git: 1d6ece4351a0 - stable/12 - pfsync: add missing unlock in pfsync_defer_tmo()

The branch stable/12 has been updated by kp:

URL: https://cgit.FreeBSD.org/src/commit/?id=1d6ece4351a01179e3a5ebbdb3fa2e6053a2d7aa

commit 1d6ece4351a01179e3a5ebbdb3fa2e6053a2d7aa
Author:     Kristof Provost <kp@FreeBSD.org>
AuthorDate: 2023-03-20 13:26:33 +0000
Commit:     Kristof Provost <kp@FreeBSD.org>
CommitDate: 2023-03-27 00:28:37 +0000

    pfsync: add missing unlock in pfsync_defer_tmo()
    
    The callout for pfsync_defer_tmo() is created with
    CALLOUT_RETURNUNLOCKED, because while the callout framework takes care
    of taking the lock we want to run a few operations outside of the lock,
    so we unlock ourselves.
    
    However, if `sc->sc_sync_if == NULL` we return without releasing the
    lock, and leak the lock, causing later deadlocks.
    Ensure we always release the bucket lock when we exit pfsync_defer_tmo()
    
    PR:             268246
    MFC after:      1 week
    Sponsored by:   Rubicon Communications, LLC (Netgate)
    
    (cherry picked from commit 844ad2828a35c434b893af4274b1f6c50332dd70)
---
 sys/netpfil/pf/if_pfsync.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/sys/netpfil/pf/if_pfsync.c b/sys/netpfil/pf/if_pfsync.c
index 6a67b8fe3d80..a73b4ff95c6a 100644
--- a/sys/netpfil/pf/if_pfsync.c
+++ b/sys/netpfil/pf/if_pfsync.c
@@ -1831,8 +1831,10 @@ pfsync_defer_tmo(void *arg)
 
 	PFSYNC_BUCKET_LOCK_ASSERT(b);
 
-	if (sc->sc_sync_if == NULL)
+	if (sc->sc_sync_if == NULL) {
+		PFSYNC_BUCKET_UNLOCK(b);
 		return;
+	}
 
 	CURVNET_SET(sc->sc_sync_if->if_vnet);