* usb/media/dtt200u: use-after-free in __dvb_frontend_free
@ 2017-10-23 14:41 Andrey Konovalov
2017-10-23 18:58 ` Matthias Schwarzott
0 siblings, 1 reply; 5+ messages in thread
From: Andrey Konovalov @ 2017-10-23 14:41 UTC (permalink / raw)
To: Mauro Carvalho Chehab, Max Kellermann, linux-media, LKML
Cc: Dmitry Vyukov, Kostya Serebryany, syzkaller
Hi!
I've got the following report while fuzzing the kernel with syzkaller.
On commit 3e0cc09a3a2c40ec1ffb6b4e12da86e98feccb11 (4.14-rc5+).
dvb-usb: found a 'WideView WT-220U PenType Receiver (based on ZL353)'
in warm state.
dvb-usb: bulk message failed: -22 (2/1102416563)
dvb-usb: will use the device's hardware PID filter (table count: 15).
dvbdev: DVB: registering new adapter (WideView WT-220U PenType
Receiver (based on ZL353))
usb 1-1: media controller created
dvbdev: dvb_create_media_entity: media entity 'dvb-demux' registered.
usb 1-1: DVB: registering adapter 0 frontend 0 (WideView USB DVB-T)...
dvbdev: dvb_create_media_entity: media entity 'WideView USB DVB-T' registered.
Registered IR keymap rc-dtt200u
rc rc1: IR-receiver inside an USB DVB receiver as
/devices/platform/dummy_hcd.0/usb1/1-1/rc/rc1
input: IR-receiver inside an USB DVB receiver as
/devices/platform/dummy_hcd.0/usb1/1-1/rc/rc1/input9
dvb-usb: schedule remote query interval to 300 msecs.
dvb-usb: WideView WT-220U PenType Receiver (based on ZL353)
successfully initialized and connected.
dvb-usb: bulk message failed: -22 (1/1807119384)
dvb-usb: error -22 while querying for an remote control event.
dvb-usb: bulk message failed: -22 (1/1807119384)
dvb-usb: error -22 while querying for an remote control event.
dvb-usb: bulk message failed: -22 (1/1807119384)
dvb-usb: error -22 while querying for an remote control event.
dvb-usb: bulk message failed: -22 (1/1807119384)
dvb-usb: error -22 while querying for an remote control event.
dvb-usb: bulk message failed: -22 (1/1807119384)
dvb-usb: error -22 while querying for an remote control event.
dvb-usb: bulk message failed: -22 (1/1807119384)
dvb-usb: error -22 while querying for an remote control event.
usb 1-1: USB disconnect, device number 2
==================================================================
BUG: KASAN: use-after-free in __dvb_frontend_free+0x113/0x120
Write of size 8 at addr ffff880067d45a00 by task kworker/0:1/24
CPU: 0 PID: 24 Comm: kworker/0:1 Not tainted 4.14.0-rc5-43687-g06ab8a23e0e6 #545
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011
Workqueue: usb_hub_wq hub_event
Call Trace:
__dump_stack lib/dump_stack.c:16
dump_stack+0x292/0x395 lib/dump_stack.c:52
print_address_description+0x78/0x280 mm/kasan/report.c:252
kasan_report_error mm/kasan/report.c:351
kasan_report+0x23d/0x350 mm/kasan/report.c:409
__asan_report_store8_noabort+0x1c/0x20 mm/kasan/report.c:435
__dvb_frontend_free+0x113/0x120 drivers/media/dvb-core/dvb_frontend.c:156
dvb_frontend_put+0x59/0x70 drivers/media/dvb-core/dvb_frontend.c:176
dvb_frontend_detach+0x120/0x150 drivers/media/dvb-core/dvb_frontend.c:2803
dvb_usb_adapter_frontend_exit+0xd6/0x160
drivers/media/usb/dvb-usb/dvb-usb-dvb.c:340
dvb_usb_adapter_exit drivers/media/usb/dvb-usb/dvb-usb-init.c:116
dvb_usb_exit+0x9b/0x200 drivers/media/usb/dvb-usb/dvb-usb-init.c:132
dvb_usb_device_exit+0xa5/0xf0 drivers/media/usb/dvb-usb/dvb-usb-init.c:295
usb_unbind_interface+0x21c/0xa90 drivers/usb/core/driver.c:423
__device_release_driver drivers/base/dd.c:861
device_release_driver_internal+0x4f1/0x5c0 drivers/base/dd.c:893
device_release_driver+0x1e/0x30 drivers/base/dd.c:918
bus_remove_device+0x2f4/0x4b0 drivers/base/bus.c:565
device_del+0x5c4/0xab0 drivers/base/core.c:1985
usb_disable_device+0x1e9/0x680 drivers/usb/core/message.c:1170
usb_disconnect+0x260/0x7a0 drivers/usb/core/hub.c:2124
hub_port_connect drivers/usb/core/hub.c:4754
hub_port_connect_change drivers/usb/core/hub.c:5009
port_event drivers/usb/core/hub.c:5115
hub_event+0x1318/0x3740 drivers/usb/core/hub.c:5195
process_one_work+0xc73/0x1d90 kernel/workqueue.c:2119
worker_thread+0x221/0x1850 kernel/workqueue.c:2253
kthread+0x363/0x440 kernel/kthread.c:231
ret_from_fork+0x2a/0x40 arch/x86/entry/entry_64.S:431
Allocated by task 24:
save_stack_trace+0x1b/0x20 arch/x86/kernel/stacktrace.c:59
save_stack+0x43/0xd0 mm/kasan/kasan.c:447
set_track mm/kasan/kasan.c:459
kasan_kmalloc+0xad/0xe0 mm/kasan/kasan.c:551
kmem_cache_alloc_trace+0x11e/0x2d0 mm/slub.c:2772
kmalloc ./include/linux/slab.h:493
kzalloc ./include/linux/slab.h:666
dtt200u_fe_attach+0x4c/0x110 drivers/media/usb/dvb-usb/dtt200u-fe.c:212
dtt200u_frontend_attach+0x35/0x80 drivers/media/usb/dvb-usb/dtt200u.c:136
dvb_usb_adapter_frontend_init+0x32b/0x660
drivers/media/usb/dvb-usb/dvb-usb-dvb.c:286
dvb_usb_adapter_init drivers/media/usb/dvb-usb/dvb-usb-init.c:86
dvb_usb_init drivers/media/usb/dvb-usb/dvb-usb-init.c:162
dvb_usb_device_init+0xf73/0x17f0 drivers/media/usb/dvb-usb/dvb-usb-init.c:277
dtt200u_usb_probe+0xa1/0xe0 drivers/media/usb/dvb-usb/dtt200u.c:155
usb_probe_interface+0x35d/0x8e0 drivers/usb/core/driver.c:361
really_probe drivers/base/dd.c:413
driver_probe_device+0x610/0xa00 drivers/base/dd.c:557
__device_attach_driver+0x230/0x290 drivers/base/dd.c:653
bus_for_each_drv+0x161/0x210 drivers/base/bus.c:463
__device_attach+0x26b/0x3c0 drivers/base/dd.c:710
device_initial_probe+0x1f/0x30 drivers/base/dd.c:757
bus_probe_device+0x1eb/0x290 drivers/base/bus.c:523
device_add+0xd0b/0x1660 drivers/base/core.c:1835
usb_set_configuration+0x104e/0x1870 drivers/usb/core/message.c:1932
generic_probe+0x73/0xe0 drivers/usb/core/generic.c:174
usb_probe_device+0xaf/0xe0 drivers/usb/core/driver.c:266
really_probe drivers/base/dd.c:413
driver_probe_device+0x610/0xa00 drivers/base/dd.c:557
__device_attach_driver+0x230/0x290 drivers/base/dd.c:653
bus_for_each_drv+0x161/0x210 drivers/base/bus.c:463
__device_attach+0x26b/0x3c0 drivers/base/dd.c:710
device_initial_probe+0x1f/0x30 drivers/base/dd.c:757
bus_probe_device+0x1eb/0x290 drivers/base/bus.c:523
device_add+0xd0b/0x1660 drivers/base/core.c:1835
usb_new_device+0x7b8/0x1020 drivers/usb/core/hub.c:2457
hub_port_connect drivers/usb/core/hub.c:4903
hub_port_connect_change drivers/usb/core/hub.c:5009
port_event drivers/usb/core/hub.c:5115
hub_event+0x194d/0x3740 drivers/usb/core/hub.c:5195
process_one_work+0xc73/0x1d90 kernel/workqueue.c:2119
worker_thread+0x221/0x1850 kernel/workqueue.c:2253
kthread+0x363/0x440 kernel/kthread.c:231
ret_from_fork+0x2a/0x40 arch/x86/entry/entry_64.S:431
Freed by task 24:
save_stack_trace+0x1b/0x20 arch/x86/kernel/stacktrace.c:59
save_stack+0x43/0xd0 mm/kasan/kasan.c:447
set_track mm/kasan/kasan.c:459
kasan_slab_free+0x72/0xc0 mm/kasan/kasan.c:524
slab_free_hook mm/slub.c:1390
slab_free_freelist_hook mm/slub.c:1412
slab_free mm/slub.c:2988
kfree+0xf6/0x2f0 mm/slub.c:3919
dtt200u_fe_release+0x3c/0x50 drivers/media/usb/dvb-usb/dtt200u-fe.c:202
dvb_frontend_invoke_release.part.13+0x1c/0x30
drivers/media/dvb-core/dvb_frontend.c:2790
dvb_frontend_invoke_release drivers/media/dvb-core/dvb_frontend.c:2789
__dvb_frontend_free+0xad/0x120 drivers/media/dvb-core/dvb_frontend.c:153
dvb_frontend_put+0x59/0x70 drivers/media/dvb-core/dvb_frontend.c:176
dvb_frontend_detach+0x120/0x150 drivers/media/dvb-core/dvb_frontend.c:2803
dvb_usb_adapter_frontend_exit+0xd6/0x160
drivers/media/usb/dvb-usb/dvb-usb-dvb.c:340
dvb_usb_adapter_exit drivers/media/usb/dvb-usb/dvb-usb-init.c:116
dvb_usb_exit+0x9b/0x200 drivers/media/usb/dvb-usb/dvb-usb-init.c:132
dvb_usb_device_exit+0xa5/0xf0 drivers/media/usb/dvb-usb/dvb-usb-init.c:295
usb_unbind_interface+0x21c/0xa90 drivers/usb/core/driver.c:423
__device_release_driver drivers/base/dd.c:861
device_release_driver_internal+0x4f1/0x5c0 drivers/base/dd.c:893
device_release_driver+0x1e/0x30 drivers/base/dd.c:918
bus_remove_device+0x2f4/0x4b0 drivers/base/bus.c:565
device_del+0x5c4/0xab0 drivers/base/core.c:1985
usb_disable_device+0x1e9/0x680 drivers/usb/core/message.c:1170
usb_disconnect+0x260/0x7a0 drivers/usb/core/hub.c:2124
hub_port_connect drivers/usb/core/hub.c:4754
hub_port_connect_change drivers/usb/core/hub.c:5009
port_event drivers/usb/core/hub.c:5115
hub_event+0x1318/0x3740 drivers/usb/core/hub.c:5195
process_one_work+0xc73/0x1d90 kernel/workqueue.c:2119
worker_thread+0x221/0x1850 kernel/workqueue.c:2253
kthread+0x363/0x440 kernel/kthread.c:231
ret_from_fork+0x2a/0x40 arch/x86/entry/entry_64.S:431
The buggy address belongs to the object at ffff880067d45500
which belongs to the cache kmalloc-2048 of size 2048
The buggy address is located 1280 bytes inside of
2048-byte region [ffff880067d45500, ffff880067d45d00)
The buggy address belongs to the page:
page:ffffea00019f5000 count:1 mapcount:0 mapping: (null)
index:0x0 compound_mapcount: 0
flags: 0x100000000008100(slab|head)
raw: 0100000000008100 0000000000000000 0000000000000000 00000001000f000f
raw: dead000000000100 dead000000000200 ffff88006c002d80 0000000000000000
page dumped because: kasan: bad access detected
Memory state around the buggy address:
ffff880067d45900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff880067d45980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff880067d45a00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff880067d45a80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff880067d45b00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
^ permalink raw reply [flat|nested] 5+ messages in thread* Re: usb/media/dtt200u: use-after-free in __dvb_frontend_free 2017-10-23 14:41 usb/media/dtt200u: use-after-free in __dvb_frontend_free Andrey Konovalov @ 2017-10-23 18:58 ` Matthias Schwarzott 2017-10-24 11:19 ` Andrey Konovalov 2017-11-07 10:31 ` Mauro Carvalho Chehab 0 siblings, 2 replies; 5+ messages in thread From: Matthias Schwarzott @ 2017-10-23 18:58 UTC (permalink / raw) To: Andrey Konovalov, Mauro Carvalho Chehab, Max Kellermann, linux-media, LKML Cc: Dmitry Vyukov, Kostya Serebryany, syzkaller Am 23.10.2017 um 16:41 schrieb Andrey Konovalov: > Hi! > > I've got the following report while fuzzing the kernel with syzkaller. > > On commit 3e0cc09a3a2c40ec1ffb6b4e12da86e98feccb11 (4.14-rc5+). > > dvb-usb: found a 'WideView WT-220U PenType Receiver (based on ZL353)' > in warm state. > dvb-usb: bulk message failed: -22 (2/1102416563) > dvb-usb: will use the device's hardware PID filter (table count: 15). > dvbdev: DVB: registering new adapter (WideView WT-220U PenType > Receiver (based on ZL353)) > usb 1-1: media controller created > dvbdev: dvb_create_media_entity: media entity 'dvb-demux' registered. > usb 1-1: DVB: registering adapter 0 frontend 0 (WideView USB DVB-T)... > dvbdev: dvb_create_media_entity: media entity 'WideView USB DVB-T' registered. > Registered IR keymap rc-dtt200u > rc rc1: IR-receiver inside an USB DVB receiver as > /devices/platform/dummy_hcd.0/usb1/1-1/rc/rc1 > input: IR-receiver inside an USB DVB receiver as > /devices/platform/dummy_hcd.0/usb1/1-1/rc/rc1/input9 > dvb-usb: schedule remote query interval to 300 msecs. > dvb-usb: WideView WT-220U PenType Receiver (based on ZL353) > successfully initialized and connected. > dvb-usb: bulk message failed: -22 (1/1807119384) > dvb-usb: error -22 while querying for an remote control event. > dvb-usb: bulk message failed: -22 (1/1807119384) > dvb-usb: error -22 while querying for an remote control event. > dvb-usb: bulk message failed: -22 (1/1807119384) > dvb-usb: error -22 while querying for an remote control event. > dvb-usb: bulk message failed: -22 (1/1807119384) > dvb-usb: error -22 while querying for an remote control event. > dvb-usb: bulk message failed: -22 (1/1807119384) > dvb-usb: error -22 while querying for an remote control event. > dvb-usb: bulk message failed: -22 (1/1807119384) > dvb-usb: error -22 while querying for an remote control event. > usb 1-1: USB disconnect, device number 2 > ================================================================== > BUG: KASAN: use-after-free in __dvb_frontend_free+0x113/0x120 > Write of size 8 at addr ffff880067d45a00 by task kworker/0:1/24 > > CPU: 0 PID: 24 Comm: kworker/0:1 Not tainted 4.14.0-rc5-43687-g06ab8a23e0e6 #545 > Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011 > Workqueue: usb_hub_wq hub_event > Call Trace: > __dump_stack lib/dump_stack.c:16 > dump_stack+0x292/0x395 lib/dump_stack.c:52 > print_address_description+0x78/0x280 mm/kasan/report.c:252 > kasan_report_error mm/kasan/report.c:351 > kasan_report+0x23d/0x350 mm/kasan/report.c:409 > __asan_report_store8_noabort+0x1c/0x20 mm/kasan/report.c:435 > __dvb_frontend_free+0x113/0x120 drivers/media/dvb-core/dvb_frontend.c:156 > dvb_frontend_put+0x59/0x70 drivers/media/dvb-core/dvb_frontend.c:176 > dvb_frontend_detach+0x120/0x150 drivers/media/dvb-core/dvb_frontend.c:2803 > dvb_usb_adapter_frontend_exit+0xd6/0x160 > drivers/media/usb/dvb-usb/dvb-usb-dvb.c:340 > dvb_usb_adapter_exit drivers/media/usb/dvb-usb/dvb-usb-init.c:116 > dvb_usb_exit+0x9b/0x200 drivers/media/usb/dvb-usb/dvb-usb-init.c:132 > dvb_usb_device_exit+0xa5/0xf0 drivers/media/usb/dvb-usb/dvb-usb-init.c:295 > usb_unbind_interface+0x21c/0xa90 drivers/usb/core/driver.c:423 > __device_release_driver drivers/base/dd.c:861 > device_release_driver_internal+0x4f1/0x5c0 drivers/base/dd.c:893 > device_release_driver+0x1e/0x30 drivers/base/dd.c:918 > bus_remove_device+0x2f4/0x4b0 drivers/base/bus.c:565 > device_del+0x5c4/0xab0 drivers/base/core.c:1985 > usb_disable_device+0x1e9/0x680 drivers/usb/core/message.c:1170 > usb_disconnect+0x260/0x7a0 drivers/usb/core/hub.c:2124 > hub_port_connect drivers/usb/core/hub.c:4754 > hub_port_connect_change drivers/usb/core/hub.c:5009 > port_event drivers/usb/core/hub.c:5115 > hub_event+0x1318/0x3740 drivers/usb/core/hub.c:5195 > process_one_work+0xc73/0x1d90 kernel/workqueue.c:2119 > worker_thread+0x221/0x1850 kernel/workqueue.c:2253 > kthread+0x363/0x440 kernel/kthread.c:231 > ret_from_fork+0x2a/0x40 arch/x86/entry/entry_64.S:431 > It looks like this is caused by commit ead666000a5fe34bdc82d61838e4df2d416ea15e ("media: dvb_frontend: only use kref after initialized"). The writing to "fe->frontend_priv" in dvb_frontend.c:156 is a use-after-free in case the object dvb_frontend *fe is already freed by the release callback called in line 153. Only if the demod driver is based on new style i2c_client the memory is still accessible. There are two possible solutions: 1. Clear fe->frontend_priv earlier (before line 153). 2. Do not clear fe->frontend_priv Can you try if the following patch (solution 1) fixes the issue? Regards Matthias diff --git a/drivers/media/dvb-core/dvb_frontend.c b/drivers/media/dvb-core/dvb_frontend.c index daaf969719e4..f552acdb7d8c 100644 --- a/drivers/media/dvb-core/dvb_frontend.c +++ b/drivers/media/dvb-core/dvb_frontend.c @@ -150,10 +150,11 @@ static void __dvb_frontend_free(struct dvb_frontend *fe) dvb_free_device(fepriv->dvbdev); + fe->frontend_priv = NULL; + dvb_frontend_invoke_release(fe, fe->ops.release); kfree(fepriv); - fe->frontend_priv = NULL; } static void dvb_frontend_free(struct kref *ref) ^ permalink raw reply related [flat|nested] 5+ messages in thread
* Re: usb/media/dtt200u: use-after-free in __dvb_frontend_free 2017-10-23 18:58 ` Matthias Schwarzott @ 2017-10-24 11:19 ` Andrey Konovalov 2017-11-07 10:31 ` Mauro Carvalho Chehab 1 sibling, 0 replies; 5+ messages in thread From: Andrey Konovalov @ 2017-10-24 11:19 UTC (permalink / raw) To: Matthias Schwarzott Cc: Mauro Carvalho Chehab, Max Kellermann, linux-media, LKML, Dmitry Vyukov, Kostya Serebryany, syzkaller On Mon, Oct 23, 2017 at 8:58 PM, Matthias Schwarzott <zzam@gentoo.org> wrote: > Am 23.10.2017 um 16:41 schrieb Andrey Konovalov: >> Hi! >> >> I've got the following report while fuzzing the kernel with syzkaller. >> >> On commit 3e0cc09a3a2c40ec1ffb6b4e12da86e98feccb11 (4.14-rc5+). >> >> dvb-usb: found a 'WideView WT-220U PenType Receiver (based on ZL353)' >> in warm state. >> dvb-usb: bulk message failed: -22 (2/1102416563) >> dvb-usb: will use the device's hardware PID filter (table count: 15). >> dvbdev: DVB: registering new adapter (WideView WT-220U PenType >> Receiver (based on ZL353)) >> usb 1-1: media controller created >> dvbdev: dvb_create_media_entity: media entity 'dvb-demux' registered. >> usb 1-1: DVB: registering adapter 0 frontend 0 (WideView USB DVB-T)... >> dvbdev: dvb_create_media_entity: media entity 'WideView USB DVB-T' registered. >> Registered IR keymap rc-dtt200u >> rc rc1: IR-receiver inside an USB DVB receiver as >> /devices/platform/dummy_hcd.0/usb1/1-1/rc/rc1 >> input: IR-receiver inside an USB DVB receiver as >> /devices/platform/dummy_hcd.0/usb1/1-1/rc/rc1/input9 >> dvb-usb: schedule remote query interval to 300 msecs. >> dvb-usb: WideView WT-220U PenType Receiver (based on ZL353) >> successfully initialized and connected. >> dvb-usb: bulk message failed: -22 (1/1807119384) >> dvb-usb: error -22 while querying for an remote control event. >> dvb-usb: bulk message failed: -22 (1/1807119384) >> dvb-usb: error -22 while querying for an remote control event. >> dvb-usb: bulk message failed: -22 (1/1807119384) >> dvb-usb: error -22 while querying for an remote control event. >> dvb-usb: bulk message failed: -22 (1/1807119384) >> dvb-usb: error -22 while querying for an remote control event. >> dvb-usb: bulk message failed: -22 (1/1807119384) >> dvb-usb: error -22 while querying for an remote control event. >> dvb-usb: bulk message failed: -22 (1/1807119384) >> dvb-usb: error -22 while querying for an remote control event. >> usb 1-1: USB disconnect, device number 2 >> ================================================================== >> BUG: KASAN: use-after-free in __dvb_frontend_free+0x113/0x120 >> Write of size 8 at addr ffff880067d45a00 by task kworker/0:1/24 >> >> CPU: 0 PID: 24 Comm: kworker/0:1 Not tainted 4.14.0-rc5-43687-g06ab8a23e0e6 #545 >> Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011 >> Workqueue: usb_hub_wq hub_event >> Call Trace: >> __dump_stack lib/dump_stack.c:16 >> dump_stack+0x292/0x395 lib/dump_stack.c:52 >> print_address_description+0x78/0x280 mm/kasan/report.c:252 >> kasan_report_error mm/kasan/report.c:351 >> kasan_report+0x23d/0x350 mm/kasan/report.c:409 >> __asan_report_store8_noabort+0x1c/0x20 mm/kasan/report.c:435 >> __dvb_frontend_free+0x113/0x120 drivers/media/dvb-core/dvb_frontend.c:156 >> dvb_frontend_put+0x59/0x70 drivers/media/dvb-core/dvb_frontend.c:176 >> dvb_frontend_detach+0x120/0x150 drivers/media/dvb-core/dvb_frontend.c:2803 >> dvb_usb_adapter_frontend_exit+0xd6/0x160 >> drivers/media/usb/dvb-usb/dvb-usb-dvb.c:340 >> dvb_usb_adapter_exit drivers/media/usb/dvb-usb/dvb-usb-init.c:116 >> dvb_usb_exit+0x9b/0x200 drivers/media/usb/dvb-usb/dvb-usb-init.c:132 >> dvb_usb_device_exit+0xa5/0xf0 drivers/media/usb/dvb-usb/dvb-usb-init.c:295 >> usb_unbind_interface+0x21c/0xa90 drivers/usb/core/driver.c:423 >> __device_release_driver drivers/base/dd.c:861 >> device_release_driver_internal+0x4f1/0x5c0 drivers/base/dd.c:893 >> device_release_driver+0x1e/0x30 drivers/base/dd.c:918 >> bus_remove_device+0x2f4/0x4b0 drivers/base/bus.c:565 >> device_del+0x5c4/0xab0 drivers/base/core.c:1985 >> usb_disable_device+0x1e9/0x680 drivers/usb/core/message.c:1170 >> usb_disconnect+0x260/0x7a0 drivers/usb/core/hub.c:2124 >> hub_port_connect drivers/usb/core/hub.c:4754 >> hub_port_connect_change drivers/usb/core/hub.c:5009 >> port_event drivers/usb/core/hub.c:5115 >> hub_event+0x1318/0x3740 drivers/usb/core/hub.c:5195 >> process_one_work+0xc73/0x1d90 kernel/workqueue.c:2119 >> worker_thread+0x221/0x1850 kernel/workqueue.c:2253 >> kthread+0x363/0x440 kernel/kthread.c:231 >> ret_from_fork+0x2a/0x40 arch/x86/entry/entry_64.S:431 >> > It looks like this is caused by commit > ead666000a5fe34bdc82d61838e4df2d416ea15e ("media: dvb_frontend: only use > kref after initialized"). > > The writing to "fe->frontend_priv" in dvb_frontend.c:156 is a > use-after-free in case the object dvb_frontend *fe is already freed by > the release callback called in line 153. > Only if the demod driver is based on new style i2c_client the memory is > still accessible. > > There are two possible solutions: > 1. Clear fe->frontend_priv earlier (before line 153). > 2. Do not clear fe->frontend_priv > > Can you try if the following patch (solution 1) fixes the issue? Hi Matthias, Your patch fixes the issue. Thanks! Tested-by: Andrey Konovalov <andreyknvl@google.com> > > Regards > Matthias > > diff --git a/drivers/media/dvb-core/dvb_frontend.c > b/drivers/media/dvb-core/dvb_frontend.c > index daaf969719e4..f552acdb7d8c 100644 > --- a/drivers/media/dvb-core/dvb_frontend.c > +++ b/drivers/media/dvb-core/dvb_frontend.c > @@ -150,10 +150,11 @@ static void __dvb_frontend_free(struct > dvb_frontend *fe) > > dvb_free_device(fepriv->dvbdev); > > + fe->frontend_priv = NULL; > + > dvb_frontend_invoke_release(fe, fe->ops.release); > > kfree(fepriv); > - fe->frontend_priv = NULL; > } > > static void dvb_frontend_free(struct kref *ref) ^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: usb/media/dtt200u: use-after-free in __dvb_frontend_free 2017-10-23 18:58 ` Matthias Schwarzott 2017-10-24 11:19 ` Andrey Konovalov @ 2017-11-07 10:31 ` Mauro Carvalho Chehab 2017-11-07 12:51 ` Andrey Konovalov 1 sibling, 1 reply; 5+ messages in thread From: Mauro Carvalho Chehab @ 2017-11-07 10:31 UTC (permalink / raw) To: Matthias Schwarzott, Andrey Konovalov Cc: Mauro Carvalho Chehab, Max Kellermann, linux-media, LKML, Dmitry Vyukov, Kostya Serebryany, syzkaller Em Mon, 23 Oct 2017 20:58:09 +0200 Matthias Schwarzott <zzam@gentoo.org> escreveu: > Am 23.10.2017 um 16:41 schrieb Andrey Konovalov: > > Hi! > > > > I've got the following report while fuzzing the kernel with syzkaller. > > > > On commit 3e0cc09a3a2c40ec1ffb6b4e12da86e98feccb11 (4.14-rc5+). > > > > dvb-usb: found a 'WideView WT-220U PenType Receiver (based on ZL353)' > > in warm state. > > dvb-usb: bulk message failed: -22 (2/1102416563) > > dvb-usb: will use the device's hardware PID filter (table count: 15). > > dvbdev: DVB: registering new adapter (WideView WT-220U PenType > > Receiver (based on ZL353)) > > usb 1-1: media controller created > > dvbdev: dvb_create_media_entity: media entity 'dvb-demux' registered. > > usb 1-1: DVB: registering adapter 0 frontend 0 (WideView USB DVB-T)... > > dvbdev: dvb_create_media_entity: media entity 'WideView USB DVB-T' registered. > > Registered IR keymap rc-dtt200u > > rc rc1: IR-receiver inside an USB DVB receiver as > > /devices/platform/dummy_hcd.0/usb1/1-1/rc/rc1 > > input: IR-receiver inside an USB DVB receiver as > > /devices/platform/dummy_hcd.0/usb1/1-1/rc/rc1/input9 > > dvb-usb: schedule remote query interval to 300 msecs. > > dvb-usb: WideView WT-220U PenType Receiver (based on ZL353) > > successfully initialized and connected. > > dvb-usb: bulk message failed: -22 (1/1807119384) > > dvb-usb: error -22 while querying for an remote control event. > > dvb-usb: bulk message failed: -22 (1/1807119384) > > dvb-usb: error -22 while querying for an remote control event. > > dvb-usb: bulk message failed: -22 (1/1807119384) > > dvb-usb: error -22 while querying for an remote control event. > > dvb-usb: bulk message failed: -22 (1/1807119384) > > dvb-usb: error -22 while querying for an remote control event. > > dvb-usb: bulk message failed: -22 (1/1807119384) > > dvb-usb: error -22 while querying for an remote control event. > > dvb-usb: bulk message failed: -22 (1/1807119384) > > dvb-usb: error -22 while querying for an remote control event. > > usb 1-1: USB disconnect, device number 2 > > ================================================================== > > BUG: KASAN: use-after-free in __dvb_frontend_free+0x113/0x120 > > Write of size 8 at addr ffff880067d45a00 by task kworker/0:1/24 > > > > CPU: 0 PID: 24 Comm: kworker/0:1 Not tainted 4.14.0-rc5-43687-g06ab8a23e0e6 #545 > > Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011 > > Workqueue: usb_hub_wq hub_event > > Call Trace: > > __dump_stack lib/dump_stack.c:16 > > dump_stack+0x292/0x395 lib/dump_stack.c:52 > > print_address_description+0x78/0x280 mm/kasan/report.c:252 > > kasan_report_error mm/kasan/report.c:351 > > kasan_report+0x23d/0x350 mm/kasan/report.c:409 > > __asan_report_store8_noabort+0x1c/0x20 mm/kasan/report.c:435 > > __dvb_frontend_free+0x113/0x120 drivers/media/dvb-core/dvb_frontend.c:156 > > dvb_frontend_put+0x59/0x70 drivers/media/dvb-core/dvb_frontend.c:176 > > dvb_frontend_detach+0x120/0x150 drivers/media/dvb-core/dvb_frontend.c:2803 > > dvb_usb_adapter_frontend_exit+0xd6/0x160 > > drivers/media/usb/dvb-usb/dvb-usb-dvb.c:340 > > dvb_usb_adapter_exit drivers/media/usb/dvb-usb/dvb-usb-init.c:116 > > dvb_usb_exit+0x9b/0x200 drivers/media/usb/dvb-usb/dvb-usb-init.c:132 > > dvb_usb_device_exit+0xa5/0xf0 drivers/media/usb/dvb-usb/dvb-usb-init.c:295 > > usb_unbind_interface+0x21c/0xa90 drivers/usb/core/driver.c:423 > > __device_release_driver drivers/base/dd.c:861 > > device_release_driver_internal+0x4f1/0x5c0 drivers/base/dd.c:893 > > device_release_driver+0x1e/0x30 drivers/base/dd.c:918 > > bus_remove_device+0x2f4/0x4b0 drivers/base/bus.c:565 > > device_del+0x5c4/0xab0 drivers/base/core.c:1985 > > usb_disable_device+0x1e9/0x680 drivers/usb/core/message.c:1170 > > usb_disconnect+0x260/0x7a0 drivers/usb/core/hub.c:2124 > > hub_port_connect drivers/usb/core/hub.c:4754 > > hub_port_connect_change drivers/usb/core/hub.c:5009 > > port_event drivers/usb/core/hub.c:5115 > > hub_event+0x1318/0x3740 drivers/usb/core/hub.c:5195 > > process_one_work+0xc73/0x1d90 kernel/workqueue.c:2119 > > worker_thread+0x221/0x1850 kernel/workqueue.c:2253 > > kthread+0x363/0x440 kernel/kthread.c:231 > > ret_from_fork+0x2a/0x40 arch/x86/entry/entry_64.S:431 > > > It looks like this is caused by commit > ead666000a5fe34bdc82d61838e4df2d416ea15e ("media: dvb_frontend: only use > kref after initialized"). > > The writing to "fe->frontend_priv" in dvb_frontend.c:156 is a > use-after-free in case the object dvb_frontend *fe is already freed by > the release callback called in line 153. > Only if the demod driver is based on new style i2c_client the memory is > still accessible. > > There are two possible solutions: > 1. Clear fe->frontend_priv earlier (before line 153). > 2. Do not clear fe->frontend_priv > > Can you try if the following patch (solution 1) fixes the issue? The problem with (1) is that drivers may need to use frontend_priv on their own release callbacks. So, I don't think this is the right fix. I guess option (2) is the best one here. Andrey, Could you please test the enclosed patch? Thanks! Mauro dvb_frontend: don't use-after-free the frontend struct dvb_frontend_invoke_release() may free the frontend struct. So, we can't update it anymore after calling it. That's OK, as __dvb_frontend_free() is called only when the krefs are zeroed, so nobody is using it anymore. Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com> diff --git a/drivers/media/dvb-core/dvb_frontend.c b/drivers/media/dvb-core/dvb_frontend.c index daaf969719e4..80191a15cd89 100644 --- a/drivers/media/dvb-core/dvb_frontend.c +++ b/drivers/media/dvb-core/dvb_frontend.c @@ -153,7 +153,6 @@ static void __dvb_frontend_free(struct dvb_frontend *fe) dvb_frontend_invoke_release(fe, fe->ops.release); kfree(fepriv); - fe->frontend_priv = NULL; } static void dvb_frontend_free(struct kref *ref) Thanks, Mauro ^ permalink raw reply related [flat|nested] 5+ messages in thread
* Re: usb/media/dtt200u: use-after-free in __dvb_frontend_free 2017-11-07 10:31 ` Mauro Carvalho Chehab @ 2017-11-07 12:51 ` Andrey Konovalov 0 siblings, 0 replies; 5+ messages in thread From: Andrey Konovalov @ 2017-11-07 12:51 UTC (permalink / raw) To: Mauro Carvalho Chehab Cc: Matthias Schwarzott, Mauro Carvalho Chehab, Max Kellermann, linux-media, LKML, Dmitry Vyukov, Kostya Serebryany, syzkaller On Tue, Nov 7, 2017 at 11:31 AM, Mauro Carvalho Chehab <mchehab@s-opensource.com> wrote: > Em Mon, 23 Oct 2017 20:58:09 +0200 > Matthias Schwarzott <zzam@gentoo.org> escreveu: > >> Am 23.10.2017 um 16:41 schrieb Andrey Konovalov: >> > Hi! >> > >> > I've got the following report while fuzzing the kernel with syzkaller. >> > >> > On commit 3e0cc09a3a2c40ec1ffb6b4e12da86e98feccb11 (4.14-rc5+). >> > >> > dvb-usb: found a 'WideView WT-220U PenType Receiver (based on ZL353)' >> > in warm state. >> > dvb-usb: bulk message failed: -22 (2/1102416563) >> > dvb-usb: will use the device's hardware PID filter (table count: 15). >> > dvbdev: DVB: registering new adapter (WideView WT-220U PenType >> > Receiver (based on ZL353)) >> > usb 1-1: media controller created >> > dvbdev: dvb_create_media_entity: media entity 'dvb-demux' registered. >> > usb 1-1: DVB: registering adapter 0 frontend 0 (WideView USB DVB-T)... >> > dvbdev: dvb_create_media_entity: media entity 'WideView USB DVB-T' registered. >> > Registered IR keymap rc-dtt200u >> > rc rc1: IR-receiver inside an USB DVB receiver as >> > /devices/platform/dummy_hcd.0/usb1/1-1/rc/rc1 >> > input: IR-receiver inside an USB DVB receiver as >> > /devices/platform/dummy_hcd.0/usb1/1-1/rc/rc1/input9 >> > dvb-usb: schedule remote query interval to 300 msecs. >> > dvb-usb: WideView WT-220U PenType Receiver (based on ZL353) >> > successfully initialized and connected. >> > dvb-usb: bulk message failed: -22 (1/1807119384) >> > dvb-usb: error -22 while querying for an remote control event. >> > dvb-usb: bulk message failed: -22 (1/1807119384) >> > dvb-usb: error -22 while querying for an remote control event. >> > dvb-usb: bulk message failed: -22 (1/1807119384) >> > dvb-usb: error -22 while querying for an remote control event. >> > dvb-usb: bulk message failed: -22 (1/1807119384) >> > dvb-usb: error -22 while querying for an remote control event. >> > dvb-usb: bulk message failed: -22 (1/1807119384) >> > dvb-usb: error -22 while querying for an remote control event. >> > dvb-usb: bulk message failed: -22 (1/1807119384) >> > dvb-usb: error -22 while querying for an remote control event. >> > usb 1-1: USB disconnect, device number 2 >> > ================================================================== >> > BUG: KASAN: use-after-free in __dvb_frontend_free+0x113/0x120 >> > Write of size 8 at addr ffff880067d45a00 by task kworker/0:1/24 >> > >> > CPU: 0 PID: 24 Comm: kworker/0:1 Not tainted 4.14.0-rc5-43687-g06ab8a23e0e6 #545 >> > Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011 >> > Workqueue: usb_hub_wq hub_event >> > Call Trace: >> > __dump_stack lib/dump_stack.c:16 >> > dump_stack+0x292/0x395 lib/dump_stack.c:52 >> > print_address_description+0x78/0x280 mm/kasan/report.c:252 >> > kasan_report_error mm/kasan/report.c:351 >> > kasan_report+0x23d/0x350 mm/kasan/report.c:409 >> > __asan_report_store8_noabort+0x1c/0x20 mm/kasan/report.c:435 >> > __dvb_frontend_free+0x113/0x120 drivers/media/dvb-core/dvb_frontend.c:156 >> > dvb_frontend_put+0x59/0x70 drivers/media/dvb-core/dvb_frontend.c:176 >> > dvb_frontend_detach+0x120/0x150 drivers/media/dvb-core/dvb_frontend.c:2803 >> > dvb_usb_adapter_frontend_exit+0xd6/0x160 >> > drivers/media/usb/dvb-usb/dvb-usb-dvb.c:340 >> > dvb_usb_adapter_exit drivers/media/usb/dvb-usb/dvb-usb-init.c:116 >> > dvb_usb_exit+0x9b/0x200 drivers/media/usb/dvb-usb/dvb-usb-init.c:132 >> > dvb_usb_device_exit+0xa5/0xf0 drivers/media/usb/dvb-usb/dvb-usb-init.c:295 >> > usb_unbind_interface+0x21c/0xa90 drivers/usb/core/driver.c:423 >> > __device_release_driver drivers/base/dd.c:861 >> > device_release_driver_internal+0x4f1/0x5c0 drivers/base/dd.c:893 >> > device_release_driver+0x1e/0x30 drivers/base/dd.c:918 >> > bus_remove_device+0x2f4/0x4b0 drivers/base/bus.c:565 >> > device_del+0x5c4/0xab0 drivers/base/core.c:1985 >> > usb_disable_device+0x1e9/0x680 drivers/usb/core/message.c:1170 >> > usb_disconnect+0x260/0x7a0 drivers/usb/core/hub.c:2124 >> > hub_port_connect drivers/usb/core/hub.c:4754 >> > hub_port_connect_change drivers/usb/core/hub.c:5009 >> > port_event drivers/usb/core/hub.c:5115 >> > hub_event+0x1318/0x3740 drivers/usb/core/hub.c:5195 >> > process_one_work+0xc73/0x1d90 kernel/workqueue.c:2119 >> > worker_thread+0x221/0x1850 kernel/workqueue.c:2253 >> > kthread+0x363/0x440 kernel/kthread.c:231 >> > ret_from_fork+0x2a/0x40 arch/x86/entry/entry_64.S:431 >> > >> It looks like this is caused by commit >> ead666000a5fe34bdc82d61838e4df2d416ea15e ("media: dvb_frontend: only use >> kref after initialized"). >> >> The writing to "fe->frontend_priv" in dvb_frontend.c:156 is a >> use-after-free in case the object dvb_frontend *fe is already freed by >> the release callback called in line 153. >> Only if the demod driver is based on new style i2c_client the memory is >> still accessible. >> >> There are two possible solutions: >> 1. Clear fe->frontend_priv earlier (before line 153). >> 2. Do not clear fe->frontend_priv >> >> Can you try if the following patch (solution 1) fixes the issue? Hi Mauro, This patch also fixes the issue. Thanks! Tested-by: Andrey Konovalov <andreyknvl@google.com> > > The problem with (1) is that drivers may need to use frontend_priv > on their own release callbacks. > > So, I don't think this is the right fix. > > I guess option (2) is the best one here. > > Andrey, > > Could you please test the enclosed patch? > > Thanks! > Mauro > > dvb_frontend: don't use-after-free the frontend struct > > dvb_frontend_invoke_release() may free the frontend struct. > So, we can't update it anymore after calling it. > That's OK, as __dvb_frontend_free() is called only when the > krefs are zeroed, so nobody is using it anymore. > > Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com> > > > diff --git a/drivers/media/dvb-core/dvb_frontend.c b/drivers/media/dvb-core/dvb_frontend.c > index daaf969719e4..80191a15cd89 100644 > --- a/drivers/media/dvb-core/dvb_frontend.c > +++ b/drivers/media/dvb-core/dvb_frontend.c > @@ -153,7 +153,6 @@ static void __dvb_frontend_free(struct dvb_frontend *fe) > dvb_frontend_invoke_release(fe, fe->ops.release); > > kfree(fepriv); > - fe->frontend_priv = NULL; > } > > static void dvb_frontend_free(struct kref *ref) > > > Thanks, > Mauro ^ permalink raw reply [flat|nested] 5+ messages in thread
end of thread, other threads:[~2017-11-07 12:51 UTC | newest] Thread overview: 5+ messages (download: mbox.gz / follow: Atom feed) -- links below jump to the message on this page -- 2017-10-23 14:41 usb/media/dtt200u: use-after-free in __dvb_frontend_free Andrey Konovalov 2017-10-23 18:58 ` Matthias Schwarzott 2017-10-24 11:19 ` Andrey Konovalov 2017-11-07 10:31 ` Mauro Carvalho Chehab 2017-11-07 12:51 ` Andrey Konovalov
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