From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 A29217D074; Mon, 8 Apr 2024 14:03:48 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1712585028; cv=none; b=ZjuKP7Uj77gSsyOADX9ZfD4Uh66gXblk1e7TSO6HMB5tQ2ThjZO9u/hLrRGj54WG5yNfy81JHBS2pUKD6ItKrjmtP6lFjqw1OodU/mtTTImfcZq0K80zIkhtXEZXv5GQNGzV00XImThCDmvEctmgq5Lc3+ATsspJWxqVLzoiwK0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1712585028; c=relaxed/simple; bh=JWwKCml/gfwENVLIv0pKhMKCvJaDyPxnxggBftA9qvQ=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=nDcM/QMENMKvBoi2pyQLc23NDo2U9bmUX56M5RCzcDpaIDebxWL6k4EGcsMo2j1o3msk3bDpEs62+b04hkv2hLwQ2VI3j2hY8GMy/sx1peFu5zuItBs4PBFl6Ghakn5QOPagicqSnx8Xso0uH4pZu6ZwDSdgnyxGIL2dyL0prGM= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=xnfKFrTR; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="xnfKFrTR" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 2AEB9C433C7; Mon, 8 Apr 2024 14:03:47 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1712585028; bh=JWwKCml/gfwENVLIv0pKhMKCvJaDyPxnxggBftA9qvQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=xnfKFrTRkYWI9+Fjm9H9mpkOHKZUWuZ+uHcgyLRxbIZcah02s2EHo0WsdmrJsWLQ6 SRQTmCPzl66V0/FJMrBQkg2+SwoGghOH2xvpEGfVyNarOLAdWRJze3dGAErdTki/sO BWQsdisd0TakwwqoZcxgT04c9UOcCDgoHHzD5VWQ= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Ziyang Xuan , Pablo Neira Ayuso Subject: [PATCH 5.15 638/690] netfilter: nf_tables: Fix potential data-race in __nft_flowtable_type_get() Date: Mon, 8 Apr 2024 14:58:24 +0200 Message-ID: <20240408125422.782282732@linuxfoundation.org> X-Mailer: git-send-email 2.44.0 In-Reply-To: <20240408125359.506372836@linuxfoundation.org> References: <20240408125359.506372836@linuxfoundation.org> User-Agent: quilt/0.67 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 5.15-stable review patch. If anyone has any objections, please let me know. ------------------ From: Ziyang Xuan commit 24225011d81b471acc0e1e315b7d9905459a6304 upstream. nft_unregister_flowtable_type() within nf_flow_inet_module_exit() can concurrent with __nft_flowtable_type_get() within nf_tables_newflowtable(). And thhere is not any protection when iterate over nf_tables_flowtables list in __nft_flowtable_type_get(). Therefore, there is pertential data-race of nf_tables_flowtables list entry. Use list_for_each_entry_rcu() to iterate over nf_tables_flowtables list in __nft_flowtable_type_get(), and use rcu_read_lock() in the caller nft_flowtable_type_get() to protect the entire type query process. Fixes: 3b49e2e94e6e ("netfilter: nf_tables: add flow table netlink frontend") Signed-off-by: Ziyang Xuan Signed-off-by: Pablo Neira Ayuso Signed-off-by: Greg Kroah-Hartman --- net/netfilter/nf_tables_api.c | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-) --- a/net/netfilter/nf_tables_api.c +++ b/net/netfilter/nf_tables_api.c @@ -7693,11 +7693,12 @@ static int nft_flowtable_parse_hook(cons return err; } +/* call under rcu_read_lock */ static const struct nf_flowtable_type *__nft_flowtable_type_get(u8 family) { const struct nf_flowtable_type *type; - list_for_each_entry(type, &nf_tables_flowtables, list) { + list_for_each_entry_rcu(type, &nf_tables_flowtables, list) { if (family == type->family) return type; } @@ -7709,9 +7710,13 @@ nft_flowtable_type_get(struct net *net, { const struct nf_flowtable_type *type; + rcu_read_lock(); type = __nft_flowtable_type_get(family); - if (type != NULL && try_module_get(type->owner)) + if (type != NULL && try_module_get(type->owner)) { + rcu_read_unlock(); return type; + } + rcu_read_unlock(); lockdep_nfnl_nft_mutex_not_held(); #ifdef CONFIG_MODULES