pf: fix mem leaks upon vnet destroy

Add missing cleanup actions:
- remove user defined anchor rulesets
- remove user defined ether anchor rulesets
- remove tables linked to user defined anchors
- deal with wildcard anchor peculiarities to get them removed correctly

PR:		274310
Reviewed by:	kp
MFC after:	1 week
Differential Revision:	https://reviews.freebsd.org/D42747

(cherry picked from commit 0626d30e41cba64b41667314c3a4f7611f0eb685)

1 files changed, 38 insertions, 6 deletions

diff --git a/sys/netpfil/pf/pf_ioctl.c b/sys/netpfil/pf/pf_ioctl.c
index 639c2462fe75..81b766cb7f6a 100644
--- a/sys/netpfil/pf/pf_ioctl.c
+++ b/sys/netpfil/pf/pf_ioctl.c
@@ -5089,6 +5089,7 @@ pf_clear_tables(void)
 	int error;
 
 	bzero(&io, sizeof(io));
+	io.pfrio_flags |= PFR_FLAG_ALLRSETS;
 
 	error = pfr_clr_tables(&io.pfrio_table, &io.pfrio_ndel,
 	    io.pfrio_flags);
@@ -5499,8 +5500,34 @@ shutdown_pf(void)
 	int error = 0;
 	u_int32_t t[5];
 	char nn = '\0';
+	struct pf_kanchor *anchor;
+	int rs_num;
 
 	do {
+		/* Unlink rules of all user defined anchors */
+		RB_FOREACH(anchor, pf_kanchor_global, &V_pf_anchors) {
+			/* Wildcard based anchors may not have a respective
+			 * explicit anchor rule or they may be left empty
+			 * without rules. It leads to anchor.refcnt=0, and the
+			 * rest of the logic does not expect it. */
+			if (anchor->refcnt == 0)
+				anchor->refcnt = 1;
+			for (rs_num = 0; rs_num < PF_RULESET_MAX; ++rs_num) {
+				if ((error = pf_begin_rules(&t[rs_num], rs_num,
+				    anchor->path)) != 0) {
+					DPFPRINTF(PF_DEBUG_MISC, ("shutdown_pf: "
+					    "anchor.path=%s rs_num=%d\n",
+					    anchor->path, rs_num));
+					goto error;	/* XXX: rollback? */
+				}
+			}
+			for (rs_num = 0; rs_num < PF_RULESET_MAX; ++rs_num) {
+				error = pf_commit_rules(t[rs_num], rs_num,
+				    anchor->path);
+				MPASS(error == 0);
+			}
+		}
+
 		if ((error = pf_begin_rules(&t[0], PF_RULESET_SCRUB, &nn))
 		    != 0) {
 			DPFPRINTF(PF_DEBUG_MISC, ("shutdown_pf: SCRUB\n"));
@@ -5527,12 +5554,16 @@ shutdown_pf(void)
 			break;		/* XXX: rollback? */
 		}
 
-		/* XXX: these should always succeed here */
-		pf_commit_rules(t[0], PF_RULESET_SCRUB, &nn);
-		pf_commit_rules(t[1], PF_RULESET_FILTER, &nn);
-		pf_commit_rules(t[2], PF_RULESET_NAT, &nn);
-		pf_commit_rules(t[3], PF_RULESET_BINAT, &nn);
-		pf_commit_rules(t[4], PF_RULESET_RDR, &nn);
+		error = pf_commit_rules(t[0], PF_RULESET_SCRUB, &nn);
+		MPASS(error == 0);
+		error = pf_commit_rules(t[1], PF_RULESET_FILTER, &nn);
+		MPASS(error == 0);
+		error = pf_commit_rules(t[2], PF_RULESET_NAT, &nn);
+		MPASS(error == 0);
+		error = pf_commit_rules(t[3], PF_RULESET_BINAT, &nn);
+		MPASS(error == 0);
+		error = pf_commit_rules(t[4], PF_RULESET_RDR, &nn);
+		MPASS(error == 0);
 
 		if ((error = pf_clear_tables()) != 0)
 			break;
@@ -5553,6 +5584,7 @@ shutdown_pf(void)
 		/* fingerprints and interfaces have their own cleanup code */
 	} while(0);
 
+error:
 	return (error);
 }