On Tue, Aug 13, 2019 at 6:27 AM Hillf Danton <hdanton@xxxxxxxx> wrote: > > [respin with the mess in Cc list cleaned up] > > On Mon, 12 Aug 2019 06:03:01 -0700 > > Hello, > > > > syzbot has tested the proposed patch but the reproducer still triggered crash: > > KASAN: invalid-free in hcd_buffer_free > > > > usb 5-1: USB disconnect, device number 2 > > ================================================================== > > BUG: KASAN: double-free or invalid-free in hcd_buffer_free+0x199/0x260 > > drivers/usb/core/buffer.c:165 > > > > CPU: 0 PID: 1745 Comm: kworker/0:2 Not tainted 5.3.0-rc2+ #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+0x6a/0x32c mm/kasan/report.c:351 > > kasan_report_invalid_free+0x61/0xa0 mm/kasan/report.c:444 > > __kasan_slab_free+0x162/0x180 mm/kasan/common.c:428 > > 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 > > hcd_buffer_free+0x199/0x260 drivers/usb/core/buffer.c:165 > > usb_free_coherent+0x67/0x80 drivers/usb/core/usb.c:932 > > hid_free_buffers.isra.0+0x94/0x290 drivers/hid/usbhid/hid-core.c:964 > > usbhid_stop+0x308/0x450 drivers/hid/usbhid/hid-core.c:1224 > > logi_dj_remove+0x107/0x210 drivers/hid/hid-logitech-dj.c:1797 > > hid_device_remove+0xed/0x240 drivers/hid/hid-core.c:2242 > > __device_release_driver drivers/base/dd.c:1118 [inline] > > device_release_driver_internal+0x206/0x4c0 drivers/base/dd.c:1151 > > bus_remove_device+0x2dc/0x4a0 drivers/base/bus.c:556 > > device_del+0x420/0xb10 drivers/base/core.c:2288 > > hid_remove_device drivers/hid/hid-core.c:2413 [inline] > > hid_destroy_device+0xe1/0x150 drivers/hid/hid-core.c:2432 > > usbhid_disconnect+0xad/0xd0 drivers/hid/usbhid/hid-core.c:1414 > > 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 1745: > > 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 > > kmalloc include/linux/slab.h:557 [inline] > > hcd_buffer_alloc+0x1ca/0x290 drivers/usb/core/buffer.c:135 > > usb_alloc_coherent+0x5d/0x80 drivers/usb/core/usb.c:910 > > hid_alloc_buffers drivers/hid/usbhid/hid-core.c:846 [inline] > > usbhid_start+0x60b/0x22f0 drivers/hid/usbhid/hid-core.c:1075 > > hid_hw_start+0x5d/0x130 drivers/hid/hid-core.c:1976 > > logi_dj_probe+0x808/0xcd7 drivers/hid/hid-logitech-dj.c:1703 > > hid_device_probe+0x2be/0x3f0 drivers/hid/hid-core.c:2209 > > 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 > > hid_add_device+0x33c/0x990 drivers/hid/hid-core.c:2365 > > usbhid_probe+0xa81/0xfa0 drivers/hid/usbhid/hid-core.c:1386 > > 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 1745: > > 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 > > hcd_buffer_free+0x199/0x260 drivers/usb/core/buffer.c:165 > > usb_free_coherent+0x67/0x80 drivers/usb/core/usb.c:932 > > hid_free_buffers.isra.0+0x94/0x290 drivers/hid/usbhid/hid-core.c:964 > > usbhid_stop+0x308/0x450 drivers/hid/usbhid/hid-core.c:1224 > > usbhid_disconnect+0xa5/0xd0 drivers/hid/usbhid/hid-core.c:1413 > > 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 > > > > The buggy address belongs to the object at ffff8881d5875500 > > which belongs to the cache kmalloc-4k of size 4096 > > The buggy address is located 0 bytes inside of > > 4096-byte region [ffff8881d5875500, ffff8881d5876500) > > The buggy address belongs to the page: > > page:ffffea0007561c00 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: > > ffff8881d5875400: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc > > ffff8881d5875480: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc > > > ffff8881d5875500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb > > ^ > > ffff8881d5875580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb > > ffff8881d5875600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb > > ================================================================== > > > > > > Tested on: > > > > commit: 7f7867ff 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=13833b9a600000 > > kernel config: https://syzkaller.appspot.com/x/.config?x=792eb47789f57810 > > compiler: gcc (GCC) 9.0.0 20181231 (experimental) > > patch: https://syzkaller.appspot.com/x/patch.diff?x=167d2a0e600000 > > Followup of commit e3e14de50dff ("HID: fix start/stop cycle in usbhid driver") > > --- a/drivers/hid/usbhid/hid-core.c > +++ b/drivers/hid/usbhid/hid-core.c > @@ -1214,6 +1214,8 @@ static void usbhid_stop(struct hid_devic > > hid->claimed = 0; > > + if (!usbhid->urbin) /* freeing buffers only once */ > + return; I have not read all the code, but the last report was a double-free, which suggests that usbhid->urbin is actually not reset to NULL, so this check won't help. Potentially we need both this check and reset the fields to NULL after freeing. > usb_free_urb(usbhid->urbin); > usb_free_urb(usbhid->urbctrl); > usb_free_urb(usbhid->urbout);
