1. 05 Sep, 2019 1 commit
  2. 04 Sep, 2019 2 commits
    • Alan Stern's avatar
      USB: usbcore: Fix slab-out-of-bounds bug during device reset · 3dd550a2
      Alan Stern authored
      The syzbot fuzzer provoked a slab-out-of-bounds error in the USB core:
      
      BUG: KASAN: slab-out-of-bounds in memcmp+0xa6/0xb0 lib/string.c:904
      Read of size 1 at addr ffff8881d175bed6 by task kworker/0:3/2746
      
      CPU: 0 PID: 2746 Comm: kworker/0:3 Not tainted 5.3.0-rc5+ #28
      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]
        descriptors_changed drivers/usb/core/hub.c:5579 [inline]
        usb_reset_and_verify_device+0x564/0x1300 drivers/usb/core/hub.c:5729
        usb_reset_device+0x4c1/0x920 drivers/usb/core/hub.c:5898
        rt2x00usb_probe+0x53/0x7af
      drivers/net/wireless/ralink/rt2x00/rt2x00usb.c:806
      
      The error occurs when the descriptors_changed() routine (called during
      a device reset) attempts to compare the old and new BOS and capability
      descriptors.  The length it uses for the comparison is the
      wTotalLength value stored in BOS descriptor, but this value is not
      necessarily the same as the length actually allocated for the
      descriptors.  If it is larger the routine will call memcmp() with a
      length that is too big, thus reading beyond the end of the allocated
      region and leading to this fault.
      
      The kernel reads the BOS descriptor twice: first to get the total
      length of all the capability descriptors, and second to read it along
      with all those other descriptors.  A malicious (or very faulty) device
      may send different values for the BOS descriptor fields each time.
      The memory area will be allocated using the wTotalLength value read
      the first time, but stored within it will be the value read the second
      time.
      
      To prevent this possibility from causing any errors, this patch
      modifies the BOS descriptor after it has been read the second time:
      It sets the wTotalLength field to the actual length of the descriptors
      that were read in and validated.  Then the memcpy() call, or any other
      code using these descriptors, will be able to rely on wTotalLength
      being valid.
      
      Reported-and-tested-by: syzbot+35f4d916c623118d576e@syzkaller.appspotmail.com
      Signed-off-by: default avatarAlan Stern <stern@rowland.harvard.edu>
      CC: <stable@vger.kernel.org>
      Link: https://lore.kernel.org/r/Pine.LNX.4.44L0.1909041154260.1722-100000@iolanthe.rowland.orgSigned-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      3dd550a2
    • Greg Kroah-Hartman's avatar
      Merge tag 'usb-serial-5.4-rc1' of... · 11c302f2
      Greg Kroah-Hartman authored
      Merge tag 'usb-serial-5.4-rc1' of https://git.kernel.org/pub/scm/linux/kernel/git/johan/usb-serial into usb-next
      
      Johan writes:
      
      USB-serial updates for 5.4-rc1
      
      Here are the USB-serial updates for 5.4-rc1, which this time is just a
      single commit adding support for the CBUS GPIOs on FT232H devices.
      
      This change has spent a week in linux-next with no reported issues.
      Signed-off-by: default avatarJohan Hovold <johan@kernel.org>
      
      * tag 'usb-serial-5.4-rc1' of https://git.kernel.org/pub/scm/linux/kernel/git/johan/usb-serial:
        USB: serial: ftdi_sio: add support for FT232H CBUS gpios
      11c302f2
  3. 03 Sep, 2019 37 commits