From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from Chamillionaire.breakpoint.cc (Chamillionaire.breakpoint.cc [91.216.245.30]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id B8A7870815 for ; Fri, 25 Oct 2024 13:54:53 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=91.216.245.30 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1729864495; cv=none; b=kbQPA08Mf2syDxQnGyD1970XelE2rAgmRKjI4MEIBf1BY+zqYMqXtpVmYAz+sJlXWFfXfM9tvbOaTM4FMMSgA7yJbeOxn/Q+5CQXaKOqXOtGHPQJieMJblrEO4CxK/1i2+CGmZNnOIPFEVdRLxqZUztyStVIAIkuxM4t1brVFqc= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1729864495; c=relaxed/simple; bh=fw9nbwoVJJhlV25zBt9TaQwmVijRcGYBDYQCxUinK6o=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=bLLQnPqAN2GFG4ZuC3w29dEp/yGjVH/8RYrnRM7kTetBSPJ3WF2TXQksuGHFgl1YNnGxFna7U019AVZ7bZrqJkvv4AhjLOJaf0BTpC59rFsCsnrhaq2bmIUvSVXkWkz8QbwQ3Ng/u6MbJ3xJ1qVFn2isxhN3VBELbvAx64egIm8= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=strlen.de; spf=pass smtp.mailfrom=breakpoint.cc; arc=none smtp.client-ip=91.216.245.30 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=strlen.de Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=breakpoint.cc Received: from fw by Chamillionaire.breakpoint.cc with local (Exim 4.92) (envelope-from ) id 1t4KmC-0005zJ-9u; Fri, 25 Oct 2024 15:54:52 +0200 From: Florian Westphal To: Cc: Florian Westphal Subject: [PATCH nf-next 7/7] netfilter: nf_tables: must hold rcu read lock while iterating object type list Date: Fri, 25 Oct 2024 15:32:24 +0200 Message-ID: <20241025133230.22491-8-fw@strlen.de> X-Mailer: git-send-email 2.45.2 In-Reply-To: <20241025133230.22491-1-fw@strlen.de> References: <20241025133230.22491-1-fw@strlen.de> Precedence: bulk X-Mailing-List: netfilter-devel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 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. Fixes: dad3bdeef45f ("netfilter: nf_tables: fix memory leak during stateful obj update"). Signed-off-by: Florian Westphal --- 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 3db4457f46a2..7712201ecf2a 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(!type)) + return -ENOENT; + 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); } -- 2.45.2