Re: [PATCH v3 2/4] x86, mpx: hook #BR exception handler to allocatebound tables

From: Ren Qiaowei
Date: Tue Jan 28 2014 - 01:53:19 EST


On 01/28/2014 02:42 PM, Andy Lutomirski wrote:
I just read it. do_trap_no_signal presumably calls fixup_exception
because #UD uses it and #UD needs that handling. (I'm guessing that
there is actually a legitimate use for a kernel fixup on #UD somewhere
-- there's probably something that isn't covered by cpuid.)

There should not be a #BR from the kernel using the fixup mechanism.
IMO if the exception comes from the kernel, it should unconditionally
call die.

Oh. I agree with you, and if a #BR from the kernel it should unconditionally call die.

if (!user_mode(regs))
die("bounds", regs, error_code);

Thanks,
Qiaowei
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/