git: 87246654e350 - stable/13 - pfsync: locking fixes

[Kristof Provost]

The branch stable/13 has been updated by kp:

URL: 
https://cgit.FreeBSD.org/src/commit/?id=87246654e350e502a66fa74b731b8db3748cc1e8

commit 87246654e350e502a66fa74b731b8db3748cc1e8
Author:     Kristof Provost <k...@freebsd.org>
AuthorDate: 2021-12-02 16:42:56 +0000
Commit:     Kristof Provost <k...@freebsd.org>
CommitDate: 2021-12-13 13:49:27 +0000

    pfsync: locking fixes
    
     * Ensure we unlock the pfsync lock in pfsync_defer()
     * We must hold the bucket lock when calling pfsync_push()
     * The pfsync_defer_tmo() callout locks the bucket lock, not the pfsync
       lock
    
    Reviewed by:    glebius
    MFC after:      1 week
    Sponsored by:   Rubicon Communications, LLC ("Netgate")
    Differential Revision:  https://reviews.freebsd.org/D33243
    
    (cherry picked from commit 41c4f1987243cefe81adcc31d5401e7a80a0428c)
---
 sys/netpfil/pf/if_pfsync.c | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/sys/netpfil/pf/if_pfsync.c b/sys/netpfil/pf/if_pfsync.c
index a4f1d43f5ea0..455e1ad09e93 100644
--- a/sys/netpfil/pf/if_pfsync.c
+++ b/sys/netpfil/pf/if_pfsync.c
@@ -1751,12 +1751,17 @@ pfsync_defer(struct pf_kstate *st, struct mbuf *m)
                return (0);
        }
 
+       PFSYNC_BUCKET_LOCK(b);
+       PFSYNC_UNLOCK(sc);
+
        if (b->b_deferred >= 128)
                pfsync_undefer(TAILQ_FIRST(&b->b_deferrals), 0);
 
        pd = malloc(sizeof(*pd), M_PFSYNC, M_NOWAIT);
-       if (pd == NULL)
+       if (pd == NULL) {
+               PFSYNC_BUCKET_UNLOCK(b);
                return (0);
+       }
        b->b_deferred++;
 
        m->m_flags |= M_SKIP_FIREWALL;
@@ -1773,6 +1778,7 @@ pfsync_defer(struct pf_kstate *st, struct mbuf *m)
        callout_reset(&pd->pd_tmo, PFSYNC_DEFER_TIMEOUT, pfsync_defer_tmo, pd);
 
        pfsync_push(b);
+       PFSYNC_BUCKET_UNLOCK(b);
 
        return (1);
 }
@@ -1821,7 +1827,7 @@ pfsync_defer_tmo(void *arg)
        pd->pd_st->state_flags &= ~PFSTATE_ACK; /* XXX: locking! */
        if (pd->pd_refs == 0)
                free(pd, M_PFSYNC);
-       PFSYNC_UNLOCK(sc);
+       PFSYNC_BUCKET_UNLOCK(b);
 
        ip_output(m, NULL, NULL, 0, NULL, NULL);