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MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org On Wed, 7 Aug 2019 12:59:00 -0400, Willem de Bruijn wrote: > On Wed, Aug 7, 2019 at 2:06 AM Jakub Kicinski wrote: > > diff --git a/net/core/sock.c b/net/core/sock.c > > index d57b0cc995a0..0f9619b0892f 100644 > > --- a/net/core/sock.c > > +++ b/net/core/sock.c > > @@ -1992,6 +1992,20 @@ void skb_set_owner_w(struct sk_buff *skb, struct sock *sk) > > } > > EXPORT_SYMBOL(skb_set_owner_w); > > > > +static bool can_skb_orphan_partial(const struct sk_buff *skb) > > +{ > > +#ifdef CONFIG_TLS_DEVICE > > + /* Drivers depend on in-order delivery for crypto offload, > > + * partial orphan breaks out-of-order-OK logic. > > + */ > > + if (skb->decrypted) > > + return false; > > +#endif > > + return (IS_ENABLED(CONFIG_INET) && > > + skb->destructor == tcp_wfree) || > > Please add parentheses around IS_ENABLED(CONFIG_INET) && > skb->destructor == tcp_wfree Mm.. there are parenthesis around them, maybe I'm being slow, could you show me how? > I was also surprised that this works when tcp_wfree is not defined if > !CONFIG_INET. But apparently it does (at -O2?) :) I was surprised to but in essence it should work the same as if (IS_ENABLED(CONFIG_xyz)) call_some_xyz_code(); from compiler's perspective, and we do that a lot. Perhaps kbuild bot will prove us wrong :) > > @@ -984,6 +984,9 @@ ssize_t do_tcp_sendpages(struct sock *sk, struct page *page, int offset, > > if (!skb) > > goto wait_for_memory; > > > > +#ifdef CONFIG_TLS_DEVICE > > + skb->decrypted = !!(flags & MSG_SENDPAGE_DECRYPTED); > > +#endif > > Nothing is stopping userspace from passing this new flag. In send > (tcp_sendmsg_locked) it is ignored. But can it reach do_tcp_sendpages > through tcp_bpf_sendmsg? Ah, I think you're right, thanks for checking that :( I don't entirely follow how 0608c69c9a80 ("bpf: sk_msg, sock{map|hash} redirect through ULP") is safe then. One option would be to clear the flags kernel would previously ignore in tcp_bpf_sendmsg(). But I feel like we should just go back to marking the socket, since we don't need the per-message flexibility of a flag. WDYT? > > skb_entail(sk, skb); > > copy = size_goal; > > } > > diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c > > index 6e4afc48d7bb..979520e46e33 100644 > > --- a/net/ipv4/tcp_output.c > > +++ b/net/ipv4/tcp_output.c > > @@ -1320,6 +1320,7 @@ int tcp_fragment(struct sock *sk, enum tcp_queue tcp_queue, > > buff = sk_stream_alloc_skb(sk, nsize, gfp, true); > > if (!buff) > > return -ENOMEM; /* We'll just try again later. */ > > + skb_copy_decrypted(buff, skb); > > This code has to copy timestamps, tx_flags, zerocopy state and now > this in three locations. Eventually we'll want a single helper for all > of them.. Ack, should I take an action on that for net-next or was it a note-to-self? :)