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From:   linke li <lilinke99@gmail.com>
Date:   Thu, 13 Jul 2023 15:57:00 +0800
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Subject: Re: [PATCH] hugetlbfs: Fix integer overflow check in hugetlbfs_file_mmap()
To:     Mike Kravetz <mike.kravetz@oracle.com>
Cc:     David Hildenbrand <david@redhat.com>,
        Linke Li <lilinke99@foxmail.com>, linux-mm@kvack.org,
        llvm@lists.linux.dev, linux-kernel@vger.kernel.org,
        trix@redhat.com, ndesaulniers@google.com, nathan@kernel.org,
        muchun.song@linux.dev
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> However, if this is a real issue it would make more
> sense to look for and change all such checks rather than one single occurrence.

Hi, Mike. I have checked the example code you provided, and the
difference between
those codes and the patched code is that those checks are checks for
unsigned integer
 overflow, which is well-defined. Only undefined behavior poses a
security risk. So they
 don't need any modifications. I have only found one occurrence of
signed number
overflow so far.

Thank you for your valuable feedback.