git: bbbe18b31795 - stable/12 - pfsync: NULL check sc before using it

The branch stable/12 has been updated by kp:

URL: https://cgit.FreeBSD.org/src/commit/?id=bbbe18b317956f3e0d87a277acc1941222fa8eb9

commit bbbe18b317956f3e0d87a277acc1941222fa8eb9
Author:     Kristof Provost <kp@FreeBSD.org>
AuthorDate: 2021-12-02 13:32:21 +0000
Commit:     Kristof Provost <kp@FreeBSD.org>
CommitDate: 2021-12-13 08:54:15 +0000

    pfsync: NULL check sc before using it
    
    In pfsync_defer() we must wait to lock sc until we've ensured it's not
    NULL.
    
    MFC after:      1 week
    Sponsored by:   Rubicon Communications, LLC ("Netgate")
    Differential Revision:  https://reviews.freebsd.org/D33240
    
    (cherry picked from commit 27bd812c5c92af9e7acdbf100bd98166a717bb76)
---
 sys/netpfil/pf/if_pfsync.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/sys/netpfil/pf/if_pfsync.c b/sys/netpfil/pf/if_pfsync.c
index 8feaea615867..d6016766ddcc 100644
--- a/sys/netpfil/pf/if_pfsync.c
+++ b/sys/netpfil/pf/if_pfsync.c
@@ -1741,9 +1741,12 @@ pfsync_defer(struct pf_kstate *st, struct mbuf *m)
 	if (m->m_flags & (M_BCAST|M_MCAST))
 		return (0);
 
+	if (sc == NULL)
+		return (0);
+
 	PFSYNC_LOCK(sc);
 
-	if (sc == NULL || !(sc->sc_ifp->if_flags & IFF_DRV_RUNNING) ||
+	if (!(sc->sc_ifp->if_flags & IFF_DRV_RUNNING) ||
 	    !(sc->sc_flags & PFSYNCF_DEFER)) {
 		PFSYNC_UNLOCK(sc);
 		return (0);