From: Cong Wang <xiyou.wangcong@gmail.com>
To: Eric Dumazet <eric.dumazet@gmail.com>
Cc: syzbot <syzbot+5af9a90dad568aa9f611@syzkaller.appspotmail.com>,
David Miller <davem@davemloft.net>,
Jamal Hadi Salim <jhs@mojatatu.com>,
Jiri Pirko <jiri@resnulli.us>,
LKML <linux-kernel@vger.kernel.org>,
Linux Kernel Network Developers <netdev@vger.kernel.org>,
syzkaller-bugs <syzkaller-bugs@googlegroups.com>
Subject: Re: KASAN: slab-out-of-bounds Read in __nla_put_nohdr
Date: Wed, 22 Jan 2020 12:27:11 -0800 [thread overview]
Message-ID: <CAM_iQpXqh1ucVST199c72V22zLPujZy-54p=c5ar=Q9bWNq7OA@mail.gmail.com> (raw)
In-Reply-To: <50239085-ff0f-f797-99af-1a0e58bc5e2e@gmail.com>
On Tue, Jan 21, 2020 at 11:55 AM Eric Dumazet <eric.dumazet@gmail.com> wrote:
> em_nbyte_change() sets
> em->datalen = sizeof(*nbyte) + nbyte->len;
>
> But later tcf_em_validate() overwrites em->datalen with the user provide value (em->datalen = data_len; )
> which can be bigger than the allocated (kmemdup) space in em_nbyte_change()
>
> Should net/sched/em_nbyte.c() provide a dump() handler to avoid this issue ?
I think for those who implement ->change() we should leave
->datalen untouched to respect their choices. I don't see why
we have to set it twice.
Thanks.
next prev parent reply other threads:[~2020-01-22 20:27 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-01-21 19:47 KASAN: slab-out-of-bounds Read in __nla_put_nohdr syzbot
2020-01-21 19:55 ` Eric Dumazet
2020-01-22 20:27 ` Cong Wang [this message]
2020-01-22 20:33 ` Eric Dumazet
2020-01-22 22:09 ` Cong Wang
2020-01-23 7:13 ` Dan Carpenter
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