sctp: mark sctp_do_peeloff static

sctp_do_peeloff is only used inside of net/sctp/socket.c,
so mark it static.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Xin Long <lucien.xin@gmail.com>
Link: https://patch.msgid.link/20250526054745.2329201-1-hch@lst.de
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

Author: Christoph Hellwig

include/net/sctp/sctp.h

@@ -364,8 +364,6 @@ sctp_assoc_to_state(const struct sctp_association *asoc)
 /* Look up the association by its id.  */
 struct sctp_association *sctp_id2assoc(struct sock *sk, sctp_assoc_t id);
 
-int sctp_do_peeloff(struct sock *sk, sctp_assoc_t id, struct socket **sockp);
-
 /* A macro to walk a list of skbs.  */
 #define sctp_skb_for_each(pos, head, tmp) \
 	skb_queue_walk_safe(head, pos, tmp)

net/sctp/socket.c

@@ -5627,7 +5627,8 @@ static int sctp_getsockopt_autoclose(struct sock *sk, int len, char __user *optv
 }
 
 /* Helper routine to branch off an association to a new socket.  */
-int sctp_do_peeloff(struct sock *sk, sctp_assoc_t id, struct socket **sockp)
+static int sctp_do_peeloff(struct sock *sk, sctp_assoc_t id,
+		struct socket **sockp)
 {
 	struct sctp_association *asoc = sctp_id2assoc(sk, id);
 	struct sctp_sock *sp = sctp_sk(sk);
@@ -5675,7 +5676,6 @@ int sctp_do_peeloff(struct sock *sk, sctp_assoc_t id, struct socket **sockp)
 
 	return err;
 }
-EXPORT_SYMBOL(sctp_do_peeloff);
 
 static int sctp_getsockopt_peeloff_common(struct sock *sk, sctp_peeloff_arg_t *peeloff,
 					  struct file **newfile, unsigned flags)