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To:     edumazet@google.com
Cc:     netdev@vger.kernel.org, eric.dumazet@gmail.com,
        syzkaller@googlegroups.com
Subject: Re: [PATCH net] slip: make slhc_compress() more robust against
 malicious packets
From:   David Miller <davem@davemloft.net>
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From: Eric Dumazet <edumazet@google.com>
Date: Wed,  4 Mar 2020 15:51:43 -0800

> Before accessing various fields in IPV4 network header
> and TCP header, make sure the packet :
> 
> - Has IP version 4 (ip->version == 4)
> - Has not a silly network length (ip->ihl >= 5)
> - Is big enough to hold network and transport headers
> - Has not a silly TCP header size (th->doff >= sizeof(struct tcphdr) / 4)
> 
> syzbot reported :
 ...
> Fixes: b5451d783ade ("slip: Move the SLIP drivers")
> Signed-off-by: Eric Dumazet <edumazet@google.com>
> Reported-by: syzbot <syzkaller@googlegroups.com>

Applied and queued up for -stable, thanks.