From e9f92f267f0c6824dd129d688ac7d1e69a6d6e32 Mon Sep 17 00:00:00 2001 From: vandanabn Date: Wed, 17 Jul 2019 01:34:27 +0530 Subject: [PATCH] media:dvb-frontend: fix syzbot global out of bounds issue. Reported-by: syzbot+8a8f48672560c8ca59dd@syzkaller.appspotmail.com 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 ================================================================== --- drivers/media/dvb-frontends/dvb-pll.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/media/dvb-frontends/dvb-pll.c b/drivers/media/dvb-frontends/dvb-pll.c index ba0c49107bd28b..032f1b2c2e3aaf 100644 --- a/drivers/media/dvb-frontends/dvb-pll.c +++ b/drivers/media/dvb-frontends/dvb-pll.c @@ -787,6 +787,9 @@ struct dvb_frontend *dvb_pll_attach(struct dvb_frontend *fe, int pll_addr, struct dvb_pll_priv *priv = NULL; int ret; const struct dvb_pll_desc *desc; + + if (dvb_pll_devcount > DVB_PLL_MAX-1) + return NULL; b1 = kmalloc(1, GFP_KERNEL); if (!b1)