KASAN: use-after-free Read in dvb_usb_device_exit (2)

[syzbot]

Hello,

syzbot found the following crash on:

HEAD commit: e96407b4 usb-fuzzer: main usb gadget fuzzer driver
git tree: https://github.com/google/kasan.git usb-fuzzer
console output: https://syzkaller.appspot.com/x/log.txt?x=114fd9aa600000
kernel config: https://syzkaller.appspot.com/x/.config?x=cfa2c18fb6a8068e
dashboard link: https://syzkaller.appspot.com/bug?extid=c58e976e022432ee60b4
compiler: gcc (GCC) 9.0.0 20181231 (experimental)
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=173ee42c600000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=16d9442c600000

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+c58e97...@syzkaller.appspotmail.com

input: TeVii S421 PCI as
/devices/platform/dummy_hcd.0/usb1/1-1/rc/rc0/input5
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+0x19a/0x1a0
drivers/media/usb/dvb-usb/dvb-usb-init.c:305
Read of size 8 at addr ffff8881d50468e8 by task kworker/1:1/22

CPU: 1 PID: 22 Comm: kworker/1:1 Not tainted 5.3.0-rc2+ #25
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+0x6a/0x32c mm/kasan/report.c:351
__kasan_report.cold+0x1a/0x33 mm/kasan/report.c:482
kasan_report+0xe/0x12 mm/kasan/common.c:612
dvb_usb_device_exit+0x19a/0x1a0
drivers/media/usb/dvb-usb/dvb-usb-init.c:305
usb_unbind_interface+0x1bd/0x8a0 drivers/usb/core/driver.c:423
__device_release_driver drivers/base/dd.c:1120 [inline]
device_release_driver_internal+0x404/0x4c0 drivers/base/dd.c:1151
bus_remove_device+0x2dc/0x4a0 drivers/base/bus.c:556
device_del+0x420/0xb10 drivers/base/core.c:2288
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
process_scheduled_works kernel/workqueue.c:2331 [inline]
worker_thread+0x7ab/0xe20 kernel/workqueue.c:2417
kthread+0x318/0x420 kernel/kthread.c:255
ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352

Allocated by task 22:
save_stack+0x1b/0x80 mm/kasan/common.c:69
set_track mm/kasan/common.c:77 [inline]
__kasan_kmalloc mm/kasan/common.c:487 [inline]
__kasan_kmalloc.constprop.0+0xbf/0xd0 mm/kasan/common.c:460
slab_post_alloc_hook mm/slab.h:520 [inline]
slab_alloc_node mm/slub.c:2766 [inline]
slab_alloc mm/slub.c:2774 [inline]
__kmalloc_track_caller+0xc8/0x2a0 mm/slub.c:4331
kmemdup+0x23/0x50 mm/util.c:120
kmemdup include/linux/string.h:432 [inline]
dw2102_probe+0x627/0xc40 drivers/media/usb/dvb-usb/dw2102.c:2372
usb_probe_interface+0x305/0x7a0 drivers/usb/core/driver.c:361
really_probe+0x281/0x650 drivers/base/dd.c:548
driver_probe_device+0x101/0x1b0 drivers/base/dd.c:709
__device_attach_driver+0x1c2/0x220 drivers/base/dd.c:816
bus_for_each_drv+0x15c/0x1e0 drivers/base/bus.c:454
__device_attach+0x217/0x360 drivers/base/dd.c:882
bus_probe_device+0x1e4/0x290 drivers/base/bus.c:514
device_add+0xae6/0x16f0 drivers/base/core.c:2114
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+0x281/0x650 drivers/base/dd.c:548
driver_probe_device+0x101/0x1b0 drivers/base/dd.c:709
__device_attach_driver+0x1c2/0x220 drivers/base/dd.c:816
bus_for_each_drv+0x15c/0x1e0 drivers/base/bus.c:454
__device_attach+0x217/0x360 drivers/base/dd.c:882
bus_probe_device+0x1e4/0x290 drivers/base/bus.c:514
device_add+0xae6/0x16f0 drivers/base/core.c:2114
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 22:
save_stack+0x1b/0x80 mm/kasan/common.c:69
set_track mm/kasan/common.c:77 [inline]
__kasan_slab_free+0x130/0x180 mm/kasan/common.c:449
slab_free_hook mm/slub.c:1423 [inline]
slab_free_freelist_hook mm/slub.c:1470 [inline]
slab_free mm/slub.c:3012 [inline]
kfree+0xe4/0x2f0 mm/slub.c:3953
dw2102_probe+0x871/0xc40 drivers/media/usb/dvb-usb/dw2102.c:2406
usb_probe_interface+0x305/0x7a0 drivers/usb/core/driver.c:361
really_probe+0x281/0x650 drivers/base/dd.c:548
driver_probe_device+0x101/0x1b0 drivers/base/dd.c:709
__device_attach_driver+0x1c2/0x220 drivers/base/dd.c:816
bus_for_each_drv+0x15c/0x1e0 drivers/base/bus.c:454
__device_attach+0x217/0x360 drivers/base/dd.c:882
bus_probe_device+0x1e4/0x290 drivers/base/bus.c:514
device_add+0xae6/0x16f0 drivers/base/core.c:2114
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+0x281/0x650 drivers/base/dd.c:548
driver_probe_device+0x101/0x1b0 drivers/base/dd.c:709
__device_attach_driver+0x1c2/0x220 drivers/base/dd.c:816
bus_for_each_drv+0x15c/0x1e0 drivers/base/bus.c:454
__device_attach+0x217/0x360 drivers/base/dd.c:882
bus_probe_device+0x1e4/0x290 drivers/base/bus.c:514
device_add+0xae6/0x16f0 drivers/base/core.c:2114
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

The buggy address belongs to the object at ffff8881d5046600
which belongs to the cache kmalloc-4k of size 4096
The buggy address is located 744 bytes inside of
4096-byte region [ffff8881d5046600, ffff8881d5047600)
The buggy address belongs to the page:
page:ffffea0007541000 refcount:1 mapcount:0 mapping:ffff8881da00c280
index:0x0 compound_mapcount: 0
flags: 0x200000000010200(slab|head)
raw: 0200000000010200 dead000000000100 dead000000000122 ffff8881da00c280
raw: 0000000000000000 0000000000070007 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
ffff8881d5046780: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8881d5046800: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
> ffff8881d5046880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff8881d5046900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8881d5046980: 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.
syzbot engineers can be reached at syzk...@googlegroups.com.

syzbot will keep track of this bug report. See:
https://goo.gl/tpsmEJ#status for how to communicate with syzbot.
syzbot can test patches for this bug, for details see:
https://goo.gl/tpsmEJ#testing-patches

[Hillf Danton]

[respin due to "Sender frequency limited" and therefore the Cc list once
cut short:(]

Tue, 06 Aug 2019 06:18:08 -0700

Recompute desc after copying properties.

--- a/drivers/media/usb/dvb-usb/dvb-usb-init.c
+++ b/drivers/media/usb/dvb-usb/dvb-usb-init.c
@@ -276,7 +276,8 @@ int dvb_usb_device_init(struct usb_inter

d->udev = udev;
memcpy(&d->props, props, sizeof(struct dvb_usb_device_properties));
- d->desc = desc;
+ cold = 0;
+ d->desc = dvb_usb_find_device(udev, &d->props, &cold);
d->owner = owner;

usb_set_intfdata(intf, d);
--

[Andrey Konovalov]

#syz test: https://github.com/google/kasan.git e96407b4

[syzbot]

Hello,

syzbot has tested the proposed patch and the reproducer did not trigger
crash:

Reported-and-tested-by:
syzbot+c58e97...@syzkaller.appspotmail.com

Tested on:

commit: e96407b4 usb-fuzzer: main usb gadget fuzzer driver
git tree: https://github.com/google/kasan.git

kernel config: https://syzkaller.appspot.com/x/.config?x=cfa2c18fb6a8068e

compiler: gcc (GCC) 9.0.0 20181231 (experimental)

patch: https://syzkaller.appspot.com/x/patch.diff?x=1622161c600000

Note: testing is done by a robot and is best-effort only.

[Alexander Potapenko]

Hi Hillf,

On Thu, Aug 8, 2019 at 10:03 AM Hillf Danton <hda...@sina.com> wrote:
>
>

Did you have a chance to land this patch?
We're still seeing similar reports on the KMSAN bot.
> --
> You received this message because you are subscribed to the Google Groups "syzkaller-bugs" group.
> To unsubscribe from this group and stop receiving emails from it, send an email to syzkaller-bug...@googlegroups.com.
> To view this discussion on the web visit https://groups.google.com/d/msgid/syzkaller-bugs/20190808080330.12292-1-hdanton%40sina.com.



--
Alexander Potapenko
Software Engineer

Google Germany GmbH
Erika-Mann-Straße, 33
80636 München

Geschäftsführer: Paul Manicle, Halimah DeLaine Prado
Registergericht und -nummer: Hamburg, HRB 86891
Sitz der Gesellschaft: Hamburg

[Hillf Danton]

On Mon, 25 Nov 2019 14:40:07 +0100 Alexander Potapenko wrote:
> Hi Hillf,

>
> Did you have a chance to land this patch?
> We're still seeing similar reports on the KMSAN bot.

Hey Alexander,

Feel free to pick it up please if it makes a sense to you.

I would have done that but my mail agent failed to deliver
whatever I edited to x...@vger.kernel.org (try search my posts
at lore.kernel.org).

Hillf

[syzbot]

Auto-closing this bug as obsolete.
No recent activity, existing reproducers are no longer triggering the issue.