netfilter: nf_tables: fix unexpected EOPNOTSUPP error

If the object type doesn't implement an update operation and the user tries to
update it will silently ignore the update operation.

Fixes: aa4095a156b5 ("netfilter: nf_tables: fix possible null-pointer dereference in object update")
Signed-off-by: Fernando Fernandez Mancera <ffmancera@riseup.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

1 files changed, 2 insertions, 4 deletions

diff --git a/net/netfilter/nf_tables_api.c b/net/netfilter/nf_tables_api.c
index d481f9baca2f..aa26841ad9a1 100644
--- a/net/netfilter/nf_tables_api.c
+++ b/net/netfilter/nf_tables_api.c
@@ -5143,9 +5143,6 @@ static int nf_tables_updobj(const struct nft_ctx *ctx,
         struct nft_trans *trans;
         int err;
 
-        if (!obj->ops->update)
-                return -EOPNOTSUPP;
-
         trans = nft_trans_alloc(ctx, NFT_MSG_NEWOBJ,
                                 sizeof(struct nft_trans_obj));
         if (!trans)
@@ -6499,7 +6496,8 @@ static void nft_obj_commit_update(struct nft_trans *trans)
         obj = nft_trans_obj(trans);
         newobj = nft_trans_obj_newobj(trans);
 
-        obj->ops->update(obj, newobj);
+        if (obj->ops->update)
+                obj->ops->update(obj, newobj);
 
         kfree(newobj);
 }