git: fb81855f1981 - stable/15 - routing: Fix table sizes

The branch stable/15 has been updated by des:

URL: https://cgit.FreeBSD.org/src/commit/?id=fb81855f198198a9035bf68196dba5f67662d0ff

commit fb81855f198198a9035bf68196dba5f67662d0ff
Author:     Dag-Erling Smørgrav <des@FreeBSD.org>
AuthorDate: 2026-08-13 21:45:53 +0000
Commit:     Dag-Erling Smørgrav <des@FreeBSD.org>
CommitDate: 2026-08-16 20:24:58 +0000

    routing: Fix table sizes
    
    Tables that have one element per protocol or address family were
    previously sized by AF_MAX + 1 since AF_MAX was off by one.  Now that
    AF_MAX has been corrected, we need to apply the opposite correction to
    these tables.
    
    Fixes:          ddd850aa7720 ("sys/socket.h: Fix AF_MAX")
    MFC after:      3 days
    Sponsored by:   Klara, Inc.
    Sponsored by:   NetApp, Inc.
    Reviewed by:    pouria, kevans, glebius
    Differential Revision:  https://reviews.freebsd.org/D58826
    
    (cherry picked from commit 6c41d928bcd763ec60d55bec2886c05b03cf9e6a)
---
 sys/net/route/route_tables.c | 18 +++++++++---------
 1 file changed, 9 insertions(+), 9 deletions(-)

diff --git a/sys/net/route/route_tables.c b/sys/net/route/route_tables.c
index fdcb775ac4ce..66b3df23e944 100644
--- a/sys/net/route/route_tables.c
+++ b/sys/net/route/route_tables.c
@@ -204,7 +204,7 @@ static void
 populate_kernel_routes(struct rib_head **new_rt_tables, struct rib_head *rh)
 {
 	for (int i = 0; i < V_rt_numfibs; i++) {
-		struct rib_head *rh_src = new_rt_tables[i * (AF_MAX + 1) + rh->rib_family];
+		struct rib_head *rh_src = new_rt_tables[i * AF_MAX + rh->rib_family];
 		if ((rh_src != NULL) && (rh_src != rh))
 			rib_copy_kernel_routes(rh_src, rh);
 	}
@@ -228,7 +228,7 @@ grow_rtables(uint32_t num_tables)
 	KASSERT(num_tables >= V_rt_numfibs, ("num_tables(%u) < rt_numfibs(%u)\n",
 				num_tables, V_rt_numfibs));
 
-	new_rt_tables = mallocarray(num_tables * (AF_MAX + 1), sizeof(void *),
+	new_rt_tables = mallocarray(num_tables * AF_MAX, sizeof(void *),
 	    M_RTABLE, M_WAITOK | M_ZERO);
 
 #ifdef FIB_ALGO
@@ -237,12 +237,12 @@ grow_rtables(uint32_t num_tables)
 
 	/*
 	 * Current rt_tables layout:
-	 * fib0[af0, af1, af2, .., AF_MAX]fib1[af0, af1, af2, .., Af_MAX]..
+	 * fib0[af0, af1, af2, .., AF_MAX-1]fib1[af0, af1, af2, .., AF_MAX-1]..
 	 * this allows to copy existing tables data by using memcpy()
 	 */
 	if (V_rt_tables != NULL)
 		memcpy(new_rt_tables, V_rt_tables,
-		    V_rt_numfibs * (AF_MAX + 1) * sizeof(void *));
+		    V_rt_numfibs * AF_MAX * sizeof(void *));
 
 	/* Populate the remainders */
 	SLIST_FOREACH(dom, &domains, dom_next) {
@@ -250,7 +250,7 @@ grow_rtables(uint32_t num_tables)
 			continue;
 		family = dom->dom_family;
 		for (int i = 0; i < num_tables; i++) {
-			prnh = &new_rt_tables[i * (AF_MAX + 1) + family];
+			prnh = &new_rt_tables[i * AF_MAX + family];
 			if (*prnh != NULL)
 				continue;
 			rh = dom->dom_rtattach(i);
@@ -374,13 +374,13 @@ rt_tables_get_rnh_ptr(uint32_t table, sa_family_t family)
 	KASSERT(table < V_rt_numfibs,
 	    ("%s: table out of bounds (%d < %d)", __func__, table,
 	     V_rt_numfibs));
-	KASSERT(family < (AF_MAX + 1),
-	    ("%s: fam out of bounds (%d < %d)", __func__, family, AF_MAX + 1));
+	KASSERT(family < AF_MAX,
+	    ("%s: fam out of bounds (%d < %d)", __func__, family, AF_MAX));
 
 	/* rnh is [fib=0][af=0]. */
 	prnh = V_rt_tables;
 	/* Get the offset to the requested table and fam. */
-	prnh += table * (AF_MAX + 1) + family;
+	prnh += table * AF_MAX + family;
 
 	return (*prnh);
 }
@@ -397,7 +397,7 @@ rt_tables_get_rnh_safe(uint32_t table, sa_family_t family)
 {
 	if (__predict_false(table >= V_rt_numfibs))
 		return (NULL);
-	if (__predict_false(family >= (AF_MAX + 1)))
+	if (__predict_false(family >= AF_MAX))
 		return (NULL);
 	return (rt_tables_get_rnh_ptr(table, family));
 }