On 12/15/20 12:07 AM, Willem de Bruijn wrote:
> On Mon, Dec 14, 2020 at 3:56 PM Jakub Kicinski wrote:
>>
>> On Sun, 13 Dec 2020 20:59:54 -0500 Willem de Bruijn wrote:
>>> On Sun, Dec 13, 2020 at 2:37 PM Vasily Averin wrote:
>> On 12/11/20 6:37 PM, Vasily Averin wrote:
>>> It seems for me
On Mon, Dec 14, 2020 at 3:56 PM Jakub Kicinski wrote:
>
> On Sun, 13 Dec 2020 20:59:54 -0500 Willem de Bruijn wrote:
> > On Sun, Dec 13, 2020 at 2:37 PM Vasily Averin wrote:
> > > >> On 12/11/20 6:37 PM, Vasily Averin wrote:
> > > >>> It seems for me the similar problem can happen in __skb_trim_r
On Sun, 13 Dec 2020 20:59:54 -0500 Willem de Bruijn wrote:
> On Sun, Dec 13, 2020 at 2:37 PM Vasily Averin wrote:
> > >> On 12/11/20 6:37 PM, Vasily Averin wrote:
> > >>> It seems for me the similar problem can happen in __skb_trim_rcsum().
> > >>> Also I doubt that that skb_checksum_start_offse
On Sun, Dec 13, 2020 at 2:37 PM Vasily Averin wrote:
>
> On 12/13/20 2:49 AM, Willem de Bruijn wrote:
> > On Sat, Dec 12, 2020 at 5:01 AM Vasily Averin wrote:
> >>
> >> On 12/11/20 6:37 PM, Vasily Averin wrote:
> >>> It seems for me the similar problem can happen in __skb_trim_rcsum().
> >>> Also
On 12/13/20 2:49 AM, Willem de Bruijn wrote:
> On Sat, Dec 12, 2020 at 5:01 AM Vasily Averin wrote:
>>
>> On 12/11/20 6:37 PM, Vasily Averin wrote:
>>> It seems for me the similar problem can happen in __skb_trim_rcsum().
>>> Also I doubt that that skb_checksum_start_offset(skb) checks in
>>> __sk
On Sat, Dec 12, 2020 at 5:01 AM Vasily Averin wrote:
>
> On 12/11/20 6:37 PM, Vasily Averin wrote:
> > It seems for me the similar problem can happen in __skb_trim_rcsum().
> > Also I doubt that that skb_checksum_start_offset(skb) checks in
> > __skb_postpull_rcsum() and skb_csum_unnecessary() are
On 12/11/20 6:37 PM, Vasily Averin wrote:
> It seems for me the similar problem can happen in __skb_trim_rcsum().
> Also I doubt that that skb_checksum_start_offset(skb) checks in
> __skb_postpull_rcsum() and skb_csum_unnecessary() are correct,
> becasue they do not guarantee that skb have correct
Originally it was reported on Ubuntu 4.14 kernel,
then I've reproduced it on upstream 5.10-rc7.
If I'm right the problem is quite old and should
affect all maintained stable kernels too.
It seems for me the similar problem can happen in __skb_trim_rcsum().
Also I doubt that that skb_checksum_star
syzkaller reproduces BUG_ON in skb_checksum_help():
tun creates skb with big partial checksum area and small ip packet inside,
then ip_rcv() decreases skb size of below length of checksummed area,
then checksum_tg() called via netfilter hook detects incorrect skb:
offset = skb_checksum_sta
