lkml.org 
[lkml]   [2019]   [Aug]   [12]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
From
Date
SubjectRe: KASAN: slab-out-of-bounds Read in usbnet_generic_cdc_bind
On Mon, Aug 12, 2019 at 2:18 PM syzbot
<syzbot+45a53506b65321c1fe91@syzkaller.appspotmail.com> wrote:
>
> 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=1390791c600000
> kernel config: https://syzkaller.appspot.com/x/.config?x=cfa2c18fb6a8068e
> dashboard link: https://syzkaller.appspot.com/bug?extid=45a53506b65321c1fe91
> compiler: gcc (GCC) 9.0.0 20181231 (experimental)
> syz repro: https://syzkaller.appspot.com/x/repro.syz?x=12c78cd2600000
> C reproducer: https://syzkaller.appspot.com/x/repro.c?x=1395b40e600000
>
> IMPORTANT: if you fix the bug, please add the following tag to the commit:
> Reported-by: syzbot+45a53506b65321c1fe91@syzkaller.appspotmail.com
>
> usb 1-1: config 1 interface 0 altsetting 0 has 0 endpoint descriptors,
> different from the interface descriptor's value: 18
> usb 1-1: New USB device found, idVendor=0525, idProduct=a4a1, bcdDevice=
> 0.40
> usb 1-1: New USB device strings: Mfr=6, Product=0, SerialNumber=0
> ==================================================================
> BUG: KASAN: slab-out-of-bounds in memcmp+0xa6/0xb0 lib/string.c:904
> Read of size 1 at addr ffff8881d4262f3b by task kworker/1:2/83
>
> CPU: 1 PID: 83 Comm: kworker/1:2 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
> memcmp+0xa6/0xb0 lib/string.c:904
> memcmp include/linux/string.h:400 [inline]
> usbnet_generic_cdc_bind+0x71b/0x17c0 drivers/net/usb/cdc_ether.c:225
> usbnet_ether_cdc_bind drivers/net/usb/cdc_ether.c:322 [inline]
> usbnet_cdc_bind+0x20/0x1a0 drivers/net/usb/cdc_ether.c:430
> usbnet_probe+0xb43/0x23d0 drivers/net/usb/usbnet.c:1722
> 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
>
> Allocated by task 83:
> 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]
> usb_get_configuration+0x30c/0x3070 drivers/usb/core/config.c:857
> usb_enumerate_device drivers/usb/core/hub.c:2369 [inline]
> usb_new_device+0xd3/0x160 drivers/usb/core/hub.c:2505
> 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 269:
> 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
> kobject_uevent_env+0x294/0x1160 lib/kobject_uevent.c:624
> kobject_synth_uevent+0x70a/0x81e lib/kobject_uevent.c:208
> uevent_store+0x20/0x50 drivers/base/core.c:1244
> dev_attr_store+0x50/0x80 drivers/base/core.c:947
> sysfs_kf_write+0x110/0x160 fs/sysfs/file.c:138
> kernfs_fop_write+0x2b0/0x470 fs/kernfs/file.c:315
> __vfs_write+0x76/0x100 fs/read_write.c:494
> vfs_write+0x262/0x5c0 fs/read_write.c:558
> ksys_write+0x127/0x250 fs/read_write.c:611
> do_syscall_64+0xb7/0x580 arch/x86/entry/common.c:296
> entry_SYSCALL_64_after_hwframe+0x49/0xbe
>
> The buggy address belongs to the object at ffff8881d4262f00
> which belongs to the cache kmalloc-64 of size 64
> The buggy address is located 59 bytes inside of
> 64-byte region [ffff8881d4262f00, ffff8881d4262f40)
> The buggy address belongs to the page:
> page:ffffea0007509880 refcount:1 mapcount:0 mapping:ffff8881da003180
> index:0x0
> flags: 0x200000000000200(slab)
> raw: 0200000000000200 ffffea00074d1f00 0000001800000018 ffff8881da003180
> raw: 0000000000000000 00000000802a002a 00000001ffffffff 0000000000000000
> page dumped because: kasan: bad access detected
>
> Memory state around the buggy address:
> ffff8881d4262e00: fb fb fb fb fc fc fc fc 00 00 00 00 00 00 fc fc
> ffff8881d4262e80: fc fc fc fc fb fb fb fb fb fb fb fb fc fc fc fc
> > ffff8881d4262f00: 00 00 00 00 00 00 00 03 fc fc fc fc fb fb fb fb
> ^
> ffff8881d4262f80: fb fb fb fb fc fc fc fc fc fc fc fc fc fc fc fc
> ffff8881d4263000: fb fb fb fb fb fb fb fb fb fb fc fc fc fc fb fb
> ==================================================================

This one is funny, we do sizeof(struct usb_cdc_mdlm_desc *) instead of
sizeof(struct usb_cdc_mdlm_desc) and the same for
usb_cdc_mdlm_detail_desc in cdc_parse_cdc_header().

>
>
> ---
> 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
>
> --
> You received this message because you are subscribed to the Google Groups "syzkaller-bugs" group.
> To unsubscribe from this group and stop receiving emails from it, send an email to syzkaller-bugs+unsubscribe@googlegroups.com.
> To view this discussion on the web visit https://groups.google.com/d/msgid/syzkaller-bugs/000000000000487b44058fea845c%40google.com.

\
 
 \ /
  Last update: 2019-08-12 14:28    [W:0.071 / U:0.028 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site