From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id F1F97415F12; Tue, 21 Jul 2026 21:32:29 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784669551; cv=none; b=hxrTq2sRN1s9gfNnRmA7REQMpSZSEzfgQFbNbFA3c4WSVj36tmXcCfa7Rj/qIsiNHdcG/iEnCHPB40eMbe40+s/1i7zyoiFhMFNlFe66hOp8V7DT89hFwFJiT082Wk+vjHh0KUeqamBUVdUzATMZpMJXbMODPlZWIbr+Dy8ht30= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784669551; c=relaxed/simple; bh=vfTQglmcP+MrtR2//nhicHbfWX7m1uWy3dT6VHOzDSM=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=LvmC941TdYOr3TKlIf0VTiG3cHAM0JPxbn2v3//jmUhQLkOp8+ywhpUGQ6YU3ynOrkDD7srAxFPcjw6R7Za/Bba7Cch/3FydFYQdmfkBAZ/HZwmUNPm++kgc6Yjol8LeYOPBMJ+iDf89I2ysyAZjZZfQxxzPRQKhcZJRZxR9nOY= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=z4LgkdQ4; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="z4LgkdQ4" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 629381F00A3A; Tue, 21 Jul 2026 21:32:29 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1784669549; bh=nChqbfdqZREINBXwWEkKSAu+KtHzSHMFqp2QxHsD+hA=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=z4LgkdQ4Gheekm1cAUGxFGR9u7eU+xE49gBQ7YIzRadUjKjmoGg4LjFLSJGtElXLh WyuK8oc4vsHlAhNjhWBOgdD5rG5WgWcsc/a61wsN7BBHig0sX7+pcQSu6HrLzeqZPb KJXVjsQe0np7FFUZf+2U+1j5ADisqBj89iKFz348= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Jozsef Kadlecsik , Pablo Neira Ayuso , Sasha Levin Subject: [PATCH 6.1 0596/1067] netfilter: ipset: annotate "pos" for concurrent readers/writers Date: Tue, 21 Jul 2026 17:19:57 +0200 Message-ID: <20260721152437.938027093@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260721152424.521567757@linuxfoundation.org> References: <20260721152424.521567757@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.1-stable review patch. If anyone has any objections, please let me know. ------------------ From: Jozsef Kadlecsik [ Upstream commit 7f7445840b7771338618930e45ee641104b38ed8 ] The "pos" structure member of struct hbucket stores the first free slot in the hash bucket of a hash type of set and there are concurrent readers/writers. Annotate accesses properly. Fixes: 18f84d41d34f ("netfilter: ipset: Introduce RCU locking in hash:* types") Signed-off-by: Jozsef Kadlecsik Signed-off-by: Pablo Neira Ayuso Stable-dep-of: e4b4984e28c1 ("netfilter: ipset: Don't use test_bit() in lockless RCU readers in hash types") Signed-off-by: Sasha Levin --- net/netfilter/ipset/ip_set_hash_gen.h | 62 ++++++++++++++++----------- 1 file changed, 38 insertions(+), 24 deletions(-) diff --git a/net/netfilter/ipset/ip_set_hash_gen.h b/net/netfilter/ipset/ip_set_hash_gen.h index dea04887b8e699..25c51a8e2bfb12 100644 --- a/net/netfilter/ipset/ip_set_hash_gen.h +++ b/net/netfilter/ipset/ip_set_hash_gen.h @@ -373,8 +373,9 @@ static void mtype_ext_cleanup(struct ip_set *set, struct hbucket *n) { int i; + u8 pos = smp_load_acquire(&n->pos); - for (i = 0; i < n->pos; i++) + for (i = 0; i < pos; i++) if (test_bit(i, n->used)) ip_set_ext_destroy(set, ahash_data(n, i, set->dsize)); } @@ -477,7 +478,7 @@ mtype_gc_do(struct ip_set *set, struct htype *h, struct htable *t, u32 r) #ifdef IP_SET_HASH_WITH_NETS u8 k; #endif - u8 htable_bits = t->htable_bits; + u8 pos, htable_bits = t->htable_bits; spin_lock_bh(&t->hregion[r].lock); for (i = ahash_bucket_start(r, htable_bits); @@ -485,7 +486,8 @@ mtype_gc_do(struct ip_set *set, struct htype *h, struct htable *t, u32 r) n = __ipset_dereference(hbucket(t, i)); if (!n) continue; - for (j = 0, d = 0; j < n->pos; j++) { + pos = smp_load_acquire(&n->pos); + for (j = 0, d = 0; j < pos; j++) { if (!test_bit(j, n->used)) { d++; continue; @@ -521,7 +523,7 @@ mtype_gc_do(struct ip_set *set, struct htype *h, struct htable *t, u32 r) /* Still try to delete expired elements. */ continue; tmp->size = n->size - AHASH_INIT_SIZE; - for (j = 0, d = 0; j < n->pos; j++) { + for (j = 0, d = 0; j < pos; j++) { if (!test_bit(j, n->used)) continue; data = ahash_data(n, j, dsize); @@ -610,7 +612,7 @@ mtype_resize(struct ip_set *set, bool retried) { struct htype *h = set->data; struct htable *t, *orig; - u8 htable_bits; + u8 pos, htable_bits; size_t hsize, dsize = set->dsize; #ifdef IP_SET_HASH_WITH_NETS u8 flags; @@ -672,7 +674,8 @@ mtype_resize(struct ip_set *set, bool retried) n = __ipset_dereference(hbucket(orig, i)); if (!n) continue; - for (j = 0; j < n->pos; j++) { + pos = smp_load_acquire(&n->pos); + for (j = 0; j < pos; j++) { if (!test_bit(j, n->used)) continue; data = ahash_data(n, j, dsize); @@ -796,9 +799,10 @@ mtype_ext_size(struct ip_set *set, u32 *elements, size_t *ext_size) { struct htype *h = set->data; const struct htable *t; - u32 i, j, r; struct hbucket *n; struct mtype_elem *data; + u32 i, j, r; + u8 pos; t = rcu_dereference_bh(h->table); for (r = 0; r < ahash_numof_locks(t->htable_bits); r++) { @@ -807,7 +811,8 @@ mtype_ext_size(struct ip_set *set, u32 *elements, size_t *ext_size) n = rcu_dereference_bh(hbucket(t, i)); if (!n) continue; - for (j = 0; j < n->pos; j++) { + pos = smp_load_acquire(&n->pos); + for (j = 0; j < pos; j++) { if (!test_bit(j, n->used)) continue; data = ahash_data(n, j, set->dsize); @@ -831,10 +836,11 @@ mtype_add(struct ip_set *set, void *value, const struct ip_set_ext *ext, const struct mtype_elem *d = value; struct mtype_elem *data; struct hbucket *n, *old = ERR_PTR(-ENOENT); - int i, j = -1, npos = 0, ret; + int i, j = -1, ret; bool flag_exist = flags & IPSET_FLAG_EXIST; bool deleted = false, forceadd = false, reuse = false; u32 r, key, multi = 0, elements, maxelem; + u8 npos = 0; rcu_read_lock_bh(); t = rcu_dereference_bh(h->table); @@ -876,8 +882,8 @@ mtype_add(struct ip_set *set, void *value, const struct ip_set_ext *ext, ext_size(AHASH_INIT_SIZE, set->dsize); goto copy_elem; } - npos = n->pos; - for (i = 0; i < n->pos; i++) { + npos = smp_load_acquire(&n->pos); + for (i = 0; i < npos; i++) { if (!test_bit(i, n->used)) { /* Reuse first deleted entry */ if (j == -1) { @@ -921,7 +927,7 @@ mtype_add(struct ip_set *set, void *value, const struct ip_set_ext *ext, if (elements >= maxelem) goto set_full; /* Create a new slot */ - if (n->pos >= n->size) { + if (npos >= n->size) { #ifdef IP_SET_HASH_WITH_MULTI if (h->bucketsize >= AHASH_MAX_TUNED) goto set_full; @@ -950,8 +956,7 @@ mtype_add(struct ip_set *set, void *value, const struct ip_set_ext *ext, } copy_elem: - j = npos; - npos = n->pos + 1; + j = npos++; data = ahash_data(n, j, set->dsize); copy_data: t->hregion[r].elements++; @@ -974,7 +979,8 @@ mtype_add(struct ip_set *set, void *value, const struct ip_set_ext *ext, if (SET_WITH_TIMEOUT(set)) ip_set_timeout_set(ext_timeout(data, set), ext->timeout); smp_mb__before_atomic(); - n->pos = npos; + /* Ensure all data writes are visible before updating position */ + smp_store_release(&n->pos, npos); set_bit(j, n->used); if (old != ERR_PTR(-ENOENT)) { rcu_assign_pointer(hbucket(t, key), n); @@ -1033,6 +1039,7 @@ mtype_del(struct ip_set *set, void *value, const struct ip_set_ext *ext, int i, j, k, r, ret = -IPSET_ERR_EXIST; u32 key, multi = 0; size_t dsize = set->dsize; + u8 pos; /* Userspace add and resize is excluded by the mutex. * Kernespace add does not trigger resize. @@ -1048,7 +1055,8 @@ mtype_del(struct ip_set *set, void *value, const struct ip_set_ext *ext, n = rcu_dereference_bh(hbucket(t, key)); if (!n) goto out; - for (i = 0, k = 0; i < n->pos; i++) { + pos = smp_load_acquire(&n->pos); + for (i = 0, k = 0; i < pos; i++) { if (!test_bit(i, n->used)) { k++; continue; @@ -1062,8 +1070,8 @@ mtype_del(struct ip_set *set, void *value, const struct ip_set_ext *ext, ret = 0; clear_bit(i, n->used); smp_mb__after_atomic(); - if (i + 1 == n->pos) - n->pos--; + if (i + 1 == pos) + smp_store_release(&n->pos, --pos); t->hregion[r].elements--; #ifdef IP_SET_HASH_WITH_NETS for (j = 0; j < IPSET_NET_COUNT; j++) @@ -1085,11 +1093,11 @@ mtype_del(struct ip_set *set, void *value, const struct ip_set_ext *ext, x->flags = flags; } } - for (; i < n->pos; i++) { + for (; i < pos; i++) { if (!test_bit(i, n->used)) k++; } - if (k == n->pos) { + if (k == pos) { t->hregion[r].ext_size -= ext_size(n->size, dsize); rcu_assign_pointer(hbucket(t, key), NULL); kfree_rcu(n, rcu); @@ -1100,7 +1108,7 @@ mtype_del(struct ip_set *set, void *value, const struct ip_set_ext *ext, if (!tmp) goto out; tmp->size = n->size - AHASH_INIT_SIZE; - for (j = 0, k = 0; j < n->pos; j++) { + for (j = 0, k = 0; j < pos; j++) { if (!test_bit(j, n->used)) continue; data = ahash_data(n, j, dsize); @@ -1161,6 +1169,7 @@ mtype_test_cidrs(struct ip_set *set, struct mtype_elem *d, int ret, i, j = 0; #endif u32 key, multi = 0; + u8 pos; pr_debug("test by nets\n"); for (; j < NLEN && h->nets[j].cidr[0] && !multi; j++) { @@ -1178,7 +1187,8 @@ mtype_test_cidrs(struct ip_set *set, struct mtype_elem *d, n = rcu_dereference_bh(hbucket(t, key)); if (!n) continue; - for (i = 0; i < n->pos; i++) { + pos = smp_load_acquire(&n->pos); + for (i = 0; i < pos; i++) { if (!test_bit(i, n->used)) continue; data = ahash_data(n, i, set->dsize); @@ -1212,6 +1222,7 @@ mtype_test(struct ip_set *set, void *value, const struct ip_set_ext *ext, struct mtype_elem *data; int i, ret = 0; u32 key, multi = 0; + u8 pos; rcu_read_lock_bh(); t = rcu_dereference_bh(h->table); @@ -1234,7 +1245,8 @@ mtype_test(struct ip_set *set, void *value, const struct ip_set_ext *ext, ret = 0; goto out; } - for (i = 0; i < n->pos; i++) { + pos = smp_load_acquire(&n->pos); + for (i = 0; i < pos; i++) { if (!test_bit(i, n->used)) continue; data = ahash_data(n, i, set->dsize); @@ -1339,6 +1351,7 @@ mtype_list(const struct ip_set *set, /* We assume that one hash bucket fills into one page */ void *incomplete; int i, ret = 0; + u8 pos; atd = nla_nest_start(skb, IPSET_ATTR_ADT); if (!atd) @@ -1357,7 +1370,8 @@ mtype_list(const struct ip_set *set, cb->args[IPSET_CB_ARG0], t, n); if (!n) continue; - for (i = 0; i < n->pos; i++) { + pos = smp_load_acquire(&n->pos); + for (i = 0; i < pos; i++) { if (!test_bit(i, n->used)) continue; e = ahash_data(n, i, set->dsize); -- 2.53.0