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Message-ID: <3f0b9ff1-eea5-150c-c57e-4e1d0a06e220@kernel.org>
Date:   Tue, 6 Dec 2022 23:09:15 +0800
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Subject: Re: [PATCH 2/2] erofs: validate the extent length for uncompressed
 pclusters
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To:     Gao Xiang <hsiangkao@linux.alibaba.com>,
        linux-erofs@lists.ozlabs.org
Cc:     LKML <linux-kernel@vger.kernel.org>,
        syzbot+2ae90e873e97f1faf6f2@syzkaller.appspotmail.com
References: <20221205150050.47784-1-hsiangkao@linux.alibaba.com>
 <20221205150050.47784-2-hsiangkao@linux.alibaba.com>
From:   Chao Yu <chao@kernel.org>
In-Reply-To: <20221205150050.47784-2-hsiangkao@linux.alibaba.com>
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On 2022/12/5 23:00, Gao Xiang wrote:
> syzkaller reported a KASAN use-after-free:
> https://syzkaller.appspot.com/bug?extid=2ae90e873e97f1faf6f2
> 
> The referenced fuzzed image actually has two issues:
>   - m_pa == 0 as a non-inlined pcluster;
>   - The logical length is longer than its physical length.
> 
> The first issue has already been addressed.  This patch addresses
> the second issue by checking the extent length validity.
> 
> Reported-by: syzbot+2ae90e873e97f1faf6f2@syzkaller.appspotmail.com
> Fixes: 02827e1796b3 ("staging: erofs: add erofs_map_blocks_iter")
> Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>

Reviewed-by: Chao Yu <chao@kernel.org>

Thanks,