On Tue, Jul 23, 2019 at 2:48 PM syzbot wrote: > > Hello, > > syzbot found the following crash on: > > HEAD commit: 6a3599ce 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=107e7264600000 > kernel config: https://syzkaller.appspot.com/x/.config?x=700ca426ab83faae > dashboard link: https://syzkaller.appspot.com/bug?extid=ded1794a717e3b235226 > compiler: gcc (GCC) 9.0.0 20181231 (experimental) > syz repro: https://syzkaller.appspot.com/x/repro.syz?x=13b98b4c600000 > C reproducer: https://syzkaller.appspot.com/x/repro.c?x=1619b07c600000 > > IMPORTANT: if you fix the bug, please add the following tag to the commit: > Reported-by: syzbot+ded1794a717e3b235226@syzkaller.appspotmail.com > > ================================================================== > BUG: KASAN: use-after-free in hidraw_ioctl+0x609/0xaf0 > /drivers/hid/hidraw.c:380 > Read of size 4 at addr ffff8881d549a118 by task syz-executor073/2445 > > CPU: 0 PID: 2445 Comm: syz-executor073 Not tainted 5.2.0-rc6+ #15 > Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS > Google 01/01/2011 > 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 > hidraw_ioctl+0x609/0xaf0 /drivers/hid/hidraw.c:380 > vfs_ioctl /fs/ioctl.c:46 [inline] > file_ioctl /fs/ioctl.c:509 [inline] > do_vfs_ioctl+0xcda/0x12e0 /fs/ioctl.c:696 > ksys_ioctl+0x9b/0xc0 /fs/ioctl.c:713 > __do_sys_ioctl /fs/ioctl.c:720 [inline] > __se_sys_ioctl /fs/ioctl.c:718 [inline] > __x64_sys_ioctl+0x6f/0xb0 /fs/ioctl.c:718 > do_syscall_64+0xb7/0x560 /arch/x86/entry/common.c:301 > entry_SYSCALL_64_after_hwframe+0x49/0xbe > RIP: 0033:0x451fd9 > Code: e8 ec e7 ff ff 48 83 c4 18 c3 0f 1f 80 00 00 00 00 48 89 f8 48 89 f7 > 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff > ff 0f 83 5b cb fb ff c3 66 2e 0f 1f 84 00 00 00 00 > RSP: 002b:00007f3144bd5ce8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 > RAX: ffffffffffffffda RBX: 00000000006e3c88 RCX: 0000000000451fd9 > RDX: 00000000200015c0 RSI: 0000000080044801 RDI: 0000000000000005 > RBP: 00000000006e3c80 R08: 0000000000000000 R09: 0000000000000000 > R10: 0000000000000000 R11: 0000000000000246 R12: 00000000006e3c8c > R13: 00007ffc64ba492f R14: 00007f3144bd69c0 R15: 0000000000000002 > > Allocated by task 5: > 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] > hid_allocate_device+0x3e/0x480 /drivers/hid/hid-core.c:2389 > usbhid_probe+0x23e/0xfa0 /drivers/hid/usbhid/hid-core.c:1321 > 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+0x6a4/0xe61 /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+0x1abd/0x3550 /drivers/usb/core/hub.c:5441 > process_one_work+0x905/0x1570 /kernel/workqueue.c:2269 > worker_thread+0x96/0xe20 /kernel/workqueue.c:2415 > kthread+0x30b/0x410 /kernel/kthread.c:255 > ret_from_fork+0x24/0x30 /arch/x86/entry/entry_64.S:352 > > Freed by task 1781: > 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+0xd7/0x280 /mm/slub.c:3949 > device_release+0x71/0x200 /drivers/base/core.c:1064 > kobject_cleanup /lib/kobject.c:691 [inline] > kobject_release /lib/kobject.c:720 [inline] > kref_put /./include/linux/kref.h:65 [inline] > kobject_put+0x171/0x280 /lib/kobject.c:737 > put_device+0x1b/0x30 /drivers/base/core.c:2210 > usbhid_disconnect+0x90/0xd0 /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:1081 [inline] > device_release_driver_internal+0x404/0x4c0 /drivers/base/dd.c:1112 > bus_remove_device+0x2dc/0x4a0 /drivers/base/bus.c:556 > device_del+0x460/0xb80 /drivers/base/core.c:2274 > usb_disable_device+0x211/0x690 /drivers/usb/core/message.c:1237 > usb_disconnect+0x284/0x830 /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+0x13bd/0x3550 /drivers/usb/core/hub.c:5441 > process_one_work+0x905/0x1570 /kernel/workqueue.c:2269 > worker_thread+0x96/0xe20 /kernel/workqueue.c:2415 > 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 object at ffff8881d549a100 > which belongs to the cache kmalloc-8k of size 8192 > The buggy address is located 24 bytes inside of > 8192-byte region [ffff8881d549a100, ffff8881d549c100) > The buggy address belongs to the page: > page:ffffea0007552600 refcount:1 mapcount:0 mapping:ffff8881dac02400 > index:0x0 compound_mapcount: 0 > flags: 0x200000000010200(slab|head) > raw: 0200000000010200 dead000000000100 dead000000000200 ffff8881dac02400 > raw: 0000000000000000 0000000000030003 00000001ffffffff 0000000000000000 > page dumped because: kasan: bad access detected > > Memory state around the buggy address: > ffff8881d549a000: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc > ffff8881d549a080: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc > > ffff8881d549a100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb > ^ > ffff8881d549a180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb > ffff8881d549a200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb > ================================================================== > > > --- > This bug is generated by a bot. It may contain errors. > See https://goo.gl/tpsmEJ for more information about syzbot. > syzbot engineers can be reached at syzkaller@googlegroups.com. > > syzbot will keep track of this bug report. See: > https://goo.gl/tpsmEJ#status for how to communicate with syzbot. > syzbot can test patches for this bug, for details see: > https://goo.gl/tpsmEJ#testing-patches Trying Alan's fix from another thread here: #syz test: https://github.com/google/kasan.git usb-fuzzer 6a3599ce