On Thu, Aug 8, 2019 at 10:03 AM Hillf Danton wrote: > > > [respin due to "Sender frequency limited" and therefore the Cc list once > cut short:(] > > Tue, 06 Aug 2019 06:18:08 -0700 > > 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+c58e976e022432ee60b4@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 > > ================================================================== > > 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); > -- > #syz test: https://github.com/google/kasan.git e96407b4