic.c:192
 atomic64_read include/asm-generic/atomic-instrumented.h:836 [inline]
 atomic_long_read include/asm-generic/atomic-long.h:28 [inline]
 __mutex_unlock_slowpath+0x96/0x670 kernel/locking/mutex.c:1237
 adu_disconnect+0x83/0x150 drivers/usb/misc/adutux.c:768
 usb_unbind_interface+0x1bd/0x8a0 drivers/usb/core/driver.c:423
 __device_release_driver drivers/base/dd.c:1134 [inline]
 device_release_driver_internal+0x42f/0x500 drivers/base/dd.c:1165
 bus_remove_device+0x2dc/0x4a0 drivers/base/bus.c:532
 device_del+0x420/0xb10 drivers/base/core.c:2375
 usb_disable_device+0x211/0x690 drivers/usb/core/message.c:1237
 usb_disconnect+0x284/0x8d0 drivers/usb/core/hub.c:2199
 hub_port_connect drivers/usb/core/hub.c:4949 [inline]
 hub_port_connect_change drivers/usb/core/hub.c:5213 [inline]
 port_event drivers/usb/core/hub.c:5359 [inline]
 hub_event+0x1454/0x3640 drivers/usb/core/hub.c:5441
 process_one_work+0x92b/0x1530 kernel/workqueue.c:2269
 worker_thread+0x96/0xe20 kernel/workqueue.c:2415
 kthread+0x318/0x420 kernel/kthread.c:255
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352

Allocated by task 12:
 save_stack+0x1b/0x80 mm/kasan/common.c:69
 set_track mm/kasan/common.c:77 [inline]
 __kasan_kmalloc mm/kasan/common.c:510 [inline]
 __kasan_kmalloc.constprop.0+0xbf/0xd0 mm/kasan/common.c:483
 kmalloc include/linux/slab.h:552 [inline]
 kzalloc include/linux/slab.h:686 [inline]
 adu_probe+0x7d/0x6e0 drivers/usb/misc/adutux.c:660
 usb_probe_interface+0x305/0x7a0 drivers/usb/core/driver.c:361
 really_probe+0x281/0x6d0 drivers/base/dd.c:548
 driver_probe_device+0x104/0x210 drivers/base/dd.c:721
 __device_attach_driver+0x1c2/0x220 drivers/base/dd.c:828
 bus_for_each_drv+0x162/0x1e0 drivers/base/bus.c:430
 __device_attach+0x217/0x360 drivers/base/dd.c:894
 bus_probe_device+0x1e4/0x290 drivers/base/bus.c:490
 device_add+0xae6/0x16f0 drivers/base/core.c:2201
 usb_set_configuration+0xdf6/0x1670 drivers/usb/core/message.c:2023
 generic_probe+0x9d/0xd5 drivers/usb/core/generic.c:210
 usb_probe_device+0x99/0x100 drivers/usb/core/driver.c:266
 really_probe+0x281/0x6d0 drivers/base/dd.c:548
 driver_probe_device+0x104/0x210 drivers/base/dd.c:721
 __device_attach_driver+0x1c2/0x220 drivers/base/dd.c:828
 bus_for_each_drv+0x162/0x1e0 drivers/base/bus.c:430
 __device_attach+0x217/0x360 drivers/base/dd.c:894
 bus_probe_device+0x1e4/0x290 drivers/base/bus.c:490
 device_add+0xae6/0x16f0 drivers/base/core.c:2201
 usb_new_device.cold+0x6a4/0xe79 drivers/usb/core/hub.c:2536
 hub_port_connect drivers/usb/core/hub.c:5098 [inline]
 hub_port_connect_change drivers/usb/core/hub.c:5213 [inline]
 port_event drivers/usb/core/hub.c:5359 [inline]
 hub_event+0x1b5c/0x3640 drivers/usb/core/hub.c:5441
 process_one_work+0x92b/0x1530 kernel/workqueue.c:2269
 worker_thread+0x96/0xe20 kernel/workqueue.c:2415
 kthread+0x318/0x420 kernel/kthread.c:255
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352

Freed by task 1767:
 save_stack+0x1b/0x80 mm/kasan/common.c:69
 set_track mm/kasan/common.c:77 [inline]
 kasan_set_free_info mm/kasan/common.c:332 [inline]
 __kasan_slab_free+0x130/0x180 mm/kasan/common.c:471
 slab_free_hook mm/slub.c:1424 [inline]
 slab_free_freelist_hook mm/slub.c:1475 [inline]
 slab_free mm/slub.c:3018 [inline]
 kfree+0xe4/0x2f0 mm/slub.c:3959
 adu_release+0x3cc/0x590 drivers/usb/misc/adutux.c:332
 __fput+0x2d7/0x840 fs/file_table.c:280
 task_work_run+0x13f/0x1c0 kernel/task_work.c:113
 tracehook_notify_resume include/linux/tracehook.h:188 [inline]
 exit_to_usermode_loop+0x1d2/0x200 arch/x86/entry/common.c:163
 prepare_exit_to_usermode arch/x86/entry/common.c:194 [inline]
 syscall_return_slowpath arch/x86/entry/common.c:274 [inline]
 do_syscall_64+0x45f/0x580 arch/x86/entry/common.c:300
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

The buggy address belongs to the object at ffff8881d201cc80
 which belongs to the cache kmalloc-512 of size 512
The buggy address is located 0 bytes inside of
 512-byte region [ffff8881d201cc80, ffff8881d201ce80)
The buggy address belongs to the page:
page:ffffea0007480700 refcount:1 mapcount:0 mapping:ffff8881da002500 index:0x0 compound_mapcount: 0
flags: 0x200000000010200(slab|head)
raw: 0200000000010200 0000000000000000 0000000900000001 ffff8881da002500
raw: 0000000000000000 00000000000c000c 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8881d201cb80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff8881d201cc00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff8881d201cc80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                   ^
 ffff8881d201cd00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff8881d201cd80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================

Crashes (5304):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2019/09/29 23:19 https://github.com/google/kasan.git usb-fuzzer 2994c07743fe c1ad5441 .config console log report syz C ci2-upstream-usb
2019/09/27 00:01 https://github.com/google/kasan.git usb-fuzzer 2994c07743fe 2f1548bc .config console log report syz C ci2-upstream-usb
2019/09/21 03:00 https://github.com/google/kasan.git usb-fuzzer e0bd8d794fc9 d96e88f3 .config console log report syz C ci2-upstream-usb
2019/08/22 00:36 https://github.com/google/kasan.git usb-fuzzer eea39f24f4a5 4ea67ff8 .config console log report syz C ci2-upstream-usb
2019/08/09 20:23 https://github.com/google/kasan.git usb-fuzzer e96407b49762 aff9e255 .config console log report syz C ci2-upstream-usb
2019/10/14 11:34 https://github.com/google/kasan.git usb-fuzzer 58d5f26a5584 a6aef847 .config console log report ci2-upstream-usb
2019/10/14 11:21 https://github.com/google/kasan.git usb-fuzzer 58d5f26a5584 a6aef847 .config console log report ci2-upstream-usb
2019/10/14 10:19 https://github.com/google/kasan.git usb-fuzzer 58d5f26a5584 a6aef847 .config console log report ci2-upstream-usb
2019/10/14 09:12 https://github.com/google/kasan.git usb-fuzzer 58d5f26a5584 2f661ec4 .config console log report ci2-upstream-usb
2019/10/14 07:54 https://github.com/google/kasan.git usb-fuzzer 58d5f26a5584 2f661ec4 .config console log report ci2-upstream-usb
2019/10/14 06:37 https://github.com/google/kasan.git usb-fuzzer 58d5f26a5584 2f661ec4 .config console log report ci2-upstream-usb
2019/10/14 05:21 https://github.com/google/kasan.git usb-fuzzer 58d5f26a5584 2f661ec4 .config console log report ci2-upstream-usb
2019/10/14 03:38 https://github.com/google/kasan.git usb-fuzzer 58d5f26a5584 2f661ec4 .config console log report ci2-upstream-usb
2019/10/14 02:32 https://github.com/google/kasan.git usb-fuzzer 58d5f26a5584 2f661ec4 .config console log report ci2-upstream-usb
2019/10/14 00:47 https://github.com/google/kasan.git usb-fuzzer 58d5f26a5584 2f661ec4 .config console log report ci2-upstream-usb
2019/10/13 23:42 https://github.com/google/kasan.git usb-fuzzer 58d5f26a5584 2f661ec4 .config console log report ci2-upstream-usb
2019/10/13 22:20 https://github.com/google/kasan.git usb-fuzzer 58d5f26a5584 2f661ec4 .config console log report ci2-upstream-usb
2019/10/13 20:59 https://github.com/google/kasan.git usb-fuzzer 58d5f26a5584 2f661ec4 .config console log report ci2-upstream-usb
2019/10/13 19:55 https://github.com/google/kasan.git usb-fuzzer 58d5f26a5584 2f661ec4 .config console log report ci2-upstream-usb
2019/10/13 18:51 https://github.com/google/kasan.git usb-fuzzer 58d5f26a5584 2f661ec4 .config console log report ci2-upstream-usb
2019/10/13 18:16 https://github.com/google/kasan.git usb-fuzzer 58d5f26a5584 2f661ec4 .config console log report ci2-upstream-usb
2019/10/13 17:07 https://github.com/google/kasan.git usb-fuzzer 58d5f26a5584 2f661ec4 .config console log report ci2-upstream-usb
2019/10/13 16:01 https://github.com/google/kasan.git usb-fuzzer 58d5f26a5584 2f661ec4 .config console log report ci2-upstream-usb
2019/10/13 14:58 https://github.com/google/kasan.git usb-fuzzer 58d5f26a5584 2f661ec4 .config console log report ci2-upstream-usb
2019/10/13 13:25 https://github.com/google/kasan.git usb-fuzzer 58d5f26a5584 2f661ec4 .config console log report ci2-upstream-usb
2019/10/13 12:28 https://github.com/google/kasan.git usb-fuzzer 58d5f26a5584 2f661ec4 .config console log report ci2-upstream-usb
2019/10/13 11:05 https://github.com/google/kasan.git usb-fuzzer 58d5f26a5584 2f661ec4 .config console log report ci2-upstream-usb
2019/10/13 09:56 https://github.com/google/kasan.git usb-fuzzer 58d5f26a5584 2f661ec4 .config console log report ci2-upstream-usb
2019/10/13 08:41 https://github.com/google/kasan.git usb-fuzzer 58d5f26a5584 2f661ec4 .config console log report ci2-upstream-usb
2019/10/13 07:26 https://github.com/google/kasan.git usb-fuzzer 58d5f26a5584 426631dd .config console log report ci2-upstream-usb
2019/10/13 05:33 https://github.com/google/kasan.git usb-fuzzer 58d5f26a5584 426631dd .config console log report ci2-upstream-usb
2019/10/13 05:17 https://github.com/google/kasan.git usb-fuzzer 58d5f26a5584 426631dd .config console log report ci2-upstream-usb
2019/10/13 04:13 https://github.com/google/kasan.git usb-fuzzer 58d5f26a5584 426631dd .config console log report ci2-upstream-usb
2019/10/13 02:37 https://github.com/google/kasan.git usb-fuzzer 58d5f26a5584 426631dd .config console log report ci2-upstream-usb
2019/10/13 01:21 https://github.com/google/kasan.git usb-fuzzer 58d5f26a5584 426631dd .config console log report ci2-upstream-usb
2019/10/13 00:12 https://github.com/google/kasan.git usb-fuzzer 58d5f26a5584 426631dd .config console log report ci2-upstream-usb
2019/10/12 23:06 https://github.com/google/kasan.git usb-fuzzer 58d5f26a5584 426631dd .config console log report ci2-upstream-usb
2019/10/12 21:38 https://github.com/google/kasan.git usb-fuzzer 58d5f26a5584 426631dd .config console log report ci2-upstream-usb
2019/10/12 19:56 https://github.com/google/kasan.git usb-fuzzer 58d5f26a5584 426631dd .config console log report ci2-upstream-usb
2019/10/12 19:13 https://github.com/google/kasan.git usb-fuzzer 58d5f26a5584 426631dd .config console log report ci2-upstream-usb
2019/10/12 17:59 https://github.com/google/kasan.git usb-fuzzer 58d5f26a5584 426631dd .config console log report ci2-upstream-usb
2019/10/12 16:09 https://github.com/google/kasan.git usb-fuzzer 58d5f26a5584 426631dd .config console log report ci2-upstream-usb
2019/10/12 14:56 https://github.com/google/kasan.git usb-fuzzer 58d5f26a5584 426631dd .config console log report ci2-upstream-usb
2019/10/12 13:45 https://github.com/google/kasan.git usb-fuzzer 58d5f26a5584 426631dd .config console log report ci2-upstream-usb
2019/10/12 12:38 https://github.com/google/kasan.git usb-fuzzer 58d5f26a5584 426631dd .config console log report ci2-upstream-usb
2019/10/12 12:09 https://github.com/google/kasan.git usb-fuzzer 58d5f26a5584 426631dd .config console log report ci2-upstream-usb
2019/08/02 21:11 https://github.com/google/kasan.git usb-fuzzer e96407b49762 3faab807 .config console log report ci2-upstream-usb
* Struck through repros no longer work on HEAD.