sctp: delete free member from struct sctp_sched_ops

After commit 9ed7bfc79542 ("sctp: fix memory leak in
sctp_stream_outq_migrate()"), sctp_sched_set_sched() is the only
place calling sched->free(), and it can actually be replaced by
sched->free_sid() on each stream, and yet there's already a loop
to traverse all streams in sctp_sched_set_sched().

This patch adds a function sctp_sched_free_sched() where it calls
sched->free_sid() for each stream to replace sched->free() calls
in sctp_sched_set_sched() and then deletes the unused free member
from struct sctp_sched_ops.

Signed-off-by: Xin Long <lucien.xin@gmail.com>
Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Link: https://lore.kernel.org/r/e10aac150aca2686cb0bd0570299ec716da5a5c0.1669849471.git.lucien.xin@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

1 files changed, 20 insertions, 18 deletions

diff --git a/net/sctp/stream_sched.c b/net/sctp/stream_sched.c
index 7c8f9d89e16a..330067002deb 100644
--- a/net/sctp/stream_sched.c
+++ b/net/sctp/stream_sched.c
@@ -50,10 +50,6 @@ static void sctp_sched_fcfs_free_sid(struct sctp_stream *stream, __u16 sid)
 {
 }
 
-static void sctp_sched_fcfs_free(struct sctp_stream *stream)
-{
-}
-
 static void sctp_sched_fcfs_enqueue(struct sctp_outq *q,
 				    struct sctp_datamsg *msg)
 {
@@ -101,7 +97,6 @@ static struct sctp_sched_ops sctp_sched_fcfs = {
 	.init = sctp_sched_fcfs_init,
 	.init_sid = sctp_sched_fcfs_init_sid,
 	.free_sid = sctp_sched_fcfs_free_sid,
-	.free = sctp_sched_fcfs_free,
 	.enqueue = sctp_sched_fcfs_enqueue,
 	.dequeue = sctp_sched_fcfs_dequeue,
 	.dequeue_done = sctp_sched_fcfs_dequeue_done,
@@ -131,6 +126,23 @@ void sctp_sched_ops_init(void)
 	sctp_sched_ops_rr_init();
 }
 
+static void sctp_sched_free_sched(struct sctp_stream *stream)
+{
+	struct sctp_sched_ops *sched = sctp_sched_ops_from_stream(stream);
+	struct sctp_stream_out_ext *soute;
+	int i;
+
+	sched->unsched_all(stream);
+	for (i = 0; i < stream->outcnt; i++) {
+		soute = SCTP_SO(stream, i)->ext;
+		if (!soute)
+			continue;
+		sched->free_sid(stream, i);
+		/* Give the next scheduler a clean slate. */
+		memset_after(soute, 0, outq);
+	}
+}
+
 int sctp_sched_set_sched(struct sctp_association *asoc,
 			 enum sctp_sched_type sched)
 {
@@ -146,18 +158,8 @@ int sctp_sched_set_sched(struct sctp_association *asoc,
 	if (sched > SCTP_SS_MAX)
 		return -EINVAL;
 
-	if (old) {
-		old->free(&asoc->stream);
-
-		/* Give the next scheduler a clean slate. */
-		for (i = 0; i < asoc->stream.outcnt; i++) {
-			struct sctp_stream_out_ext *ext = SCTP_SO(&asoc->stream, i)->ext;
-
-			if (!ext)
-				continue;
-			memset_after(ext, 0, outq);
-		}
-	}
+	if (old)
+		sctp_sched_free_sched(&asoc->stream);
 
 	asoc->outqueue.sched = n;
 	n->init(&asoc->stream);
@@ -181,7 +183,7 @@ int sctp_sched_set_sched(struct sctp_association *asoc,
 	return ret;
 
 err:
-	n->free(&asoc->stream);
+	sctp_sched_free_sched(&asoc->stream);
 	asoc->outqueue.sched = &sctp_sched_fcfs; /* Always safe */
 
 	return ret;