On Thu, Jul 01, 2021 at 08:16 AM CEST, Cong Wang wrote:
> From: Cong Wang <cong.wang@xxxxxxxxxxxxx>
>
> Jiang observed OOM frequently when testing our AF_UNIX/UDP
> proxy. This is due to the fact that we do not actually limit
> the socket memory before queueing skb to ingress_skb. We
> charge the skb memory later when handling the psock backlog,
> but it is not limited either.
>
> This patch adds checks for sk->sk_rcvbuf right before queuing
> to ingress_skb and drops packets if this limit exceeds. This
> is very similar to UDP receive path. Ideally we should set the
> skb owner before this check too, but it is hard to make TCP
> happy about sk_forward_alloc.
>
> Reported-by: Jiang Wang <jiang.wang@xxxxxxxxxxxxx>
> Cc: Daniel Borkmann <daniel@xxxxxxxxxxxxx>
> Cc: John Fastabend <john.fastabend@xxxxxxxxx>
> Cc: Lorenz Bauer <lmb@xxxxxxxxxxxxxx>
> Cc: Jakub Sitnicki <jakub@xxxxxxxxxxxxxx>
> Signed-off-by: Cong Wang <cong.wang@xxxxxxxxxxxxx>
> ---
Acked-by: Jakub Sitnicki <jakub@xxxxxxxxxxxxxx>
By saying that it is hard to make TCP happy about sk_forward_alloc, I'm
guessing you're referring to problems described in 144748eb0c44 ("bpf,
sockmap: Fix incorrect fwd_alloc accounting") [1]?
Thanks for the fix.
[1] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=144748eb0c445091466c9b741ebd0bfcc5914f3d
[...]
