Subject: [PATCH net 4/5] netfilter: nft_connlimit: memleak if nf_ct_netns_get() fails

From: Pablo Neira Ayuso <[email-masked]>
Date: Thu, 20 Jan 2022 13:52:11 +0100

Check if nf_ct_netns_get() fails then release the limit object
previously allocated via kmalloc().

Fixes: 37f319f37d90 ("netfilter: nft_connlimit: move stateful fields out of expression data")
Signed-off-by: Pablo Neira Ayuso <[email-masked]>
---
 net/netfilter/nft_connlimit.c | 11 ++++++++++-
 1 file changed, 10 insertions(+), 1 deletion(-)

diff --git a/net/netfilter/nft_connlimit.c b/net/netfilter/nft_connlimit.c
index 7d00a1452b1d..3362417ebfdb 100644
--- a/net/netfilter/nft_connlimit.c
+++ b/net/netfilter/nft_connlimit.c
@@ -62,6 +62,7 @@ static int nft_connlimit_do_init(const struct nft_ctx *ctx,
 {
 	bool invert = false;
 	u32 flags, limit;
+	int err;
 
 	if (!tb[NFTA_CONNLIMIT_COUNT])
 		return -EINVAL;
@@ -84,7 +85,15 @@ static int nft_connlimit_do_init(const struct nft_ctx *ctx,
 	priv->limit	= limit;
 	priv->invert	= invert;
 
-	return nf_ct_netns_get(ctx->net, ctx->family);
+	err = nf_ct_netns_get(ctx->net, ctx->family);
+	if (err < 0)
+		goto err_netns;
+
+	return 0;
+err_netns:
+	kfree(priv->list);
+
+	return err;
 }
 
 static void nft_connlimit_do_destroy(const struct nft_ctx *ctx,
-- 
2.30.2