USB: f_mtp: Perform vfs_write under mutex protection

Use mutex protection to avoid request buffer freed while vfs_write or
copy_to_user happening if disconnect occurs.

Change-Id: Ie353b7495a8b7541f136d7e7ba3fc71db86987e8
Signed-off-by: Vijayavardhan Vennapusa <vvreddy@codeaurora.org>
Signed-off-by: Mayank Rana <mrana@codeaurora.org>
1 file changed