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Subject: Re: [PATCH] f2fs: add a condition to detect overflow in
 f2fs_ioc_gc_range()
To:     Sahitya Tummala <stummala@codeaurora.org>,
        Jaegeuk Kim <jaegeuk@kernel.org>,
        <linux-f2fs-devel@lists.sourceforge.net>
CC:     <linux-kernel@vger.kernel.org>
References: <1568695763-29343-1-git-send-email-stummala@codeaurora.org>
From:   Chao Yu <yuchao0@huawei.com>
Message-ID: <1ad336ce-a28a-9841-6438-2b0f851c0a6f@huawei.com>
Date:   Tue, 17 Sep 2019 14:18:22 +0800
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On 2019/9/17 12:49, Sahitya Tummala wrote:
> end = range.start + range.len;
> 
> If the range.start/range.len is a very large value, then end can overflow
> in this operation. It results into a crash in get_valid_blocks() when
> accessing the invalid range.start segno.
> 
> This issue is reported in ioctl fuzz testing.
> 
> Signed-off-by: Sahitya Tummala <stummala@codeaurora.org>

Reviewed-by: Chao Yu <yuchao0@huawei.com>

Thanks,