metag/usercopy: Add early abort to copy_to_user
authorJames Hogan <james.hogan@imgtec.com>
Fri, 31 Mar 2017 12:35:01 +0000 (13:35 +0100)
committerJames Hogan <james.hogan@imgtec.com>
Wed, 5 Apr 2017 13:49:42 +0000 (14:49 +0100)
commitfb8ea062a8f2e85256e13f55696c5c5f0dfdcc8b
tree263488d227fe8bb0dea7749a07d45de104c62bd9
parent2257211942bbbf6c798ab70b487d7e62f7835a1a
metag/usercopy: Add early abort to copy_to_user

When copying to userland on Meta, if any faults are encountered
immediately abort the copy instead of continuing on and repeatedly
faulting, and worse potentially copying further bytes successfully to
subsequent valid pages.

Fixes: 373cd784d0fc ("metag: Memory handling")
Reported-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: linux-metag@vger.kernel.org
Cc: stable@vger.kernel.org
arch/metag/lib/usercopy.c