syzbot


KASAN: use-after-free Read in build_audio_procunit

Status: closed as dup on 2019/10/24 13:49
Subsystems: sound usb
[Documentation on labels]
Reported-by: syzbot+fd965c77e4711eb13b82@syzkaller.appspotmail.com
First crash: 1595d, last: 1592d
Duplicate of
Title Repro Cause bisect Fix bisect Count Last Reported
KASAN: slab-out-of-bounds Read in build_audio_procunit usb sound C 6 1587d 1596d
Discussions (1)
Title Replies (including bot) Last reply
KASAN: use-after-free Read in build_audio_procunit 1 (2) 2019/10/24 13:49

Sample crash report:
usb 1-1: New USB device strings: Mfr=1, Product=2, SerialNumber=3
usb 1-1: Product: syz
usb 1-1: Manufacturer: syz
usb 1-1: SerialNumber: syz
==================================================================
BUG: KASAN: use-after-free in uac_extension_unit_iExtension include/uapi/linux/usb/audio.h:483 [inline]
BUG: KASAN: use-after-free in build_audio_procunit+0xeab/0x13f0 sound/usb/mixer.c:2434
Read of size 1 at addr ffff8881d545362b by task kworker/1:2/83

CPU: 1 PID: 83 Comm: kworker/1:2 Not tainted 5.4.0-rc3+ #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/0x20 mm/kasan/common.c:634
 uac_extension_unit_iExtension include/uapi/linux/usb/audio.h:483 [inline]
 build_audio_procunit+0xeab/0x13f0 sound/usb/mixer.c:2434
 parse_audio_extension_unit sound/usb/mixer.c:2483 [inline]
 parse_audio_unit+0x1812/0x36f0 sound/usb/mixer.c:2761
 snd_usb_mixer_controls+0x715/0xb90 sound/usb/mixer.c:3095
 snd_usb_create_mixer+0x2b5/0x1890 sound/usb/mixer.c:3445
 usb_audio_probe+0xc76/0x2010 sound/usb/card.c:653
 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:5183 [inline]
 hub_port_connect_change drivers/usb/core/hub.c:5323 [inline]
 port_event drivers/usb/core/hub.c:5469 [inline]
 hub_event+0x1dd0/0x37e0 drivers/usb/core/hub.c:5551
 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 83:
 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:561 [inline]
 usb_alloc_urb+0x65/0xb0 drivers/usb/core/urb.c:73
 usb_internal_control_msg drivers/usb/core/message.c:94 [inline]
 usb_control_msg+0x1c9/0x4a0 drivers/usb/core/message.c:152
 usb_get_descriptor+0xc1/0x1b0 drivers/usb/core/message.c:647
 usb_get_configuration+0x28e/0x3050 drivers/usb/core/config.c:836
 usb_enumerate_device drivers/usb/core/hub.c:2369 [inline]
 usb_new_device+0xd3/0x160 drivers/usb/core/hub.c:2505
 hub_port_connect drivers/usb/core/hub.c:5183 [inline]
 hub_port_connect_change drivers/usb/core/hub.c:5323 [inline]
 port_event drivers/usb/core/hub.c:5469 [inline]
 hub_event+0x1dd0/0x37e0 drivers/usb/core/hub.c:5551
 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 83:
 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+0xe4/0x320 mm/slub.c:3967
 urb_destroy drivers/usb/core/urb.c:26 [inline]
 kref_put include/linux/kref.h:65 [inline]
 usb_free_urb.part.0+0x7a/0xc0 drivers/usb/core/urb.c:95
 usb_free_urb+0x1b/0x30 drivers/usb/core/urb.c:94
 usb_start_wait_urb+0x1e5/0x2b0 drivers/usb/core/message.c:79
 usb_internal_control_msg drivers/usb/core/message.c:101 [inline]
 usb_control_msg+0x31c/0x4a0 drivers/usb/core/message.c:152
 usb_get_descriptor+0xc1/0x1b0 drivers/usb/core/message.c:647
 usb_get_configuration+0x28e/0x3050 drivers/usb/core/config.c:836
 usb_enumerate_device drivers/usb/core/hub.c:2369 [inline]
 usb_new_device+0xd3/0x160 drivers/usb/core/hub.c:2505
 hub_port_connect drivers/usb/core/hub.c:5183 [inline]
 hub_port_connect_change drivers/usb/core/hub.c:5323 [inline]
 port_event drivers/usb/core/hub.c:5469 [inline]
 hub_event+0x1dd0/0x37e0 drivers/usb/core/hub.c:5551
 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

The buggy address belongs to the object at ffff8881d5453600
 which belongs to the cache kmalloc-192 of size 192
The buggy address is located 43 bytes inside of
 192-byte region [ffff8881d5453600, ffff8881d54536c0)
The buggy address belongs to the page:
page:ffffea00075514c0 refcount:1 mapcount:0 mapping:ffff8881da002a00 index:0x0
flags: 0x200000000000200(slab)
raw: 0200000000000200 ffffea00075512c0 0000000b0000000b ffff8881da002a00
raw: 0000000000000000 0000000000100010 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8881d5453500: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff8881d5453580: 00 00 00 07 fc fc fc fc fc fc fc fc fc fc fc fc
>ffff8881d5453600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                  ^
 ffff8881d5453680: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
 ffff8881d5453700: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2019/10/25 20:41 https://github.com/google/kasan.git usb-fuzzer 22be26f76193 04ca72cd .config console log report syz C ci2-upstream-usb
2019/10/23 03:41 https://github.com/google/kasan.git usb-fuzzer 22be26f76193 d0686497 .config console log report syz C ci2-upstream-usb
* Struck through repros no longer work on HEAD.