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Date:   Fri, 10 Jul 2020 13:12:32 +0200
From:   Dominique Martinet <asmadeus@codewreck.org>
To:     Christoph Hellwig <hch@lst.de>
Cc:     ericvh@gmail.com, lucho@ionkov.net,
        v9fs-developer@lists.sourceforge.net, netdev@vger.kernel.org,
        linux-kernel@vger.kernel.org,
        syzbot+e6f77e16ff68b2434a2c@syzkaller.appspotmail.com
Subject: Re: [PATCH] net/9p: validate fds in p9_fd_open
Message-ID: <20200710111232.GC17924@nautica>
References: <20200710085722.435850-1-hch@lst.de>
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Christoph Hellwig wrote on Fri, Jul 10, 2020:
> p9_fd_open just fgets file descriptors passed in from userspace, but
> doesn't verify that they are valid for read or writing.  This gets
> cought down in the VFS when actually attemping a read or write, but a
> new warning added in linux-next upsets syzcaller.
> 
> Fix this by just verifying the fds early on.
> 
> Reported-by: syzbot+e6f77e16ff68b2434a2c@syzkaller.appspotmail.com
> Signed-off-by: Christoph Hellwig <hch@lst.de>

Looks good to me, I'll pick it up shortly.

-- 
Dominique