On Thu, Nov 23, 2017 at 8:25 AM, Matthias Schwarzott <zzam@xxxxxxxxxx> wrote: > Am 21.11.2017 um 14:51 schrieb Andrey Konovalov: >> Hi! >> > Hi Andrey, > >> I've got the following report while fuzzing the kernel with syzkaller. >> >> On commit e1d1ea549b57790a3d8cf6300e6ef86118d692a3 (4.15-rc1). >> >> em28xx 1-1:9.0: Disconnecting >> tc90522 1-0015: Toshiba TC90522 attached. >> qm1d1c0042 2-0061: Sharp QM1D1C0042 attached. >> dvbdev: DVB: registering new adapter (1-1:9.0) >> em28xx 1-1:9.0: DVB: registering adapter 0 frontend 0 (Toshiba TC90522 >> ISDB-S module)... >> dvbdev: dvb_create_media_entity: media entity 'Toshiba TC90522 ISDB-S >> module' registered. >> dvbdev: dvb_create_media_entity: media entity 'dvb-demux' registered. >> em28xx 1-1:9.0: DVB extension successfully initialized >> em28xx 1-1:9.0: Remote control support is not available for this card. >> em28xx 1-1:9.0: Closing DVB extension >> ================================================================== >> BUG: KASAN: use-after-free in dvb_unregister_frontend+0x8f/0xa0 >> Read of size 8 at addr ffff880067853628 by task kworker/0:3/3182 >> >> CPU: 0 PID: 3182 Comm: kworker/0:3 Not tainted 4.14.0-57501-g9284d204d604 #119 >> 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:17 >> dump_stack+0xe1/0x157 lib/dump_stack.c:53 >> print_address_description+0x71/0x234 mm/kasan/report.c:252 >> kasan_report_error mm/kasan/report.c:351 >> kasan_report+0x173/0x270 mm/kasan/report.c:409 >> __asan_report_load8_noabort+0x19/0x20 mm/kasan/report.c:430 >> dvb_unregister_frontend+0x8f/0xa0 drivers/media/dvb-core/dvb_frontend.c:2768 >> em28xx_unregister_dvb drivers/media/usb/em28xx/em28xx-dvb.c:1122 >> em28xx_dvb_fini+0x62d/0x8e0 drivers/media/usb/em28xx/em28xx-dvb.c:2129 >> em28xx_close_extension+0x71/0x220 drivers/media/usb/em28xx/em28xx-core.c:1122 >> em28xx_usb_disconnect+0xd7/0x130 drivers/media/usb/em28xx/em28xx-cards.c:3763 >> usb_unbind_interface+0x1b6/0x950 drivers/usb/core/driver.c:423 >> __device_release_driver drivers/base/dd.c:870 >> device_release_driver_internal+0x563/0x630 drivers/base/dd.c:903 >> device_release_driver+0x1e/0x30 drivers/base/dd.c:928 >> bus_remove_device+0x2fc/0x4b0 drivers/base/bus.c:565 >> device_del+0x39f/0xa70 drivers/base/core.c:1984 >> usb_disable_device+0x223/0x710 drivers/usb/core/message.c:1205 >> usb_disconnect+0x285/0x7f0 drivers/usb/core/hub.c:2205 >> hub_port_connect drivers/usb/core/hub.c:4851 >> hub_port_connect_change drivers/usb/core/hub.c:5106 >> port_event drivers/usb/core/hub.c:5212 >> hub_event_impl+0x10f0/0x3440 drivers/usb/core/hub.c:5324 >> hub_event+0x38/0x50 drivers/usb/core/hub.c:5222 >> process_one_work+0x944/0x15f0 kernel/workqueue.c:2112 >> worker_thread+0xef/0x10d0 kernel/workqueue.c:2246 >> kthread+0x367/0x420 kernel/kthread.c:238 >> ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:437 >> > > this looks similar to the oops fixed by this patch: > > https://patchwork.linuxtv.org/patch/45219/ > > Could you try if it fixes your case also? Hi Matthias! Yes, it does fixes the crash for me. Thanks! > > Regards > Matthias
