netfilter: nf_tables: check if same extensions are set when adding elements
If no NLM_F_EXCL is set and the element already exists in the set, make
sure that both elements have the same extensions.
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 434c739..11a96e8 100644
--- a/net/netfilter/nf_tables_api.c
+++ b/net/netfilter/nf_tables_api.c
@@ -3749,6 +3749,11 @@
err = set->ops->insert(ctx->net, set, &elem, &ext2);
if (err) {
if (err == -EEXIST) {
+ 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;
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),