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 59D322309B0; Mon, 10 Mar 2025 18:13:58 +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=1741630438; cv=none; b=ODc2fD/JQ8ZJH/NIy8GXlqBFkwb3rAiKmYRY+ijkMr1AqLbOwDBQQPeLyrg/rhO3CRYu99CvGNBzbDwbT1dnglX/7oIcLDSORhw//YnpiEJqKTNdvKTMG4rAzyLc/pw6FX3NbxZn+AWHG59Wrr9WvRh7YtpTJf89u9IRLPqmo9Y= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1741630438; c=relaxed/simple; bh=IqTOiPQNJet0PxWXYP/qP93RqL0Ncg8bNMt/b4XNfiw=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=lKdhO5fQtWA5VqouJ0e5fY3h3aaTmIuA8FbkTf8dhLB36VSvUdktLrEaTqSVeuXLzw2bslrv0jAq7/ynhMHYrYRxZqZD76ZAoPvd9cadA7fVITsi/nekfl2POi5r5I2nvUHdbiJCLgG5f0ya1gUytB9eKERCRtPKA0plwq/KU5A= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=yv5S+iu1; 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="yv5S+iu1" Received: by smtp.kernel.org (Postfix) with ESMTPSA id CBB22C4CEE5; Mon, 10 Mar 2025 18:13:57 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1741630438; bh=IqTOiPQNJet0PxWXYP/qP93RqL0Ncg8bNMt/b4XNfiw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=yv5S+iu1QgpxHSAbCyv0pBBz2LUaatXsoUnoi7hrSWvFULCynL5IsqtWAuzyROcsP zp4Y29l0DxPmnFMf1VP7mdy8lF0LEhF+9EkYI7ybiCiHnaNjqIud9Oj3NJFPeoFdVn Rdpv60jqkGC5cd80sZVv+Cd6SC3hgL0RoUbm2WtQ= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Eric Dumazet , David Ahern , Kuniyuki Iwashima , Jakub Kicinski , Sasha Levin Subject: [PATCH 5.15 406/620] arp: use RCU protection in arp_xmit() Date: Mon, 10 Mar 2025 18:04:12 +0100 Message-ID: <20250310170601.616924205@linuxfoundation.org> X-Mailer: git-send-email 2.48.1 In-Reply-To: <20250310170545.553361750@linuxfoundation.org> References: <20250310170545.553361750@linuxfoundation.org> User-Agent: quilt/0.68 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: Eric Dumazet [ Upstream commit a42b69f692165ec39db42d595f4f65a4c8f42e44 ] arp_xmit() can be called without RTNL or RCU protection. Use RCU protection to avoid potential UAF. Fixes: 29a26a568038 ("netfilter: Pass struct net into the netfilter hooks") Signed-off-by: Eric Dumazet Reviewed-by: David Ahern Reviewed-by: Kuniyuki Iwashima Link: https://patch.msgid.link/20250207135841.1948589-5-edumazet@google.com Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin --- net/ipv4/arp.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/net/ipv4/arp.c b/net/ipv4/arp.c index 8ae9bd6f91c19..6879e0b70c769 100644 --- a/net/ipv4/arp.c +++ b/net/ipv4/arp.c @@ -637,10 +637,12 @@ static int arp_xmit_finish(struct net *net, struct sock *sk, struct sk_buff *skb */ void arp_xmit(struct sk_buff *skb) { + rcu_read_lock(); /* Send it off, maybe filter it using firewalling first. */ NF_HOOK(NFPROTO_ARP, NF_ARP_OUT, - dev_net(skb->dev), NULL, skb, NULL, skb->dev, + dev_net_rcu(skb->dev), NULL, skb, NULL, skb->dev, arp_xmit_finish); + rcu_read_unlock(); } EXPORT_SYMBOL(arp_xmit); -- 2.39.5