From patchwork Wed Nov 6 23:46:25 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Pablo Neira Ayuso X-Patchwork-Id: 13865644 X-Patchwork-Delegate: kuba@kernel.org Received: from mail.netfilter.org (mail.netfilter.org [217.70.188.207]) by smtp.subspace.kernel.org (Postfix) with ESMTP id AF1D820EA38; Wed, 6 Nov 2024 23:46:45 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=217.70.188.207 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1730936807; cv=none; b=huVdqupgF3U/VO0Jc2qc8zeEd2YTV2K0WIy/BN526b/aEVWxseTvxQRMQkxDrrKtl7tvZR5jKZ72up2xmSGgxi66D0DRwQ3oI6tItrKAviHup1GhFVN3MjEs9vJE4AbR98B4rYHZkHbah+SS03evbbmM/cUgCgfIcB9K2Yy7YSM= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1730936807; c=relaxed/simple; bh=vSRNT4hnRNjOvax/2yhMZp64EHIcsvTri/wD0aFNVTg=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=O+IKMmVraHKxus1rxtKZZFreCKdzthhhZoLmEMY8ZaMEXbHffEsR7WLMzQ8wrh0LGt3WapTdvOjbJB9aC54joCeLSbZ8zQCBCui45JSQpFr28ceXShS99X/qS9x9n8dV0gg+cUKp2kdvHLGDymlwBbq70js6aYXJkEPry9LmsBQ= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=netfilter.org; spf=pass smtp.mailfrom=netfilter.org; arc=none smtp.client-ip=217.70.188.207 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=netfilter.org Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=netfilter.org From: Pablo Neira Ayuso To: netfilter-devel@vger.kernel.org Cc: davem@davemloft.net, netdev@vger.kernel.org, kuba@kernel.org, pabeni@redhat.com, edumazet@google.com, fw@strlen.de Subject: [PATCH net-next 11/11] netfilter: nf_tables: must hold rcu read lock while iterating object type list Date: Thu, 7 Nov 2024 00:46:25 +0100 Message-Id: <20241106234625.168468-12-pablo@netfilter.org> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20241106234625.168468-1-pablo@netfilter.org> References: <20241106234625.168468-1-pablo@netfilter.org> Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Patchwork-Delegate: kuba@kernel.org From: Florian Westphal Update of stateful object triggers: WARNING: suspicious RCU usage net/netfilter/nf_tables_api.c:7759 RCU-list traversed in non-reader section!! other info that might help us debug this: rcu_scheduler_active = 2, debug_locks = 1 1 lock held by nft/3060: #0: ffff88810f0578c8 (&nft_net->commit_mutex){+.+.}-{4:4}, [..] ... but this list is not protected by the transaction mutex but the nfnl nftables subsystem mutex. Switch to nft_obj_type_get which will acquire rcu read lock, bump refcount, and returns the result. v3: Dan Carpenter points out nft_obj_type_get returns error pointer, not NULL, on error. Fixes: dad3bdeef45f ("netfilter: nf_tables: fix memory leak during stateful obj update"). Signed-off-by: Florian Westphal Signed-off-by: Pablo Neira Ayuso --- net/netfilter/nf_tables_api.c | 13 ++++++------- 1 file changed, 6 insertions(+), 7 deletions(-) diff --git a/net/netfilter/nf_tables_api.c b/net/netfilter/nf_tables_api.c index de8e48a5c62d..b7a817e483aa 100644 --- a/net/netfilter/nf_tables_api.c +++ b/net/netfilter/nf_tables_api.c @@ -7809,9 +7809,7 @@ static int nf_tables_updobj(const struct nft_ctx *ctx, struct nft_trans *trans; int err = -ENOMEM; - if (!try_module_get(type->owner)) - return -ENOENT; - + /* caller must have obtained type->owner reference. */ trans = nft_trans_alloc(ctx, NFT_MSG_NEWOBJ, sizeof(struct nft_trans_obj)); if (!trans) @@ -7879,15 +7877,16 @@ static int nf_tables_newobj(struct sk_buff *skb, const struct nfnl_info *info, if (info->nlh->nlmsg_flags & NLM_F_REPLACE) return -EOPNOTSUPP; - type = __nft_obj_type_get(objtype, family); - if (WARN_ON_ONCE(!type)) - return -ENOENT; - if (!obj->ops->update) return 0; + type = nft_obj_type_get(net, objtype, family); + if (WARN_ON_ONCE(IS_ERR(type))) + return PTR_ERR(type); + nft_ctx_init(&ctx, net, skb, info->nlh, family, table, NULL, nla); + /* type->owner reference is put when transaction object is released. */ return nf_tables_updobj(&ctx, type, nla[NFTA_OBJ_DATA], obj); }