diff mbox series

[net-next,v4,4/5] tcp: directly drop skb in cookie check for ipv6

Message ID 20240213134205.8705-5-kerneljasonxing@gmail.com (mailing list archive)
State Changes Requested
Delegated to: Netdev Maintainers
Headers show
Series introduce drop reasons for cookie check | expand

Checks

Context Check Description
netdev/series_format success Posting correctly formatted
netdev/tree_selection success Clearly marked for net-next
netdev/ynl success Generated files up to date; no warnings/errors; no diff in generated;
netdev/fixes_present success Fixes tag not required for -next series
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 991 this patch: 991
netdev/build_tools success No tools touched, skip
netdev/cc_maintainers success CCed 5 of 5 maintainers
netdev/build_clang success Errors and warnings before: 1006 this patch: 1006
netdev/verify_signedoff success Signed-off-by tag matches author and committer
netdev/deprecated_api success None detected
netdev/check_selftest success No net selftest shell script
netdev/verify_fixes success No Fixes tag
netdev/build_allmodconfig_warn success Errors and warnings before: 1008 this patch: 1008
netdev/checkpatch success total: 0 errors, 0 warnings, 0 checks, 33 lines checked
netdev/build_clang_rust success No Rust files in patch. Skipping build
netdev/kdoc success Errors and warnings before: 0 this patch: 0
netdev/source_inline success Was 0 now: 0
netdev/contest success net-next-2024-02-13--21-00 (tests: 1437)

Commit Message

Jason Xing Feb. 13, 2024, 1:42 p.m. UTC 
From: Jason Xing <kernelxing@tencent.com>

Like previous patch does, only moving skb drop logical code to
cookie_v6_check() for later refinement.

Signed-off-by: Jason Xing <kernelxing@tencent.com>
---
 net/ipv6/syncookies.c | 4 ++++
 net/ipv6/tcp_ipv6.c   | 7 +++++--
 2 files changed, 9 insertions(+), 2 deletions(-)

Comments

Eric Dumazet Feb. 13, 2024, 3:30 p.m. UTC | #1 
On Tue, Feb 13, 2024 at 2:42 PM Jason Xing <kerneljasonxing@gmail.com> wrote:
>
> From: Jason Xing <kernelxing@tencent.com>
>
> Like previous patch does, only moving skb drop logical code to
> cookie_v6_check() for later refinement.
>
> Signed-off-by: Jason Xing <kernelxing@tencent.com>
> ---
>  net/ipv6/syncookies.c | 4 ++++
>  net/ipv6/tcp_ipv6.c   | 7 +++++--
>  2 files changed, 9 insertions(+), 2 deletions(-)
>
> diff --git a/net/ipv6/syncookies.c b/net/ipv6/syncookies.c
> index 6b9c69278819..ea0d9954a29f 100644
> --- a/net/ipv6/syncookies.c
> +++ b/net/ipv6/syncookies.c
> @@ -177,6 +177,7 @@ struct sock *cookie_v6_check(struct sock *sk, struct sk_buff *skb)
>         struct sock *ret = sk;
>         __u8 rcv_wscale;
>         int full_space;
> +       SKB_DR(reason);
>
>         if (!READ_ONCE(net->ipv4.sysctl_tcp_syncookies) ||
>             !th->ack || th->rst)
> @@ -256,10 +257,13 @@ struct sock *cookie_v6_check(struct sock *sk, struct sk_buff *skb)
>         ireq->ecn_ok &= cookie_ecn_ok(net, dst);
>
>         ret = tcp_get_cookie_sock(sk, skb, req, dst);
> +       if (!ret)
> +               goto out_drop;
>  out:
>         return ret;
>  out_free:
>         reqsk_free(req);
>  out_drop:
> +       kfree_skb_reason(skb, reason);
>         return NULL;
>  }
> diff --git a/net/ipv6/tcp_ipv6.c b/net/ipv6/tcp_ipv6.c
> index 57b25b1fc9d9..27639ffcae2f 100644
> --- a/net/ipv6/tcp_ipv6.c
> +++ b/net/ipv6/tcp_ipv6.c
> @@ -1653,8 +1653,11 @@ int tcp_v6_do_rcv(struct sock *sk, struct sk_buff *skb)
>         if (sk->sk_state == TCP_LISTEN) {
>                 struct sock *nsk = tcp_v6_cookie_check(sk, skb);
>
> -               if (!nsk)
> -                       goto discard;
> +               if (!nsk) {
> +                       if (opt_skb)
> +                               __kfree_skb(opt_skb);
> +                       return 0;
> +               }
>
>                 if (nsk != sk) {
>                         if (tcp_child_process(sk, nsk, skb))
> --

or perhaps try to avoid duplication of these opt_skb tests/actions.

diff --git a/net/ipv6/tcp_ipv6.c b/net/ipv6/tcp_ipv6.c
index 57b25b1fc9d9d529e3c53778ef09b65b1ac4c9d5..1ca4f11c3d6f3af2a0148f0e50dfea96b8ba3a53
100644
--- a/net/ipv6/tcp_ipv6.c
+++ b/net/ipv6/tcp_ipv6.c
@@ -1653,16 +1653,13 @@ int tcp_v6_do_rcv(struct sock *sk, struct sk_buff *skb)
        if (sk->sk_state == TCP_LISTEN) {
                struct sock *nsk = tcp_v6_cookie_check(sk, skb);

-               if (!nsk)
-                       goto discard;
-
-               if (nsk != sk) {
+               if (nsk && nsk != sk) {
                        if (tcp_child_process(sk, nsk, skb))
                                goto reset;
-                       if (opt_skb)
-                               __kfree_skb(opt_skb);
-                       return 0;
                }
+               if (opt_skb)
+                       __kfree_skb(opt_skb);
+               return 0;
        } else
                sock_rps_save_rxhash(sk, skb);
Jason Xing Feb. 13, 2024, 5:09 p.m. UTC | #2 
On Tue, Feb 13, 2024 at 11:30 PM Eric Dumazet <edumazet@google.com> wrote:
>
> On Tue, Feb 13, 2024 at 2:42 PM Jason Xing <kerneljasonxing@gmail.com> wrote:
> >
> > From: Jason Xing <kernelxing@tencent.com>
> >
> > Like previous patch does, only moving skb drop logical code to
> > cookie_v6_check() for later refinement.
> >
> > Signed-off-by: Jason Xing <kernelxing@tencent.com>
> > ---
> >  net/ipv6/syncookies.c | 4 ++++
> >  net/ipv6/tcp_ipv6.c   | 7 +++++--
> >  2 files changed, 9 insertions(+), 2 deletions(-)
> >
> > diff --git a/net/ipv6/syncookies.c b/net/ipv6/syncookies.c
> > index 6b9c69278819..ea0d9954a29f 100644
> > --- a/net/ipv6/syncookies.c
> > +++ b/net/ipv6/syncookies.c
> > @@ -177,6 +177,7 @@ struct sock *cookie_v6_check(struct sock *sk, struct sk_buff *skb)
> >         struct sock *ret = sk;
> >         __u8 rcv_wscale;
> >         int full_space;
> > +       SKB_DR(reason);
> >
> >         if (!READ_ONCE(net->ipv4.sysctl_tcp_syncookies) ||
> >             !th->ack || th->rst)
> > @@ -256,10 +257,13 @@ struct sock *cookie_v6_check(struct sock *sk, struct sk_buff *skb)
> >         ireq->ecn_ok &= cookie_ecn_ok(net, dst);
> >
> >         ret = tcp_get_cookie_sock(sk, skb, req, dst);
> > +       if (!ret)
> > +               goto out_drop;
> >  out:
> >         return ret;
> >  out_free:
> >         reqsk_free(req);
> >  out_drop:
> > +       kfree_skb_reason(skb, reason);
> >         return NULL;
> >  }
> > diff --git a/net/ipv6/tcp_ipv6.c b/net/ipv6/tcp_ipv6.c
> > index 57b25b1fc9d9..27639ffcae2f 100644
> > --- a/net/ipv6/tcp_ipv6.c
> > +++ b/net/ipv6/tcp_ipv6.c
> > @@ -1653,8 +1653,11 @@ int tcp_v6_do_rcv(struct sock *sk, struct sk_buff *skb)
> >         if (sk->sk_state == TCP_LISTEN) {
> >                 struct sock *nsk = tcp_v6_cookie_check(sk, skb);
> >
> > -               if (!nsk)
> > -                       goto discard;
> > +               if (!nsk) {
> > +                       if (opt_skb)
> > +                               __kfree_skb(opt_skb);
> > +                       return 0;
> > +               }
> >
> >                 if (nsk != sk) {
> >                         if (tcp_child_process(sk, nsk, skb))
> > --
>
> or perhaps try to avoid duplication of these opt_skb tests/actions.
>
> diff --git a/net/ipv6/tcp_ipv6.c b/net/ipv6/tcp_ipv6.c
> index 57b25b1fc9d9d529e3c53778ef09b65b1ac4c9d5..1ca4f11c3d6f3af2a0148f0e50dfea96b8ba3a53
> 100644
> --- a/net/ipv6/tcp_ipv6.c
> +++ b/net/ipv6/tcp_ipv6.c
> @@ -1653,16 +1653,13 @@ int tcp_v6_do_rcv(struct sock *sk, struct sk_buff *skb)
>         if (sk->sk_state == TCP_LISTEN) {
>                 struct sock *nsk = tcp_v6_cookie_check(sk, skb);
>
> -               if (!nsk)
> -                       goto discard;
> -
> -               if (nsk != sk) {
> +               if (nsk && nsk != sk) {
>                         if (tcp_child_process(sk, nsk, skb))
>                                 goto reset;
> -                       if (opt_skb)
> -                               __kfree_skb(opt_skb);
> -                       return 0;
>                 }
> +               if (opt_skb)
> +                       __kfree_skb(opt_skb);
> +               return 0;
>         } else
>                 sock_rps_save_rxhash(sk, skb);

Thanks for your advice. Will update it:)

Thanks,
Jason
diff mbox series

Patch

diff --git a/net/ipv6/syncookies.c b/net/ipv6/syncookies.c
index 6b9c69278819..ea0d9954a29f 100644
--- a/net/ipv6/syncookies.c
+++ b/net/ipv6/syncookies.c
@@ -177,6 +177,7 @@  struct sock *cookie_v6_check(struct sock *sk, struct sk_buff *skb)
 	struct sock *ret = sk;
 	__u8 rcv_wscale;
 	int full_space;
+	SKB_DR(reason);
 
 	if (!READ_ONCE(net->ipv4.sysctl_tcp_syncookies) ||
 	    !th->ack || th->rst)
@@ -256,10 +257,13 @@  struct sock *cookie_v6_check(struct sock *sk, struct sk_buff *skb)
 	ireq->ecn_ok &= cookie_ecn_ok(net, dst);
 
 	ret = tcp_get_cookie_sock(sk, skb, req, dst);
+	if (!ret)
+		goto out_drop;
 out:
 	return ret;
 out_free:
 	reqsk_free(req);
 out_drop:
+	kfree_skb_reason(skb, reason);
 	return NULL;
 }
diff --git a/net/ipv6/tcp_ipv6.c b/net/ipv6/tcp_ipv6.c
index 57b25b1fc9d9..27639ffcae2f 100644
--- a/net/ipv6/tcp_ipv6.c
+++ b/net/ipv6/tcp_ipv6.c
@@ -1653,8 +1653,11 @@  int tcp_v6_do_rcv(struct sock *sk, struct sk_buff *skb)
 	if (sk->sk_state == TCP_LISTEN) {
 		struct sock *nsk = tcp_v6_cookie_check(sk, skb);
 
-		if (!nsk)
-			goto discard;
+		if (!nsk) {
+			if (opt_skb)
+				__kfree_skb(opt_skb);
+			return 0;
+		}
 
 		if (nsk != sk) {
 			if (tcp_child_process(sk, nsk, skb))