On Tue, Aug 13, 2019 at 3:16 PM syzbot <syzbot+67b2bd0e34f952d0321e@xxxxxxxxxxxxxxxxxxxxxxxxx> wrote: > > Hello, > > syzbot has tested the proposed patch but the reproducer still triggered > crash: > KASAN: use-after-free Read in hso_free_interface > > ================================================================== > BUG: KASAN: use-after-free in hso_free_interface+0x3f2/0x4f0 > drivers/net/usb/hso.c:3108 > Read of size 8 at addr ffff8881d112d998 by task kworker/0:1/12 > > CPU: 0 PID: 12 Comm: kworker/0:1 Not tainted 5.2.0-rc1+ #1 > 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 > hso_free_interface+0x3f2/0x4f0 drivers/net/usb/hso.c:3108 > hso_probe+0x362/0x1a50 drivers/net/usb/hso.c:2963 > usb_probe_interface+0x30b/0x7a0 drivers/usb/core/driver.c:361 > really_probe+0x287/0x660 drivers/base/dd.c:509 > driver_probe_device+0x104/0x210 drivers/base/dd.c:670 > __device_attach_driver+0x1c4/0x230 drivers/base/dd.c:777 > bus_for_each_drv+0x15e/0x1e0 drivers/base/bus.c:454 > __device_attach+0x217/0x360 drivers/base/dd.c:843 > bus_probe_device+0x1e6/0x290 drivers/base/bus.c:514 > device_add+0xae6/0x1700 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+0xa2/0x100 drivers/usb/core/driver.c:266 > really_probe+0x287/0x660 drivers/base/dd.c:509 > driver_probe_device+0x104/0x210 drivers/base/dd.c:670 > __device_attach_driver+0x1c4/0x230 drivers/base/dd.c:777 > bus_for_each_drv+0x15e/0x1e0 drivers/base/bus.c:454 > __device_attach+0x217/0x360 drivers/base/dd.c:843 > bus_probe_device+0x1e6/0x290 drivers/base/bus.c:514 > device_add+0xae6/0x1700 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+0x1adc/0x35a0 drivers/usb/core/hub.c:5432 > process_one_work+0x90a/0x1580 kernel/workqueue.c:2268 > worker_thread+0x96/0xe20 kernel/workqueue.c:2414 > kthread+0x30e/0x420 kernel/kthread.c:254 > ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:352 > > Allocated by task 12: > save_stack+0x1b/0x80 mm/kasan/common.c:71 > set_track mm/kasan/common.c:79 [inline] > __kasan_kmalloc mm/kasan/common.c:489 [inline] > __kasan_kmalloc.constprop.0+0xbf/0xd0 mm/kasan/common.c:462 > kmalloc include/linux/slab.h:547 [inline] > kzalloc include/linux/slab.h:742 [inline] > hso_create_device+0x43/0x390 drivers/net/usb/hso.c:2336 > hso_create_bulk_serial_device drivers/net/usb/hso.c:2617 [inline] > hso_probe+0xbb0/0x1a50 drivers/net/usb/hso.c:2948 > usb_probe_interface+0x30b/0x7a0 drivers/usb/core/driver.c:361 > really_probe+0x287/0x660 drivers/base/dd.c:509 > driver_probe_device+0x104/0x210 drivers/base/dd.c:670 > __device_attach_driver+0x1c4/0x230 drivers/base/dd.c:777 > bus_for_each_drv+0x15e/0x1e0 drivers/base/bus.c:454 > __device_attach+0x217/0x360 drivers/base/dd.c:843 > bus_probe_device+0x1e6/0x290 drivers/base/bus.c:514 > device_add+0xae6/0x1700 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+0xa2/0x100 drivers/usb/core/driver.c:266 > really_probe+0x287/0x660 drivers/base/dd.c:509 > driver_probe_device+0x104/0x210 drivers/base/dd.c:670 > __device_attach_driver+0x1c4/0x230 drivers/base/dd.c:777 > bus_for_each_drv+0x15e/0x1e0 drivers/base/bus.c:454 > __device_attach+0x217/0x360 drivers/base/dd.c:843 > bus_probe_device+0x1e6/0x290 drivers/base/bus.c:514 > device_add+0xae6/0x1700 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+0x1adc/0x35a0 drivers/usb/core/hub.c:5432 > process_one_work+0x90a/0x1580 kernel/workqueue.c:2268 > worker_thread+0x96/0xe20 kernel/workqueue.c:2414 > kthread+0x30e/0x420 kernel/kthread.c:254 > ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:352 > > Freed by task 12: > save_stack+0x1b/0x80 mm/kasan/common.c:71 > set_track mm/kasan/common.c:79 [inline] > __kasan_slab_free+0x130/0x180 mm/kasan/common.c:451 > slab_free_hook mm/slub.c:1421 [inline] > slab_free_freelist_hook mm/slub.c:1448 [inline] > slab_free mm/slub.c:2994 [inline] > kfree+0xd7/0x290 mm/slub.c:3949 > hso_create_bulk_serial_device drivers/net/usb/hso.c:2687 [inline] > hso_probe+0x13c6/0x1a50 drivers/net/usb/hso.c:2948 > usb_probe_interface+0x30b/0x7a0 drivers/usb/core/driver.c:361 > really_probe+0x287/0x660 drivers/base/dd.c:509 > driver_probe_device+0x104/0x210 drivers/base/dd.c:670 > __device_attach_driver+0x1c4/0x230 drivers/base/dd.c:777 > bus_for_each_drv+0x15e/0x1e0 drivers/base/bus.c:454 > __device_attach+0x217/0x360 drivers/base/dd.c:843 > bus_probe_device+0x1e6/0x290 drivers/base/bus.c:514 > device_add+0xae6/0x1700 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+0xa2/0x100 drivers/usb/core/driver.c:266 > really_probe+0x287/0x660 drivers/base/dd.c:509 > driver_probe_device+0x104/0x210 drivers/base/dd.c:670 > __device_attach_driver+0x1c4/0x230 drivers/base/dd.c:777 > bus_for_each_drv+0x15e/0x1e0 drivers/base/bus.c:454 > __device_attach+0x217/0x360 drivers/base/dd.c:843 > bus_probe_device+0x1e6/0x290 drivers/base/bus.c:514 > device_add+0xae6/0x1700 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+0x1adc/0x35a0 drivers/usb/core/hub.c:5432 > process_one_work+0x90a/0x1580 kernel/workqueue.c:2268 > worker_thread+0x96/0xe20 kernel/workqueue.c:2414 > kthread+0x30e/0x420 kernel/kthread.c:254 > ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:352 > > The buggy address belongs to the object at ffff8881d112d900 > which belongs to the cache kmalloc-512 of size 512 > The buggy address is located 152 bytes inside of > 512-byte region [ffff8881d112d900, ffff8881d112db00) > The buggy address belongs to the page: > page:ffffea0007444b00 refcount:1 mapcount:0 mapping:ffff8881dac02c00 > index:0x0 compound_mapcount: 0 > flags: 0x200000000010200(slab|head) > raw: 0200000000010200 ffffea000744ea80 0000000400000004 ffff8881dac02c00 > raw: 0000000000000000 00000000000c000c 00000001ffffffff 0000000000000000 > page dumped because: kasan: bad access detected > > Memory state around the buggy address: > ffff8881d112d880: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc > ffff8881d112d900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb > > ffff8881d112d980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb > ^ > ffff8881d112da00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb > ffff8881d112da80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb > ================================================================== > > > Tested on: > > commit: 69bbe8c7 usb-fuzzer: main usb gadget fuzzer driver > git tree: https://github.com/google/kasan.git > console output: https://syzkaller.appspot.com/x/log.txt?x=14e6156a600000 > kernel config: https://syzkaller.appspot.com/x/.config?x=c309d28e15db39c5 > compiler: gcc (GCC) 9.0.0 20181231 (experimental) > patch: https://syzkaller.appspot.com/x/patch.diff?x=1715ad4a600000 > This bug looks very similar to the "KASAN: use-after-free Read in device_del" one, but the fix from that thread doesn't work here.