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34th chunk of `mount.man`
f2df54e2cb2fcee626324aca96cf55ecff1db3104a9b00200000000100000fa0
 lower
               Force the short name to lower case upon display; store a long
               name when the short name is not all upper case.

           win95
               Force the short name to upper case upon display; store a long
               name when the short name is not all upper case.

           winnt
               Display the short name as is; store a long name when the short
               name is not all lower case or all upper case.

           mixed
               Display the short name as is; store a long name when the short
               name is not all upper case. This mode is the default since Linux
               2.6.32.

   Mount options for usbfs
       devuid=uid and devgid=gid and devmode=mode
           Set the owner and group and mode of the device files in the usbfs
           filesystem (default: uid=gid=0, mode=0644). The mode is given in
           octal.

       busuid=uid and busgid=gid and busmode=mode
           Set the owner and group and mode of the bus directories in the usbfs
           filesystem (default: uid=gid=0, mode=0555). The mode is given in
           octal.

       listuid=uid and listgid=gid and listmode=mode
           Set the owner and group and mode of the file devices (default:
           uid=gid=0, mode=0444). The mode is given in octal.

DM-VERITY SUPPORT
       The device-mapper verity target provides read-only transparent integrity
       checking of block devices using kernel crypto API. The mount command can
       open the dm-verity device and do the integrity verification before the
       device filesystem is mounted. Requires libcryptsetup with in libmount
       (optionally via dlopen(3)). If libcryptsetup supports extracting the
       root hash of an already mounted device, existing devices will be
       automatically reused in case of a match. Mount options for dm-verity:

       verity.hashdevice=path
           Path to the hash tree device associated with the source volume to
           pass to dm-verity.

       verity.roothash=hex
           Hex-encoded hash of the root of verity.hashdevice. Mutually
           exclusive with verity.roothashfile.

       verity.roothashfile=path
           Path to file containing the hex-encoded hash of the root of
           verity.hashdevice. Mutually exclusive with verity.roothash.

       verity.hashoffset=offset
           If the hash tree device is embedded in the source volume, offset
           (default: 0) is used by dm-verity to get to the tree.

       verity.fecdevice=path
           Path to the Forward Error Correction (FEC) device associated with
           the source volume to pass to dm-verity. Optional. Requires kernel
           built with CONFIG_DM_VERITY_FEC.

       verity.fecoffset=offset
           If the FEC device is embedded in the source volume, offset (default:
           0) is used by dm-verity to get to the FEC area. Optional.

       verity.fecroots=value
           Parity bytes for FEC (default: 2). Optional.

       verity.roothashsig=path
           Path to pkcs7(1ssl) signature of root hash hex string. Requires
           crypt_activate_by_signed_key() from cryptsetup and kernel built with
           CONFIG_DM_VERITY_VERIFY_ROOTHASH_SIG. For device reuse, signatures
           have to be either used by all mounts of a device or by none.
           Optional.

       verity.oncorruption=ignore|restart|panic
           Instruct the kernel to ignore, reboot or panic when corruption is
           detected. By default the I/O operation simply fails. Requires Linux
           4.1 or newer, and libcrypsetup 2.3.4 or newer. Optional.

       Supported since util-linux v2.35.

       For example commands:

           mksquashfs /etc /tmp/etc.squashfs
           dd if=/dev/zero of=/tmp/etc.hash bs=1M count=10
           veritysetup format /tmp/etc.squashfs /tmp/etc.hash
           openssl smime -sign -in <hash> -nocerts -inkey private.key \
           -signer private.crt -noattr -binary
Title: USBFS Mount Options and DM-Verity Support
Summary
This section details the mount options for USBFS, focusing on setting the owner, group, and mode for device files and bus directories. It then discusses DM-Verity support, which provides read-only integrity checking of block devices. It covers options for specifying the hash device, root hash, hash offset, FEC device and offset, FEC roots, root hash signature, and the action to take upon corruption detection. The section concludes with example commands for using DM-Verity.