MIPS: Compat: Use 32-bit wrapper for compat_sys_futex.
We can't trust userspace to pass signed-extend arguments. Not correctly
sign-extended arguments to futex-wait result in architecturally undefined
operation of 32-bit arithmetic instructions.
For example, if 'val' is too big and bit-31 is 1, the caller may enter
endless loop at:
futex_wait_setup()
{
...
if (uval != val) {
queue_unlock(q, *hb);
ret = -EWOULDBLOCK;
...
}
Signed-off-by: Yong Zhang <yong.zhang@windriver.com>
To: linux-mips@linux-mips.org
To: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/2714/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
3 files changed