FAILED: patch "[PATCH] netfilter: nf_tables: skip expired catchall elements on" failed to apply to 6.1-stable tree

PATCH New [email protected] 2 participants 3 messages Sep 29 – Sep 30

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Networking Stable branch netfilter

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[email protected]

author maintainer

2026-09-29 09:39 UTC #0 lore raw

The patch below does not apply to the 6.1-stable tree.
If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <[email protected]>.

To reproduce the conflict and resubmit, you may use the following commands:

git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.1.y
git checkout FETCH_HEAD
git cherry-pick -x 70194dc37670bd08e44b471389861cc01bd3a3c9
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<[email protected]>' --in-reply-to '2026092923-thievish-makeshift-9a83@gregkh' --subject-prefix 'PATCH 6.1.y' 'HEAD^..'

Possible dependencies:

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From 70194dc37670bd08e44b471389861cc01bd3a3c9 Mon Sep 17 00:00:00 2001
From: Aohan Mei <[email protected]>
Date: Mon, 14 Sep 2026 19:51:47 +0800
Subject: [PATCH] netfilter: nf_tables: skip expired catchall elements on
insert and delete

nft_setelem_catchall_insert() looks up duplicates with nft_set_elem_active() only, while nft_set_catchall_lookup() and the dump path additionally skip expired elements.

Once a catchall element with a timeout expires, this predicate drift makes it invisible to userspace dumps, yet it still blocks
re-insertion: with NLM_F_EXCL the request fails with -EEXIST, and without it the request reports success but silently inserts nothing. The stale entry only goes away when the (user-tunable) gc interval elapses, so the catchall rule may silently stop matching for an arbitrarily long time after its first expiration.

The delete path shows the same drift: nft_setelem_catchall_deactivate() picks the first active-next entry in the catchall list, so with an expired entry still pending GC it retires the stale entry instead of the fresh one, and it deactivates an element that userspace no longer sees instead of failing with -ENOENT.

Align both walks with the lookup and dump predicates: only an element that is active and not expired counts as a duplicate or delete candidate, using the per-netns timestamp taken at transaction start, in line with the set backend .insert/.deactivate and catchall GC sync paths.

Reported-by TencentOS Corvus AI <[email protected]>

Cc [email protected]

Fixes aaa31047a6d2 ("netfilter: nftables: add catch-all set element support")

Assisted-by CodeBuddy:Kimi-K3

Signed-off-by Aohan Mei <[email protected]>

Signed-off-by Pablo Neira Ayuso <[email protected]>

net/netfilter/nf_tables_api.c +8 -2

index c0b754a2d45b..b59628e6240c 100644
@@ -6995,11 +6995,14 @@ static int nft_setelem_catchall_insert(const struct net *net,
 {
 	struct nft_set_elem_catchall *catchall;
 	u8 genmask = nft_genmask_next(net);
+	u64 tstamp = nft_net_tstamp(net);
 	struct nft_set_ext *ext;
 
 	list_for_each_entry(catchall, &set->catchall_list, list) {
 		ext = nft_set_elem_ext(set, catchall->elem);
-		if (nft_set_elem_active(ext, genmask)) {
+		if (nft_set_elem_active(ext, genmask) &&
+		    !__nft_set_elem_expired(ext, tstamp) &&
+		    !nft_set_elem_is_dead(ext)) {
 			*priv = catchall->elem;
 			return -EEXIST;
 		}

@@ -7092,11 +7095,14 @@ static int nft_setelem_catchall_deactivate(const struct net *net,
 					   struct nft_set_elem *elem)
 {
 	struct nft_set_elem_catchall *catchall;
+	u64 tstamp = nft_net_tstamp(net);
 	struct nft_set_ext *ext;
 
 	list_for_each_entry(catchall, &set->catchall_list, list) {
 		ext = nft_set_elem_ext(set, catchall->elem);
-		if (!nft_is_active_next(net, ext))
+		if (!nft_is_active_next(net, ext) ||
+		    __nft_set_elem_expired(ext, tstamp) ||
+		    nft_set_elem_is_dead(ext))
 			continue;
 
 		kfree(elem->priv);

Sasha Levin

maintainer

2026-09-30 14:05 UTC #1 lore raw

PATCH 1/2 netfilter: nf_tables: set->ops->insert returns opaque set element in case of EEXIST

From: Pablo Neira Ayuso <[email protected]>

[ Upstream commit 078996fcd657e6e0c3a72b7d5806d04c32e74250 ]

Return struct nft_elem_priv instead of struct nft_set_ext for consistency with ("netfilter: nf_tables: expose opaque set element as struct nft_elem_priv") and to prepare the introduction of element timeout updates from control path.

Signed-off-by Pablo Neira Ayuso <[email protected]>

Backport notes for Linux 6.1:
Keep the existing void-pointer representation of opaque set elements. The typed nft_elem_priv API and embedded priv members are not present in this branch, so return backend element pointers through void ** and derive the extension with nft_set_elem_ext() in the EEXIST handling path.

Preserve the stable set_full accounting and PIPAPO's early initialization of e, and omit the unrelated timeout declaration reorder. No functions or new element representations are introduced. This prepares the catchall insert context for 70194dc37670 ("netfilter: nf_tables: skip expired catchall elements on insert and delete"); its timestamp and expiration helpers already exist in this branch.

Stable-dep-of: 70194dc37670 ("netfilter: nf_tables: skip expired catchall elements on insert and delete")

Signed-off-by Sasha Levin <[email protected]>

---
 include/net/netfilter/nf_tables.h |  2 +-
 net/netfilter/nf_tables_api.c     | 15 +++++++++------
 net/netfilter/nft_set_bitmap.c    |  4 ++--
 net/netfilter/nft_set_hash.c      |  8 ++++----
 net/netfilter/nft_set_pipapo.c    | 10 +++++-----
 net/netfilter/nft_set_rbtree.c    | 10 +++++-----
 6 files changed, 26 insertions(+), 23 deletions(-)

include/net/netfilter/nf_tables.h +1 -1

index 7e63281f2d5a8..b8f283a6e718f 100644
@@ -454,7 +454,7 @@ struct nft_set_ops {
 	int				(*insert)(const struct net *net,
 						  const struct nft_set *set,
 						  const struct nft_set_elem *elem,
-						  struct nft_set_ext **ext);
+						  void **priv);
 	void				(*activate)(const struct net *net,
 						    const struct nft_set *set,
 						    const struct nft_set_elem *elem);

net/netfilter/nf_tables_api.c +9 -6

index 96b0638c220a7..5238241c9a0b3 100644
@@ -6218,7 +6218,7 @@ EXPORT_SYMBOL_GPL(nft_set_catchall_lookup);
 static int nft_setelem_catchall_insert(const struct net *net,
 				       struct nft_set *set,
 				       const struct nft_set_elem *elem,
-				       struct nft_set_ext **pext)
+				       void **priv)
 {
 	struct nft_set_elem_catchall *catchall;
 	u8 genmask = nft_genmask_next(net);

@@ -6227,7 +6227,7 @@ static int nft_setelem_catchall_insert(const struct net *net,
 	list_for_each_entry(catchall, &set->catchall_list, list) {
 		ext = nft_set_elem_ext(set, catchall->elem);
 		if (nft_set_elem_active(ext, genmask)) {
-			*pext = ext;
+			*priv = catchall->elem;
 			return -EEXIST;
 		}
 	}

@@ -6245,14 +6245,15 @@ static int nft_setelem_catchall_insert(const struct net *net,
 static int nft_setelem_insert(const struct net *net,
 			      struct nft_set *set,
 			      const struct nft_set_elem *elem,
-			      struct nft_set_ext **ext, unsigned int flags)
+			      void **elem_priv,
+			      unsigned int flags)
 {
 	int ret;
 
 	if (flags & NFT_SET_ELEM_CATCHALL)
-		ret = nft_setelem_catchall_insert(net, set, elem, ext);
+		ret = nft_setelem_catchall_insert(net, set, elem, elem_priv);
 	else
-		ret = set->ops->insert(net, set, elem, ext);
+		ret = set->ops->insert(net, set, elem, elem_priv);
 
 	return ret;
 }

@@ -6420,6 +6421,7 @@ static int nft_add_set_elem(struct nft_ctx *ctx, struct nft_set *set,
 	enum nft_registers dreg;
 	struct nft_trans *trans;
 	bool set_full = false;
+	void *elem_priv;
 	u64 timeout;
 	u64 expiration;
 	int err, i;

@@ -6728,9 +6730,10 @@ static int nft_add_set_elem(struct nft_ctx *ctx, struct nft_set *set,
 
 	ext->genmask = nft_genmask_cur(ctx->net);
 
-	err = nft_setelem_insert(ctx->net, set, &elem, &ext2, flags);
+	err = nft_setelem_insert(ctx->net, set, &elem, &elem_priv, flags);
 	if (err) {
 		if (err == -EEXIST) {
+			ext2 = nft_set_elem_ext(set, elem_priv);
 			if (nft_set_ext_exists(ext, NFT_SET_EXT_DATA) ^
 			    nft_set_ext_exists(ext2, NFT_SET_EXT_DATA) ||
 			    nft_set_ext_exists(ext, NFT_SET_EXT_OBJREF) ^

net/netfilter/nft_set_bitmap.c +2 -2

index cbf7f7825f1b8..06b77100bef71 100644
@@ -123,7 +123,7 @@ static void *nft_bitmap_get(const struct net *net, const struct nft_set *set,
 
 static int nft_bitmap_insert(const struct net *net, const struct nft_set *set,
 			     const struct nft_set_elem *elem,
-			     struct nft_set_ext **ext)
+			     void **elem_priv)
 {
 	struct nft_bitmap *priv = nft_set_priv(set);
 	struct nft_bitmap_elem *new = elem->priv, *be;

@@ -132,7 +132,7 @@ static int nft_bitmap_insert(const struct net *net, const struct nft_set *set,
 
 	be = nft_bitmap_elem_find(set, new, genmask);
 	if (be) {
-		*ext = &be->ext;
+		*elem_priv = be;
 		return -EEXIST;
 	}

net/netfilter/nft_set_hash.c +4 -4

index 5a74ee4b7dfb3..60c0d72fb98b1 100644
@@ -168,7 +168,7 @@ static bool nft_rhash_update(struct nft_set *set, const u32 *key,
 
 static int nft_rhash_insert(const struct net *net, const struct nft_set *set,
 			    const struct nft_set_elem *elem,
-			    struct nft_set_ext **ext)
+			    void **elem_priv)
 {
 	struct nft_rhash *priv = nft_set_priv(set);
 	struct nft_rhash_elem *he = elem->priv;

@@ -185,7 +185,7 @@ static int nft_rhash_insert(const struct net *net, const struct nft_set *set,
 	if (IS_ERR(prev))
 		return PTR_ERR(prev);
 	if (prev) {
-		*ext = &prev->ext;
+		*elem_priv = prev;
 		return -EEXIST;
 	}
 	return 0;

@@ -588,7 +588,7 @@ static u32 nft_jhash(const struct nft_set *set, const struct nft_hash *priv,
 
 static int nft_hash_insert(const struct net *net, const struct nft_set *set,
 			   const struct nft_set_elem *elem,
-			   struct nft_set_ext **ext)
+			   void **elem_priv)
 {
 	struct nft_hash_elem *this = elem->priv, *he;
 	struct nft_hash *priv = nft_set_priv(set);

@@ -600,7 +600,7 @@ static int nft_hash_insert(const struct net *net, const struct nft_set *set,
 		if (!memcmp(nft_set_ext_key(&this->ext),
 			    nft_set_ext_key(&he->ext), set->klen) &&
 		    nft_set_elem_active(&he->ext, genmask)) {
-			*ext = &he->ext;
+			*elem_priv = he;
 			return -EEXIST;
 		}
 	}

net/netfilter/nft_set_pipapo.c +5 -5

index 4b37c6684bff6..c27ba1c5ae5da 100644
@@ -1260,13 +1260,13 @@ static struct nft_pipapo_match *pipapo_maybe_clone(const struct nft_set *set)
  * @net:	Network namespace
  * @set:	nftables API set representation
  * @elem:	nftables API element representation containing key data
- * @ext2:	Filled with pointer to &struct nft_set_ext in inserted element
+ * @elem_priv:	Filled with pointer to opaque set element
  *
  * Return: 0 on success, error pointer on failure.
  */
 static int nft_pipapo_insert(const struct net *net, const struct nft_set *set,
 			     const struct nft_set_elem *elem,
-			     struct nft_set_ext **ext2)
+			     void **elem_priv)
 {
 	const struct nft_set_ext *ext = nft_set_elem_ext(set, elem->priv);
 	union nft_pipapo_map_bucket rulemap[NFT_PIPAPO_MAX_FIELDS];

@@ -1301,7 +1301,7 @@ static int nft_pipapo_insert(const struct net *net, const struct nft_set *set,
 
 		if (!memcmp(start, dup_key->data, sizeof(*dup_key->data)) &&
 		    !memcmp(end, dup_end->data, sizeof(*dup_end->data))) {
-			*ext2 = &dup->ext;
+			*elem_priv = dup;
 			return -EEXIST;
 		}

@@ -1317,7 +1317,7 @@ static int nft_pipapo_insert(const struct net *net, const struct nft_set *set,
 	if (PTR_ERR(dup) != -ENOENT) {
 		if (IS_ERR(dup))
 			return PTR_ERR(dup);
-		*ext2 = &dup->ext;
+		*elem_priv = dup;
 		return -ENOTEMPTY;
 	}

@@ -1379,7 +1379,7 @@ static int nft_pipapo_insert(const struct net *net, const struct nft_set *set,
 		put_cpu_ptr(m->scratch);
 	}
 
-	*ext2 = &e->ext;
+	*elem_priv = e;
 
 	pipapo_map(m, rulemap, e);

net/netfilter/nft_set_rbtree.c +5 -5

index 433094c4200f9..e82e5cf107ee4 100644
@@ -319,7 +319,7 @@ static struct nft_rbtree_elem *nft_rbtree_prev_active(struct nft_rbtree_elem *rb
 
 static int __nft_rbtree_insert(const struct net *net, const struct nft_set *set,
 			       struct nft_rbtree_elem *new,
-			       struct nft_set_ext **ext)
+			       void **elem_priv)
 {
 	struct nft_rbtree_elem *rbe, *rbe_le = NULL, *rbe_ge = NULL, *rbe_prev;
 	struct rb_node *node, *next, *parent, **p, *first = NULL;

@@ -437,7 +437,7 @@ static int __nft_rbtree_insert(const struct net *net, const struct nft_set *set,
 	 */
 	if (rbe_ge && !nft_rbtree_cmp(set, new, rbe_ge) &&
 	    nft_rbtree_interval_start(rbe_ge) == nft_rbtree_interval_start(new)) {
-		*ext = &rbe_ge->ext;
+		*elem_priv = rbe_ge;
 		return -EEXIST;
 	}

@@ -446,7 +446,7 @@ static int __nft_rbtree_insert(const struct net *net, const struct nft_set *set,
 	 */
 	if (rbe_le && !nft_rbtree_cmp(set, new, rbe_le) &&
 	    nft_rbtree_interval_end(rbe_le) == nft_rbtree_interval_end(new)) {
-		*ext = &rbe_le->ext;
+		*elem_priv = rbe_le;
 		return -EEXIST;
 	}

@@ -506,7 +506,7 @@ static int __nft_rbtree_insert(const struct net *net, const struct nft_set *set,
 
 static int nft_rbtree_insert(const struct net *net, const struct nft_set *set,
 			     const struct nft_set_elem *elem,
-			     struct nft_set_ext **ext)
+			     void **elem_priv)
 {
 	struct nft_rbtree *priv = nft_set_priv(set);
 	struct nft_rbtree_elem *rbe = elem->priv;

@@ -520,7 +520,7 @@ static int nft_rbtree_insert(const struct net *net, const struct nft_set *set,
 
 		write_lock_bh(&priv->lock);
 		write_seqcount_begin(&priv->count);
-		err = __nft_rbtree_insert(net, set, rbe, ext);
+		err = __nft_rbtree_insert(net, set, rbe, elem_priv);
 		write_seqcount_end(&priv->count);
 		write_unlock_bh(&priv->lock);
 	} while (err == -EAGAIN);

Signature · 1 line

2.53.0

Sasha Levin

maintainer

2026-09-30 14:05 UTC #2 lore raw

PATCH 2/2 netfilter: nf_tables: skip expired catchall elements on insert and delete

From: Aohan Mei <[email protected]>

[ Upstream commit 70194dc37670bd08e44b471389861cc01bd3a3c9 ]

nft_setelem_catchall_insert() looks up duplicates with nft_set_elem_active() only, while nft_set_catchall_lookup() and the dump path additionally skip expired elements.

Reported-by TencentOS Corvus AI <[email protected]>

Cc [email protected]

Fixes aaa31047a6d2 ("netfilter: nftables: add catch-all set element support")

Assisted-by CodeBuddy:Kimi-K3

Signed-off-by Aohan Mei <[email protected]>

Signed-off-by Pablo Neira Ayuso <[email protected]>

Signed-off-by Sasha Levin <[email protected]>

---
 net/netfilter/nf_tables_api.c | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

net/netfilter/nf_tables_api.c +8 -2

index 5238241c9a0b3..b64f25ef13dd7 100644
@@ -6222,11 +6222,14 @@ static int nft_setelem_catchall_insert(const struct net *net,
 {
 	struct nft_set_elem_catchall *catchall;
 	u8 genmask = nft_genmask_next(net);
+	u64 tstamp = nft_net_tstamp(net);
 	struct nft_set_ext *ext;
 
 	list_for_each_entry(catchall, &set->catchall_list, list) {
 		ext = nft_set_elem_ext(set, catchall->elem);
-		if (nft_set_elem_active(ext, genmask)) {
+		if (nft_set_elem_active(ext, genmask) &&
+		    !__nft_set_elem_expired(ext, tstamp) &&
+		    !nft_set_elem_is_dead(ext)) {
 			*priv = catchall->elem;
 			return -EEXIST;
 		}

@@ -6287,11 +6290,14 @@ static int nft_setelem_catchall_deactivate(const struct net *net,
 					   struct nft_set_elem *elem)
 {
 	struct nft_set_elem_catchall *catchall;
+	u64 tstamp = nft_net_tstamp(net);
 	struct nft_set_ext *ext;
 
 	list_for_each_entry(catchall, &set->catchall_list, list) {
 		ext = nft_set_elem_ext(set, catchall->elem);
-		if (!nft_is_active_next(net, ext))
+		if (!nft_is_active_next(net, ext) ||
+		    __nft_set_elem_expired(ext, tstamp) ||
+		    nft_set_elem_is_dead(ext))
 			continue;
 
 		kfree(elem->priv);

Signature · 1 line

2.53.0