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Message-ID: <161736a2-1a79-b30a-002c-61ef9c237a22@kernel.org>
Date:   Tue, 23 May 2023 14:25:20 +0800
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Subject: Re: [PATCH v2] erofs: fix null-ptr-deref caused by
 erofs_xattr_prefixes_init
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To:     Jingbo Xu <jefflexu@linux.alibaba.com>, xiang@kernel.org,
        huyue2@coolpad.com, linux-erofs@lists.ozlabs.org
Cc:     linux-kernel@vger.kernel.org
References: <20230515103941.129784-1-jefflexu@linux.alibaba.com>
From:   Chao Yu <chao@kernel.org>
In-Reply-To: <20230515103941.129784-1-jefflexu@linux.alibaba.com>
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On 2023/5/15 18:39, Jingbo Xu wrote:
> Fragments and dedupe share one feature bit, and thus packed inode may not
> exist when fragment feature bit (dedupe feature bit exactly) is set, e.g.
> when deduplication feature is in use while fragments feature is not.  In
> this case, sbi->packed_inode could be NULL while fragments feature bit
> is set.
> 
> Fix this by accessing packed inode only when it exists.
> 
> Reported-by: syzbot+902d5a9373ae8f748a94@syzkaller.appspotmail.com
> Link: https://syzkaller.appspot.com/bug?extid=902d5a9373ae8f748a94
> Fixes: 9e382914617c ("erofs: add helpers to load long xattr name prefixes")
> Signed-off-by: Jingbo Xu <jefflexu@linux.alibaba.com>

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

Thanks,