Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933108AbdIRRdv (ORCPT ); Mon, 18 Sep 2017 13:33:51 -0400 Received: from mail-io0-f181.google.com ([209.85.223.181]:48875 "EHLO mail-io0-f181.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933077AbdIRRds (ORCPT ); Mon, 18 Sep 2017 13:33:48 -0400 X-Google-Smtp-Source: AOwi7QDbG2THo9m+GYQa49D5KVwhgbNQ/C7mIc3nmEL148p0q/fsXfklu2X8/BfYk9STDwKpf2cuyZ8XZjcoDNd6vjk= MIME-Version: 1.0 From: Andrey Konovalov Date: Mon, 18 Sep 2017 19:33:47 +0200 Message-ID: Subject: usb/hid: slab-out-of-bounds read in usbhid_parse To: Jiri Kosina , Benjamin Tissoires , USB list , linux-input@vger.kernel.org, LKML Cc: syzkaller , Dmitry Vyukov , Kostya Serebryany Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 5515 Lines: 117 Hi! I've got the following crash while fuzzing the kernel with syzkaller. On commit ebb2c2437d8008d46796902ff390653822af6cc4 (Sep 18). It seems that there's no proper check on the hdesc->bNumDescriptors value in usbhid_parse(). it iterates over hdesc->desc and accesses hdesc->desc[n] fields, which might be out-of-bounds. ================================================================== BUG: KASAN: slab-out-of-bounds in usbhid_parse+0x9b1/0xa20 Read of size 1 at addr ffff88006c5f8edf by task kworker/1:2/1261 CPU: 1 PID: 1261 Comm: kworker/1:2 Not tainted 4.14.0-rc1-42251-gebb2c2437d80 #169 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011 Workqueue: usb_hub_wq hub_event Call Trace: __dump_stack lib/dump_stack.c:16 dump_stack+0x292/0x395 lib/dump_stack.c:52 print_address_description+0x78/0x280 mm/kasan/report.c:252 kasan_report_error mm/kasan/report.c:351 kasan_report+0x22f/0x340 mm/kasan/report.c:409 __asan_report_load1_noabort+0x19/0x20 mm/kasan/report.c:427 usbhid_parse+0x9b1/0xa20 drivers/hid/usbhid/hid-core.c:1004 hid_add_device+0x16b/0xb30 drivers/hid/hid-core.c:2944 usbhid_probe+0xc28/0x1100 drivers/hid/usbhid/hid-core.c:1369 usb_probe_interface+0x35d/0x8e0 drivers/usb/core/driver.c:361 really_probe drivers/base/dd.c:413 driver_probe_device+0x610/0xa00 drivers/base/dd.c:557 __device_attach_driver+0x230/0x290 drivers/base/dd.c:653 bus_for_each_drv+0x161/0x210 drivers/base/bus.c:463 __device_attach+0x26e/0x3d0 drivers/base/dd.c:710 device_initial_probe+0x1f/0x30 drivers/base/dd.c:757 bus_probe_device+0x1eb/0x290 drivers/base/bus.c:523 device_add+0xd0b/0x1660 drivers/base/core.c:1835 usb_set_configuration+0x104e/0x1870 drivers/usb/core/message.c:1932 generic_probe+0x73/0xe0 drivers/usb/core/generic.c:174 usb_probe_device+0xaf/0xe0 drivers/usb/core/driver.c:266 really_probe drivers/base/dd.c:413 driver_probe_device+0x610/0xa00 drivers/base/dd.c:557 __device_attach_driver+0x230/0x290 drivers/base/dd.c:653 bus_for_each_drv+0x161/0x210 drivers/base/bus.c:463 __device_attach+0x26e/0x3d0 drivers/base/dd.c:710 device_initial_probe+0x1f/0x30 drivers/base/dd.c:757 bus_probe_device+0x1eb/0x290 drivers/base/bus.c:523 device_add+0xd0b/0x1660 drivers/base/core.c:1835 usb_new_device+0x7b8/0x1020 drivers/usb/core/hub.c:2457 hub_port_connect drivers/usb/core/hub.c:4903 hub_port_connect_change drivers/usb/core/hub.c:5009 port_event drivers/usb/core/hub.c:5115 hub_event+0x194d/0x3740 drivers/usb/core/hub.c:5195 process_one_work+0xc7f/0x1db0 kernel/workqueue.c:2119 worker_thread+0x221/0x1850 kernel/workqueue.c:2253 kthread+0x3a1/0x470 kernel/kthread.c:231 ret_from_fork+0x2a/0x40 arch/x86/entry/entry_64.S:431 Allocated by task 1261: save_stack_trace+0x1b/0x20 arch/x86/kernel/stacktrace.c:59 save_stack+0x43/0xd0 mm/kasan/kasan.c:447 set_track mm/kasan/kasan.c:459 kasan_kmalloc+0xad/0xe0 mm/kasan/kasan.c:551 __kmalloc+0x14e/0x310 mm/slub.c:3782 kmalloc ./include/linux/slab.h:498 usb_get_configuration+0x372/0x2a60 drivers/usb/core/config.c:848 usb_enumerate_device drivers/usb/core/hub.c:2290 usb_new_device+0xaae/0x1020 drivers/usb/core/hub.c:2426 hub_port_connect drivers/usb/core/hub.c:4903 hub_port_connect_change drivers/usb/core/hub.c:5009 port_event drivers/usb/core/hub.c:5115 hub_event+0x194d/0x3740 drivers/usb/core/hub.c:5195 process_one_work+0xc7f/0x1db0 kernel/workqueue.c:2119 worker_thread+0x221/0x1850 kernel/workqueue.c:2253 kthread+0x3a1/0x470 kernel/kthread.c:231 ret_from_fork+0x2a/0x40 arch/x86/entry/entry_64.S:431 Freed by task 2927: save_stack_trace+0x1b/0x20 arch/x86/kernel/stacktrace.c:59 save_stack+0x43/0xd0 mm/kasan/kasan.c:447 set_track mm/kasan/kasan.c:459 kasan_slab_free+0x72/0xc0 mm/kasan/kasan.c:524 slab_free_hook mm/slub.c:1390 slab_free_freelist_hook mm/slub.c:1412 slab_free mm/slub.c:2988 kfree+0xf6/0x2f0 mm/slub.c:3919 free_rb_tree_fname+0x8a/0xe0 fs/ext4/dir.c:402 ext4_htree_free_dir_info fs/ext4/dir.c:424 ext4_release_dir+0x49/0x70 fs/ext4/dir.c:622 __fput+0x33e/0x800 fs/file_table.c:210 ____fput+0x1a/0x20 fs/file_table.c:244 task_work_run+0x1af/0x280 kernel/task_work.c:112 tracehook_notify_resume ./include/linux/tracehook.h:191 exit_to_usermode_loop+0x1e1/0x220 arch/x86/entry/common.c:162 prepare_exit_to_usermode arch/x86/entry/common.c:197 syscall_return_slowpath+0x414/0x480 arch/x86/entry/common.c:266 entry_SYSCALL_64_fastpath+0xc0/0xc2 arch/x86/entry/entry_64.S:238 The buggy address belongs to the object at ffff88006c5f8ea0 which belongs to the cache kmalloc-64 of size 64 The buggy address is located 63 bytes inside of 64-byte region [ffff88006c5f8ea0, ffff88006c5f8ee0) The buggy address belongs to the page: page:ffffea0001b17e00 count:1 mapcount:0 mapping: (null) index:0x0 flags: 0x100000000000100(slab) raw: 0100000000000100 0000000000000000 0000000000000000 00000001002a002a raw: ffffea0001a83000 0000001500000015 ffff88006c403800 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff88006c5f8d80: fb fb fb fb fb fb fb fb fc fc fc fc 00 00 00 00 ffff88006c5f8e00: 00 fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb >ffff88006c5f8e80: fc fc fc fc 00 00 00 00 00 00 00 07 fc fc fc fc ^ ffff88006c5f8f00: fb fb fb fb fb fb fb fb fc fc fc fc fb fb fb fb ffff88006c5f8f80: fb fb fb fb fc fc fc fc fc fc fc fc fc fc fc fc ==================================================================