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Date:   Tue, 16 Jul 2019 14:57:16 -0400
From:   Steven Rostedt <rostedt@goodmis.org>
To:     Nick Desaulniers <ndesaulniers@google.com>
Cc:     Jeffrin Thalakkottoor <jeffrin@rajagiritech.edu.in>,
        Andy Shevchenko <andriy.shevchenko@linux.intel.com>,
        Alexander Shishkin <alexander.shishkin@linux.intel.com>,
        tobin@kernel.org, lkml <linux-kernel@vger.kernel.org>,
        Kees Cook <keescook@chromium.org>,
        Dmitry Vyukov <dvyukov@google.com>,
        Alexander Potapenko <glider@google.com>
Subject: Re: BUG: KASAN: global-out-of-bounds in
 ata_exec_internal_sg+0x50f/0xc70
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On Tue, 16 Jul 2019 11:28:29 -0700
Nick Desaulniers <ndesaulniers@google.com> wrote:

> The cited code looks like a check comparing that the pointer distance
> is greater than the size of bytes being passed in.  I'd wager
> someone's calling memmove with overlapping memory regions when they
> really wanted memcpy.  Maybe a better question, is why was memmove
> ever used; if there was some invariant that the memory regions
> overlapped, why is that invariant no longer holding.

I'm confused by the above statement as memmove() allows overlapping of
src and dest, where as memcpy() does not.

-- Steve