If user get root access and calls security.selinux setxattr() with an
embedded NUL on a file and then if some process performs a getxattr()
on that file with a length greater than the actual length of the string,
it would result in a panic.
To fix this, add the actual length of the string to the security context
instead of the length passed by the userspace process.
Signed-off-by: Sachin Grover <sgrover@codeaurora.org> Cc: stable@vger.kernel.org Signed-off-by: Paul Moore <paul@paul-moore.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>