Re: [PATCH net-next 0/4] net: skb: check the boundrary of skb drop reason

[Menglong Dong]

On Thu, May 12, 2022 at 2:26 PM <menglong8.dong@xxxxxxxxx> wrote:
>
> From: Menglong Dong <imagedong@xxxxxxxxxxx>
>
> In the commit 1330b6ef3313 ("skb: make drop reason booleanable"),
> SKB_NOT_DROPPED_YET is added to the enum skb_drop_reason, which makes
> the invalid drop reason SKB_NOT_DROPPED_YET can leak to the kfree_skb
> tracepoint. Once this happen (it happened, as 4th patch says), it can
> cause NULL pointer in drop monitor and result in kernel panic.
>
> Therefore, check the boundrary of drop reason in both kfree_skb_reason
> (2th patch) and drop monitor (1th patch).
>
> Meanwhile, fix the invalid drop reason passed to kfree_skb_reason() in
> tcp_v4_rcv().
>

tcp_v6_rcv() is forgeted, I'll send a V2 :/

> Menglong Dong (4):
>   net: dm: check the boundary of skb drop reasons
>   net: skb: check the boundrary of drop reason in kfree_skb_reason()
>   net: skb: change the definition SKB_DR_SET()
>   net: tcp: reset skb drop reason to NOT_SPCIFIED in tcp_v4_rcv()
>
>  include/linux/skbuff.h  | 3 ++-
>  net/core/drop_monitor.c | 2 +-
>  net/core/skbuff.c       | 5 +++++
>  net/ipv4/tcp_ipv4.c     | 1 +
>  4 files changed, 9 insertions(+), 2 deletions(-)
>
> --
> 2.36.1
>