[PATCH] netfilter: nf_tables: fix memory leak on error exit return

[Colin King]

From: Colin Ian King <colin.k...@canonical.com>

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.k...@canonical.com>
---
 net/netfilter/nf_tables_api.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/net/netfilter/nf_tables_api.c b/net/netfilter/nf_tables_api.c
index 6422eba367cf..a3d77aa0f752 100644
--- a/net/netfilter/nf_tables_api.c
+++ b/net/netfilter/nf_tables_api.c
@@ -4098,8 +4098,10 @@ 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),
-- 
2.17.0