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 D50521D63E8; Wed, 19 Feb 2025 09:03:37 +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=1739955817; cv=none; b=dUjxoR41eNHcBG62Wap3SvSn1EK6fKjeyE50MdEnZxFDRzMxbwn41p/97cL0mz9D6OSbtOLU4BaqmUQZNg8+3BudwaKf6U7JAvUAlpqfe+4HoYgjH6OHsKoanDNCk+CpFWda4Zn02uJQpU2FT/qe2bND7arbftbNZPQRUGgHniY= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1739955817; c=relaxed/simple; bh=9JcsFF4UatNFKJuIICrRgV4GyAku7KCKY3fOF+japdw=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=mYcPT6beJCVGX1QegBNf967053mIaHL+yQR+7P7oFatpWeyPFh92Aj3z+8saYh3+ZCTobEv9ryFiUkKtPRIe9qXRUmdqvvoyAzx/CNmmsmRd7OAk6RYD4KhkvivpAx7mbZqKFMsPknNU6vKkZpT2HczwnaPZv2lyafhyh1OU/sU= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=cxci0NyG; 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="cxci0NyG" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 57744C4CEE6; Wed, 19 Feb 2025 09:03:37 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1739955817; bh=9JcsFF4UatNFKJuIICrRgV4GyAku7KCKY3fOF+japdw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=cxci0NyG7a0OD2QMEQtVW07gEgOMNSMKOu0qtbw1IPicf/s1do8pEegd6prj7ZAkh am3T8NcJrezL4fgZ0FDYDxM8XXC3aWKZVrmkSngqMcKlh+eGIvsC56K1/USCgSmTD1 fnr0Y7TBElGH7gJieTOKBtk8pakRc2Bks+dNyGmU= 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 6.6 123/152] neighbour: use RCU protection in __neigh_notify() Date: Wed, 19 Feb 2025 09:28:56 +0100 Message-ID: <20250219082554.918054462@linuxfoundation.org> X-Mailer: git-send-email 2.48.1 In-Reply-To: <20250219082550.014812078@linuxfoundation.org> References: <20250219082550.014812078@linuxfoundation.org> User-Agent: quilt/0.68 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.6-stable review patch. If anyone has any objections, please let me know. ------------------ From: Eric Dumazet [ Upstream commit becbd5850c03ed33b232083dd66c6e38c0c0e569 ] __neigh_notify() can be called without RTNL or RCU protection. Use RCU protection to avoid potential UAF. Fixes: 426b5303eb43 ("[NETNS]: Modify the neighbour table code so it handles multiple network namespaces") Signed-off-by: Eric Dumazet Reviewed-by: David Ahern Reviewed-by: Kuniyuki Iwashima Link: https://patch.msgid.link/20250207135841.1948589-4-edumazet@google.com Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin --- net/core/neighbour.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/net/core/neighbour.c b/net/core/neighbour.c index 118d932b3baa1..e44feb39d459a 100644 --- a/net/core/neighbour.c +++ b/net/core/neighbour.c @@ -3508,10 +3508,12 @@ static const struct seq_operations neigh_stat_seq_ops = { static void __neigh_notify(struct neighbour *n, int type, int flags, u32 pid) { - struct net *net = dev_net(n->dev); struct sk_buff *skb; int err = -ENOBUFS; + struct net *net; + rcu_read_lock(); + net = dev_net_rcu(n->dev); skb = nlmsg_new(neigh_nlmsg_size(), GFP_ATOMIC); if (skb == NULL) goto errout; @@ -3524,9 +3526,11 @@ static void __neigh_notify(struct neighbour *n, int type, int flags, goto errout; } rtnl_notify(skb, net, 0, RTNLGRP_NEIGH, NULL, GFP_ATOMIC); - return; + goto out; errout: rtnl_set_sk_err(net, RTNLGRP_NEIGH, err); +out: + rcu_read_unlock(); } void neigh_app_ns(struct neighbour *n) -- 2.39.5