diff mbox series

[net-next,v4,3/5] tcp: use drop reasons in cookie check for ipv4

Message ID 20240213134205.8705-4-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: 992 this patch: 992
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: 1007 this patch: 1007
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: 1009 this patch: 1009
netdev/checkpatch success total: 0 errors, 0 warnings, 0 checks, 47 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>

Now it's time to use the prepared definitions to refine this part.
Four reasons used might enough for now, I think.

Signed-off-by: Jason Xing <kernelxing@tencent.com>
---
 net/ipv4/syncookies.c | 18 +++++++++++++-----
 1 file changed, 13 insertions(+), 5 deletions(-)

Comments

David Ahern Feb. 13, 2024, 3:56 p.m. UTC | #1 
On 2/13/24 6:42 AM, Jason Xing wrote:
> diff --git a/net/ipv4/syncookies.c b/net/ipv4/syncookies.c
> index 38f331da6677..07e201cc3d6a 100644
> --- a/net/ipv4/syncookies.c
> +++ b/net/ipv4/syncookies.c
> @@ -452,8 +456,10 @@ struct sock *cookie_v4_check(struct sock *sk, struct sk_buff *skb)
>  			   ireq->ir_loc_addr, th->source, th->dest, sk->sk_uid);
>  	security_req_classify_flow(req, flowi4_to_flowi_common(&fl4));
>  	rt = ip_route_output_key(net, &fl4);
> -	if (IS_ERR(rt))
> +	if (IS_ERR(rt)) {
> +		SKB_DR_SET(reason, IP_ROUTEOUTPUTKEY);

Reason names should be based on functional failures, not function names
which will change over time. In this case the failure is an output route
lookup which is basically SKB_DROP_REASON_IP_OUTNOROUTES
Jason Xing Feb. 13, 2024, 5:01 p.m. UTC | #2 
On Tue, Feb 13, 2024 at 11:56 PM David Ahern <dsahern@kernel.org> wrote:
>
> On 2/13/24 6:42 AM, Jason Xing wrote:
> > diff --git a/net/ipv4/syncookies.c b/net/ipv4/syncookies.c
> > index 38f331da6677..07e201cc3d6a 100644
> > --- a/net/ipv4/syncookies.c
> > +++ b/net/ipv4/syncookies.c
> > @@ -452,8 +456,10 @@ struct sock *cookie_v4_check(struct sock *sk, struct sk_buff *skb)
> >                          ireq->ir_loc_addr, th->source, th->dest, sk->sk_uid);
> >       security_req_classify_flow(req, flowi4_to_flowi_common(&fl4));
> >       rt = ip_route_output_key(net, &fl4);
> > -     if (IS_ERR(rt))
> > +     if (IS_ERR(rt)) {
> > +             SKB_DR_SET(reason, IP_ROUTEOUTPUTKEY);
>
> Reason names should be based on functional failures, not function names
> which will change over time. In this case the failure is an output route
> lookup which is basically SKB_DROP_REASON_IP_OUTNOROUTES

You're right. I'll update it soon :)

Thanks,
Jason

>
>
>
diff mbox series

Patch

diff --git a/net/ipv4/syncookies.c b/net/ipv4/syncookies.c
index 38f331da6677..07e201cc3d6a 100644
--- a/net/ipv4/syncookies.c
+++ b/net/ipv4/syncookies.c
@@ -421,8 +421,10 @@  struct sock *cookie_v4_check(struct sock *sk, struct sk_buff *skb)
 		if (IS_ERR(req))
 			goto out;
 	}
-	if (!req)
+	if (!req) {
+		SKB_DR_SET(reason, NO_REQSK_ALLOC);
 		goto out_drop;
+	}
 
 	ireq = inet_rsk(req);
 
@@ -434,8 +436,10 @@  struct sock *cookie_v4_check(struct sock *sk, struct sk_buff *skb)
 	 */
 	RCU_INIT_POINTER(ireq->ireq_opt, tcp_v4_save_options(net, skb));
 
-	if (security_inet_conn_request(sk, skb, req))
+	if (security_inet_conn_request(sk, skb, req)) {
+		SKB_DR_SET(reason, SECURITY_HOOK);
 		goto out_free;
+	}
 
 	tcp_ao_syncookie(sk, skb, req, AF_INET);
 
@@ -452,8 +456,10 @@  struct sock *cookie_v4_check(struct sock *sk, struct sk_buff *skb)
 			   ireq->ir_loc_addr, th->source, th->dest, sk->sk_uid);
 	security_req_classify_flow(req, flowi4_to_flowi_common(&fl4));
 	rt = ip_route_output_key(net, &fl4);
-	if (IS_ERR(rt))
+	if (IS_ERR(rt)) {
+		SKB_DR_SET(reason, IP_ROUTEOUTPUTKEY);
 		goto out_free;
+	}
 
 	/* Try to redo what tcp_v4_send_synack did. */
 	req->rsk_window_clamp = tp->window_clamp ? :dst_metric(&rt->dst, RTAX_WINDOW);
@@ -476,10 +482,12 @@  struct sock *cookie_v4_check(struct sock *sk, struct sk_buff *skb)
 	/* ip_queue_xmit() depends on our flow being setup
 	 * Normal sockets get it right from inet_csk_route_child_sock()
 	 */
-	if (ret)
+	if (ret) {
 		inet_sk(ret)->cork.fl.u.ip4 = fl4;
-	else
+	} else {
+		SKB_DR_SET(reason, COOKIE_NOCHILD);
 		goto out_drop;
+	}
 out:
 	return ret;
 out_free: