netfilter: nf_tables: fix memory leak on error exit return

Currently the -EBUSY error return path is not free'ing resources
allocated earlier, leaving a memory leak. Fix this by exiting via the
error exit label err5 that performs the necessary resource clean
up.

Detected by CoverityScan, CID#1432975 ("Resource leak")

Fixes: 9744a6fcefcb ("netfilter: nf_tables: check if same extensions are set when adding elements")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

diff --git a/net/netfilter/nf_tables_api.c b/net/netfilter/nf_tables_api.c
index 3806db3..91e80aa 100644 (file)
--- a/net/netfilter/nf_tables_api.c
+++ b/net/netfilter/nf_tables_api.c
@@ -4080,8 +4080,10 @@ static int nft_add_set_elem(struct nft_ctx *ctx, struct nft_set *set,
                        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) ^
-                           nft_set_ext_exists(ext2, NFT_SET_EXT_OBJREF))
-                               return -EBUSY;
+                           nft_set_ext_exists(ext2, NFT_SET_EXT_OBJREF)) {
+                               err = -EBUSY;
+                               goto err5;
+                       }
                        if ((nft_set_ext_exists(ext, NFT_SET_EXT_DATA) &&
                             nft_set_ext_exists(ext2, NFT_SET_EXT_DATA) &&
                             memcmp(nft_set_ext_data(ext),