Hello,
syzbot found the following crash on:
HEAD commit: 9a33b369 usb-fuzzer: main usb gadget fuzzer driver
git tree: https://github.com/google/kasan/tree/usb-fuzzer
console output: https://syzkaller.appspot.com/x/log.txt?x=1643974b200000
kernel config: https://syzkaller.appspot.com/x/.config?x=23e37f59d94ddd15
dashboard link: https://syzkaller.appspot.com/bug?extid=26ec41e9f788b3eba396
compiler: gcc (GCC) 9.0.0 20181231 (experimental)
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=12f5efa7200000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=1395a0f3200000
IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+26ec41e9f788b3eba396@xxxxxxxxxxxxxxxxxxxxxxxxx
dvb-usb: schedule remote query interval to 150 msecs.
dw2102: su3000_power_ctrl: 0, initialized 1
dvb-usb: TeVii S421 PCI successfully initialized and connected.
usb 1-1: USB disconnect, device number 2
==================================================================
BUG: KASAN: use-after-free in dvb_usb_device_exit+0xbb/0xd0
drivers/media/usb/dvb-usb/dvb-usb-init.c:294
Read of size 8 at addr ffff88809ec693d8 by task kworker/1:1/21
CPU: 1 PID: 21 Comm: kworker/1:1 Not tainted 5.1.0-rc4-319354-g9a33b36 #3
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+0xe8/0x16e lib/dump_stack.c:113
print_address_description+0x6c/0x236 mm/kasan/report.c:187
kasan_report.cold+0x1a/0x3c mm/kasan/report.c:317
dvb_usb_device_exit+0xbb/0xd0 drivers/media/usb/dvb-usb/dvb-usb-init.c:294
usb_unbind_interface+0x1c9/0x980 drivers/usb/core/driver.c:423
__device_release_driver drivers/base/dd.c:1082 [inline]
device_release_driver_internal+0x436/0x4f0 drivers/base/dd.c:1113
bus_remove_device+0x302/0x5c0 drivers/base/bus.c:556
device_del+0x467/0xb90 drivers/base/core.c:2269
usb_disable_device+0x242/0x790 drivers/usb/core/message.c:1235
usb_disconnect+0x298/0x870 drivers/usb/core/hub.c:2197
hub_port_connect drivers/usb/core/hub.c:4940 [inline]
hub_port_connect_change drivers/usb/core/hub.c:5204 [inline]
port_event drivers/usb/core/hub.c:5350 [inline]
hub_event+0xcd2/0x3b00 drivers/usb/core/hub.c:5432
process_one_work+0x90f/0x1580 kernel/workqueue.c:2269
process_scheduled_works kernel/workqueue.c:2331 [inline]
worker_thread+0x7b0/0xe20 kernel/workqueue.c:2417
kthread+0x313/0x420 kernel/kthread.c:253
ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:352
Allocated by task 21:
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
slab_post_alloc_hook mm/slab.h:437 [inline]
slab_alloc_node mm/slub.c:2756 [inline]
slab_alloc mm/slub.c:2764 [inline]
__kmalloc_track_caller+0xf0/0x2c0 mm/slub.c:4342
kmemdup+0x23/0x50 mm/util.c:118
kmemdup include/linux/string.h:428 [inline]
dw2102_probe+0x62c/0xc50 drivers/media/usb/dvb-usb/dw2102.c:2375
usb_probe_interface+0x31d/0x820 drivers/usb/core/driver.c:361
really_probe+0x2da/0xb10 drivers/base/dd.c:509
driver_probe_device+0x21d/0x350 drivers/base/dd.c:671
__device_attach_driver+0x1d8/0x290 drivers/base/dd.c:778
bus_for_each_drv+0x163/0x1e0 drivers/base/bus.c:454
__device_attach+0x223/0x3a0 drivers/base/dd.c:844
bus_probe_device+0x1f1/0x2a0 drivers/base/bus.c:514
device_add+0xad2/0x16e0 drivers/base/core.c:2106
usb_set_configuration+0xdf7/0x1740 drivers/usb/core/message.c:2021
generic_probe+0xa2/0xda drivers/usb/core/generic.c:210
usb_probe_device+0xc0/0x150 drivers/usb/core/driver.c:266
really_probe+0x2da/0xb10 drivers/base/dd.c:509
driver_probe_device+0x21d/0x350 drivers/base/dd.c:671
__device_attach_driver+0x1d8/0x290 drivers/base/dd.c:778
bus_for_each_drv+0x163/0x1e0 drivers/base/bus.c:454
__device_attach+0x223/0x3a0 drivers/base/dd.c:844
bus_probe_device+0x1f1/0x2a0 drivers/base/bus.c:514
device_add+0xad2/0x16e0 drivers/base/core.c:2106
usb_new_device.cold+0x537/0xccf 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+0x138e/0x3b00 drivers/usb/core/hub.c:5432
process_one_work+0x90f/0x1580 kernel/workqueue.c:2269
worker_thread+0x9b/0xe20 kernel/workqueue.c:2415
kthread+0x313/0x420 kernel/kthread.c:253
ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:352
Freed by task 21:
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+0x5e/0x140 mm/slub.c:1456
slab_free mm/slub.c:3003 [inline]
kfree+0xce/0x290 mm/slub.c:3958
dw2102_probe+0x876/0xc50 drivers/media/usb/dvb-usb/dw2102.c:2409
usb_probe_interface+0x31d/0x820 drivers/usb/core/driver.c:361
really_probe+0x2da/0xb10 drivers/base/dd.c:509
driver_probe_device+0x21d/0x350 drivers/base/dd.c:671
__device_attach_driver+0x1d8/0x290 drivers/base/dd.c:778
bus_for_each_drv+0x163/0x1e0 drivers/base/bus.c:454
__device_attach+0x223/0x3a0 drivers/base/dd.c:844
bus_probe_device+0x1f1/0x2a0 drivers/base/bus.c:514
device_add+0xad2/0x16e0 drivers/base/core.c:2106
usb_set_configuration+0xdf7/0x1740 drivers/usb/core/message.c:2021
generic_probe+0xa2/0xda drivers/usb/core/generic.c:210
usb_probe_device+0xc0/0x150 drivers/usb/core/driver.c:266
really_probe+0x2da/0xb10 drivers/base/dd.c:509
driver_probe_device+0x21d/0x350 drivers/base/dd.c:671
__device_attach_driver+0x1d8/0x290 drivers/base/dd.c:778
bus_for_each_drv+0x163/0x1e0 drivers/base/bus.c:454
__device_attach+0x223/0x3a0 drivers/base/dd.c:844
bus_probe_device+0x1f1/0x2a0 drivers/base/bus.c:514
device_add+0xad2/0x16e0 drivers/base/core.c:2106
usb_new_device.cold+0x537/0xccf 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+0x138e/0x3b00 drivers/usb/core/hub.c:5432
process_one_work+0x90f/0x1580 kernel/workqueue.c:2269
worker_thread+0x9b/0xe20 kernel/workqueue.c:2415
kthread+0x313/0x420 kernel/kthread.c:253
ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:352
The buggy address belongs to the object at ffff88809ec69100
which belongs to the cache kmalloc-4k of size 4096
The buggy address is located 728 bytes inside of
4096-byte region [ffff88809ec69100, ffff88809ec6a100)
The buggy address belongs to the page:
page:ffffea00027b1a00 count:1 mapcount:0 mapping:ffff88812c3f4600 index:0x0
compound_mapcount: 0
flags: 0xfff00000010200(slab|head)
raw: 00fff00000010200 dead000000000100 dead000000000200 ffff88812c3f4600
raw: 0000000000000000 0000000000070007 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected
Memory state around the buggy address:
ffff88809ec69280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff88809ec69300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff88809ec69380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff88809ec69400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff88809ec69480: 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.
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