diff mbox series

[net-next,2/5] net_sched: sch_fq: prepare for TIME_WAIT sockets

Message ID 20241004191644.1687638-3-edumazet@google.com (mailing list archive)
State Superseded
Delegated to: Netdev Maintainers
Headers show
Series tcp: add skb->sk to more control packets | expand

Checks

Context Check Description
netdev/series_format success Posting correctly formatted
netdev/tree_selection success Clearly marked for net-next, async
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: 19 this patch: 19
netdev/build_tools success Errors and warnings before: 0 (+2) this patch: 0 (+2)
netdev/cc_maintainers warning 3 maintainers not CCed: jhs@mojatatu.com jiri@resnulli.us xiyou.wangcong@gmail.com
netdev/build_clang success Errors and warnings before: 39 this patch: 39
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: 2620 this patch: 2620
netdev/checkpatch warning WARNING: line length of 89 exceeds 80 columns
netdev/build_clang_rust success No Rust files in patch. Skipping build
netdev/kdoc success Errors and warnings before: 4 this patch: 4
netdev/source_inline success Was 0 now: 0

Commit Message

Eric Dumazet Oct. 4, 2024, 7:16 p.m. UTC 
TCP stack is not attaching skb to TIME_WAIT sockets yet,
but we would like to allow this in the future.

Add sk_listener_or_tw() helper to detect the three states
that FQ needs to take care.

Like NEW_SYN_RECV, TIME_WAIT are not full sockets and
do not contain sk->sk_pacing_status, sk->sk_pacing_rate.

Signed-off-by: Eric Dumazet <edumazet@google.com>
---
 include/net/sock.h | 10 ++++++++++
 net/sched/sch_fq.c |  3 ++-
 2 files changed, 12 insertions(+), 1 deletion(-)
diff mbox series

Patch

diff --git a/include/net/sock.h b/include/net/sock.h
index c58ca8dd561b7312ffc0836585c04d9fe917a124..c868b8b57e3489cd81efafa3856da09397059080 100644
--- a/include/net/sock.h
+++ b/include/net/sock.h
@@ -2784,6 +2784,16 @@  static inline bool sk_listener(const struct sock *sk)
 	return (1 << sk->sk_state) & (TCPF_LISTEN | TCPF_NEW_SYN_RECV);
 }
 
+/* This helper checks if a socket is a LISTEN or NEW_SYN_RECV or TIME_WAIT
+ * TCP SYNACK messages can be attached to LISTEN or NEW_SYN_RECV (depending on SYNCOOKIE)
+ * TCP RST and ACK can be attached to TIME_WAIT.
+ */
+static inline bool sk_listener_or_tw(const struct sock *sk)
+{
+	return (1 << READ_ONCE(sk->sk_state)) &
+	       (TCPF_LISTEN | TCPF_NEW_SYN_RECV | TCPF_TIME_WAIT);
+}
+
 void sock_enable_timestamp(struct sock *sk, enum sock_flags flag);
 int sock_recv_errqueue(struct sock *sk, struct msghdr *msg, int len, int level,
 		       int type);
diff --git a/net/sched/sch_fq.c b/net/sched/sch_fq.c
index 19a49af5a9e527ed0371a3bb96e0113755375eac..e10e94fa5f9bc17a086173abaacb57269bc506a8 100644
--- a/net/sched/sch_fq.c
+++ b/net/sched/sch_fq.c
@@ -361,8 +361,9 @@  static struct fq_flow *fq_classify(struct Qdisc *sch, struct sk_buff *skb,
 	 * 3) We do not want to rate limit them (eg SYNFLOOD attack),
 	 *    especially if the listener set SO_MAX_PACING_RATE
 	 * 4) We pretend they are orphaned
+	 * TCP can also associate TIME_WAIT sockets with RST or ACK packets.
 	 */
-	if (!sk || sk_listener(sk)) {
+	if (!sk || sk_listener_or_tw(sk)) {
 		unsigned long hash = skb_get_hash(skb) & q->orphan_mask;
 
 		/* By forcing low order bit to 1, we make sure to not