Re: [LKP] [net] 34fad54c25: kernel BUG at include/linux/skbuff.h:1935!

From: Ye Xiaolong
Date: Wed Nov 23 2016 - 03:56:14 EST

On 11/22, Linus Torvalds wrote:
>On Tue, Nov 22, 2016 at 10:44 PM, Fengguang Wu <fengguang.wu@xxxxxxxxx> wrote:
>> On Tue, Nov 22, 2016 at 02:04:42PM -0800, Linus Torvalds wrote:
>>> I also noticed that the kernel test robot had screwed up the
>>> participants list for some reason, and had
>>> "Acked-by: Alexander Duyck <alexander.h.duyck@xxxxxxxxx>, David S.
>>> Miller" <davem@xxxxxxxxxxxxx>
>>> as one of the participants. So there's some odd commit parsing issue
>>> there somewhere. But Alexander seems to have seen this report despite
>>> that, it just never went anywhere that I can tell.
>> Yeah the robot will CC all "Acked-by" people in the bug reports.
>> Shall we limit it to the below TO/CC list?
>No. We do want to keep the Acked-by's on the cc.
>But you missed the real problem.
>It *didn't* cc the acked-by. Look closer. What happened was that it cc'd this:
> "Acked-by: Alexander Duyck <alexander.h.duyck@xxxxxxxxx>, David S. Miller"
> <davem@xxxxxxxxxxxxx>

Seems that the robot failed to parse the commit log correctly due to
the "Reported-by: xxx" line missed '>' in the end, the robot got fooled
by it and generated wrong result, we'll try to improve it to handle this
kind of case.

net: __skb_flow_dissect() must cap its return value

After Tom patch, thoff field could point past the end of the buffer,
this could fool some callers.

If an skb was provided, skb->len should be the upper limit.
If not, hlen is supposed to be the upper limit.

Fixes: a6e544b0a88b ("flow_dissector: Jump to exit code in __skb_flow_dissect")
Signed-off-by: Eric Dumazet <edumazet@xxxxxxxxxx>
Reported-by: Yibin Yang <yibyang@xxxxxxxxx
Acked-by: Alexander Duyck <alexander.h.duyck@xxxxxxxxx>
Acked-by: Willem de Bruijn <willemb@xxxxxxxxxx>
Acked-by: Alexei Starovoitov <ast@xxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>


>ie there is only _one_ email address (that of davem@xxxxxxxxxxxxx),
>and the whole "Acked-by: Alexander Duyck <...>" part is quoted as the
>_name_ of that email address.
>At least that's what the headers look like for me in the original report:
> From: kernel test robot <>
> To: Eric Dumazet <edumazet@xxxxxxxxxx>
> Cc: lkp@xxxxxx, Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>,
>LKML <linux-kernel@xxxxxxxxxxxxxxx>, Alexei Starovoitov
><ast@xxxxxxxxxx>, Willem de Bruijn <willemb@xxxxxxxxxx>, "Acked-by:
>Alexander Duyck <alexander.h.duyck@xxxxxxxxx>, David S. Miller"
>Notice the quoting of that last "name".
> Linus