Module Name: src
Committed By: riastradh
Date: Mon Jul 29 19:44:23 UTC 2024
Modified Files:
src/sys/net: if_wg.c
Log Message:
wg(4): Add missing barriers around wgp_pending access.
PR kern/58520: experimental wg(4) lacks barriers around access to
packet pending initiation
To generate a diff of this commit:
cvs rdiff -u -r1.124 -r1.125 src/sys/net/if_wg.c
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: src/sys/net/if_wg.c
diff -u src/sys/net/if_wg.c:1.124 src/sys/net/if_wg.c:1.125
--- src/sys/net/if_wg.c:1.124 Mon Jul 29 19:43:56 2024
+++ src/sys/net/if_wg.c Mon Jul 29 19:44:22 2024
@@ -1,4 +1,4 @@
-/* $NetBSD: if_wg.c,v 1.124 2024/07/29 19:43:56 riastradh Exp $ */
+/* $NetBSD: if_wg.c,v 1.125 2024/07/29 19:44:22 riastradh Exp $ */
/*
* Copyright (C) Ryota Ozaki <ozaki.ry...@gmail.com>
@@ -41,7 +41,7 @@
*/
#include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: if_wg.c,v 1.124 2024/07/29 19:43:56 riastradh Exp $");
+__KERNEL_RCSID(0, "$NetBSD: if_wg.c,v 1.125 2024/07/29 19:44:22 riastradh Exp $");
#ifdef _KERNEL_OPT
#include "opt_altq_enabled.h"
@@ -1911,6 +1911,7 @@ wg_send_handshake_msg_init(struct wg_sof
WG_DLOG("send_hs_msg failed, error=%d\n", error);
wg_put_session_index(wg, wgs);
m = atomic_swap_ptr(&wgp->wgp_pending, NULL);
+ membar_acquire(); /* matches membar_release in wg_output */
m_freem(m);
return;
}
@@ -2081,6 +2082,7 @@ wg_swap_sessions(struct wg_softc *wg, st
* or else the responder will never answer.
*/
if ((m = atomic_swap_ptr(&wgp->wgp_pending, NULL)) != NULL) {
+ membar_acquire(); /* matches membar_release in wg_output */
kpreempt_disable();
const uint32_t h = curcpu()->ci_index; // pktq_rps_hash(m)
M_SETCTX(m, wgp);
@@ -3730,6 +3732,7 @@ wg_purge_pending_packets(struct wg_peer
struct mbuf *m;
m = atomic_swap_ptr(&wgp->wgp_pending, NULL);
+ membar_acquire(); /* matches membar_release in wg_output */
m_freem(m);
#ifdef ALTQ
wg_start(&wgp->wgp_sc->wg_if);
@@ -4247,11 +4250,17 @@ wg_output(struct ifnet *ifp, struct mbuf
* just drop the packet and let the ongoing handshake
* attempt continue. We could queue more data packets
* but it's not clear that's worthwhile.
+ *
+ * membar_release matches membar_acquire in
+ * wg_swap_sessions, wg_purge_pending_packets, and
+ * wg_send_handshake_msg_init.
*/
+ membar_release();
if ((m = atomic_swap_ptr(&wgp->wgp_pending, m)) == NULL) {
WG_TRACE("queued first packet; init handshake");
wg_schedule_peer_task(wgp, WGP_TASK_SEND_INIT_MESSAGE);
} else {
+ membar_acquire();
WG_TRACE("first packet already queued, dropping");
}
goto out1;
