[PATCH 5.10.y 2/7] netfilter: nft_set_pipapo: make pipapo_clone helper return NULL

[Sasha Levin <sashal@kernel.org>]

From: Florian Westphal <fw@strlen.de>

[ Upstream commit 80efd2997fb9343a0283cf3cac5524a4595c8ff4 ]

Currently it returns an error pointer, but the only possible failure
is ENOMEM.

After a followup patch, we'd need to discard the errno code, i.e.

x = pipapo_clone()
if (IS_ERR(x))
	return NULL

or make more changes to fix up callers to expect IS_ERR() code
from set->ops->deactivate().

So simplify this and make it return ptr-or-null.

Signed-off-by: Florian Westphal <fw@strlen.de>
Reviewed-by: Stefano Brivio <sbrivio@redhat.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Stable-dep-of: 47e65eff5069 ("netfilter: nft_set_pipapo: don't leak bad clone into future transaction")
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 net/netfilter/nft_set_pipapo.c | 14 +++++++-------
 1 file changed, 7 insertions(+), 7 deletions(-)

diff --git a/net/netfilter/nft_set_pipapo.c b/net/netfilter/nft_set_pipapo.c
index a01905381b5365..5f2885a878dda7 100644
--- a/net/netfilter/nft_set_pipapo.c
+++ b/net/netfilter/nft_set_pipapo.c
@@ -1318,7 +1318,7 @@ static int nft_pipapo_insert(const struct net *net, const struct nft_set *set,
  * pipapo_clone() - Clone matching data to create new working copy
  * @old:	Existing matching data
  *
- * Return: copy of matching data passed as 'old', error pointer on failure
+ * Return: copy of matching data passed as 'old' or NULL.
  */
 static struct nft_pipapo_match *pipapo_clone(struct nft_pipapo_match *old)
 {
@@ -1329,7 +1329,7 @@ static struct nft_pipapo_match *pipapo_clone(struct nft_pipapo_match *old)
 	new = kmalloc(sizeof(*new) + sizeof(*dst) * old->field_count,
 		      GFP_KERNEL);
 	if (!new)
-		return ERR_PTR(-ENOMEM);
+		return NULL;
 
 	new->field_count = old->field_count;
 	new->bsize_max = old->bsize_max;
@@ -1403,7 +1403,7 @@ static struct nft_pipapo_match *pipapo_clone(struct nft_pipapo_match *old)
 	free_percpu(new->scratch);
 	kfree(new);
 
-	return ERR_PTR(-ENOMEM);
+	return NULL;
 }
 
 /**
@@ -1743,7 +1743,7 @@ static void nft_pipapo_commit(const struct nft_set *set)
 		goto out;
 
 	new_clone = pipapo_clone(priv->clone);
-	if (IS_ERR(new_clone))
+	if (!new_clone)
 		goto out;
 
 	priv->dirty = false;
@@ -1769,7 +1769,7 @@ static void nft_pipapo_abort(const struct nft_set *set)
 	m = rcu_dereference(priv->match);
 
 	new_clone = pipapo_clone(m);
-	if (IS_ERR(new_clone))
+	if (!new_clone)
 		return;
 
 	priv->dirty = false;
@@ -2214,8 +2214,8 @@ static int nft_pipapo_init(const struct nft_set *set,
 
 	/* Create an initial clone of matching data for next insertion */
 	priv->clone = pipapo_clone(m);
-	if (IS_ERR(priv->clone)) {
-		err = PTR_ERR(priv->clone);
+	if (!priv->clone) {
+		err = -ENOMEM;
 		goto out_free;
 	}
 
-- 
2.53.0