• Sean Young's avatar
    media: dvb-frontends: use ida for pll number · 9df9652b
    Sean Young authored
    [ Upstream commit c268e7ad ]
    
    KASAN: global-out-of-bounds Read in dvb_pll_attach
    
    Syzbot reported global-out-of-bounds Read in dvb_pll_attach, while
    accessing id[dvb_pll_devcount], because dvb_pll_devcount was 65,
    that is more than size of 'id' which is DVB_PLL_MAX(64).
    
    Rather than increasing dvb_pll_devcount every time, use ida so that
    numbers are allocated correctly. This does mean that no more than
    64 devices can be attached at the same time, but this is more than
    sufficient.
    
    usb 1-1: dvb_usb_v2: will pass the complete MPEG2 transport stream to the
    software demuxer
    dvbdev: DVB: registering new adapter (774 Friio White ISDB-T USB2.0)
    usb 1-1: media controller created
    dvbdev: dvb_create_media_entity: media entity 'dvb-demux' registered.
    tc90522 0-0018: Toshiba TC90522 attached.
    usb 1-1: DVB: registering adapter 0 frontend 0 (Toshiba TC90522 ISDB-T
    module)...
    dvbdev: dvb_create_media_entity: media entity 'Toshiba TC90522 ISDB-T
    module' registered.
    ==================================================================
    BUG: KASAN: global-out-of-bounds in dvb_pll_attach+0x6c5/0x830
    drivers/media/dvb-frontends/dvb-pll.c:798
    Read of size 4 at addr ffffffff89c9e5e0 by task kworker/0:1/12
    
    CPU: 0 PID: 12 Comm: kworker/0:1 Not tainted 5.2.0-rc6+ #13
    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+0x67/0x231 mm/kasan/report.c:188
      __kasan_report.cold+0x1a/0x32 mm/kasan/report.c:317
      kasan_report+0xe/0x20 mm/kasan/common.c:614
      dvb_pll_attach+0x6c5/0x830 drivers/media/dvb-frontends/dvb-pll.c:798
      dvb_pll_probe+0xfe/0x174 drivers/media/dvb-frontends/dvb-pll.c:877
      i2c_device_probe+0x790/0xaa0 drivers/i2c/i2c-core-base.c:389
      really_probe+0x281/0x660 drivers/base/dd.c:509
      driver_probe_device+0x104/0x210 drivers/base/dd.c:670
      __device_attach_driver+0x1c2/0x220 drivers/base/dd.c:777
      bus_for_each_drv+0x15c/0x1e0 drivers/base/bus.c:454
      __device_attach+0x217/0x360 drivers/base/dd.c:843
      bus_probe_device+0x1e4/0x290 drivers/base/bus.c:514
      device_add+0xae6/0x16f0 drivers/base/core.c:2111
      i2c_new_client_device+0x5b3/0xc40 drivers/i2c/i2c-core-base.c:778
      i2c_new_device+0x19/0x50 drivers/i2c/i2c-core-base.c:821
      dvb_module_probe+0xf9/0x220 drivers/media/dvb-core/dvbdev.c:985
      friio_tuner_attach+0x125/0x1d0 drivers/media/usb/dvb-usb-v2/gl861.c:536
      dvb_usbv2_adapter_frontend_init
    drivers/media/usb/dvb-usb-v2/dvb_usb_core.c:675 [inline]
      dvb_usbv2_adapter_init drivers/media/usb/dvb-usb-v2/dvb_usb_core.c:804
    [inline]
      dvb_usbv2_init drivers/media/usb/dvb-usb-v2/dvb_usb_core.c:865 [inline]
      dvb_usbv2_probe.cold+0x24dc/0x255d
    drivers/media/usb/dvb-usb-v2/dvb_usb_core.c:980
      usb_probe_interface+0x305/0x7a0 drivers/usb/core/driver.c:361
      really_probe+0x281/0x660 drivers/base/dd.c:509
      driver_probe_device+0x104/0x210 drivers/base/dd.c:670
      __device_attach_driver+0x1c2/0x220 drivers/base/dd.c:777
      bus_for_each_drv+0x15c/0x1e0 drivers/base/bus.c:454
      __device_attach+0x217/0x360 drivers/base/dd.c:843
      bus_probe_device+0x1e4/0x290 drivers/base/bus.c:514
      device_add+0xae6/0x16f0 drivers/base/core.c:2111
      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+0x281/0x660 drivers/base/dd.c:509
      driver_probe_device+0x104/0x210 drivers/base/dd.c:670
      __device_attach_driver+0x1c2/0x220 drivers/base/dd.c:777
      bus_for_each_drv+0x15c/0x1e0 drivers/base/bus.c:454
      __device_attach+0x217/0x360 drivers/base/dd.c:843
      bus_probe_device+0x1e4/0x290 drivers/base/bus.c:514
      device_add+0xae6/0x16f0 drivers/base/core.c:2111
      usb_new_device.cold+0x8c1/0x1016 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+0x1ada/0x3590 drivers/usb/core/hub.c:5432
      process_one_work+0x905/0x1570 kernel/workqueue.c:2269
      process_scheduled_works kernel/workqueue.c:2331 [inline]
      worker_thread+0x7ab/0xe20 kernel/workqueue.c:2417
      kthread+0x30b/0x410 kernel/kthread.c:255
      ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352
    
    The buggy address belongs to the variable:
      id+0x100/0x120
    
    Memory state around the buggy address:
      ffffffff89c9e480: fa fa fa fa 00 00 fa fa fa fa fa fa 00 00 00 00
      ffffffff89c9e500: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
    > ffffffff89c9e580: 00 00 00 00 00 00 00 00 00 00 00 00 fa fa fa fa
                                                            ^
      ffffffff89c9e600: 04 fa fa fa fa fa fa fa 04 fa fa fa fa fa fa fa
      ffffffff89c9e680: 04 fa fa fa fa fa fa fa 04 fa fa fa fa fa fa fa
    ==================================================================
    
    Reported-by: syzbot+8a8f48672560c8ca59dd@syzkaller.appspotmail.com
    Signed-off-by: default avatarSean Young <sean@mess.org>
    Signed-off-by: default avatarMauro Carvalho Chehab <mchehab+samsung@kernel.org>
    Signed-off-by: default avatarSasha Levin <sashal@kernel.org>
    9df9652b
dvb-pll.c 24.5 KB