From: Florian Westphal fw@strlen.de
stable inclusion from stable-v5.10.103 commit 7e9880e81d3fd6a43c202f205717485290432826 bugzilla: https://gitee.com/openeuler/kernel/issues/I56NE7
Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=...
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commit dad3bdeef45f81a6e90204bcc85360bb76eccec7 upstream.
stateful objects can be updated from the control plane. The transaction logic allocates a temporary object for this purpose.
The ->init function was called for this object, so plain kfree() leaks resources. We must call ->destroy function of the object.
nft_obj_destroy does this, but it also decrements the module refcount, but the update path doesn't increment it.
To avoid special-casing the update object release, do module_get for the update case too and release it via nft_obj_destroy().
Fixes: d62d0ba97b58 ("netfilter: nf_tables: Introduce stateful object update operation") Cc: Fernando Fernandez Mancera ffmancera@riseup.net Signed-off-by: Florian Westphal fw@strlen.de Signed-off-by: Pablo Neira Ayuso pablo@netfilter.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org Signed-off-by: Yu Liao liaoyu15@huawei.com Reviewed-by: Wei Li liwei391@huawei.com Signed-off-by: Zheng Zengkai zhengzengkai@huawei.com --- net/netfilter/nf_tables_api.c | 13 +++++++++---- 1 file changed, 9 insertions(+), 4 deletions(-)
diff --git a/net/netfilter/nf_tables_api.c b/net/netfilter/nf_tables_api.c index b781ba97c474..fdd1da9ecea9 100644 --- a/net/netfilter/nf_tables_api.c +++ b/net/netfilter/nf_tables_api.c @@ -5924,12 +5924,15 @@ static int nf_tables_updobj(const struct nft_ctx *ctx, { struct nft_object *newobj; struct nft_trans *trans; - int err; + int err = -ENOMEM; + + if (!try_module_get(type->owner)) + return -ENOENT;
trans = nft_trans_alloc(ctx, NFT_MSG_NEWOBJ, sizeof(struct nft_trans_obj)); if (!trans) - return -ENOMEM; + goto err_trans;
newobj = nft_obj_init(ctx, type, attr); if (IS_ERR(newobj)) { @@ -5946,6 +5949,8 @@ static int nf_tables_updobj(const struct nft_ctx *ctx,
err_free_trans: kfree(trans); +err_trans: + module_put(type->owner); return err; }
@@ -7555,7 +7560,7 @@ static void nft_obj_commit_update(struct nft_trans *trans) if (obj->ops->update) obj->ops->update(obj, newobj);
- kfree(newobj); + nft_obj_destroy(&trans->ctx, newobj); }
static void nft_commit_release(struct nft_trans *trans) @@ -8202,7 +8207,7 @@ static int __nf_tables_abort(struct net *net, enum nfnl_abort_action action) break; case NFT_MSG_NEWOBJ: if (nft_trans_obj_update(trans)) { - kfree(nft_trans_obj_newobj(trans)); + nft_obj_destroy(&trans->ctx, nft_trans_obj_newobj(trans)); nft_trans_destroy(trans); } else { trans->ctx.table->use--;