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 AD64D1BA089; Mon, 17 Jun 2024 13:27:51 +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=1718630871; cv=none; b=qrEFkP/J34lGXHg+DKwsQYFrw0gvOCH+ljTOv1hd8mrGVKJO8PLghw7t2Y8doI42sU+t+CDJZfs6UhUJZUplLKmokWlVJ6l5oQrFnxJUW4NRYDyr0TtG70QkoO/k4qQ/UyL+XjXpxprZOjSCdmRcTZD7jdloG3d/EOrT5QIzuBA= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1718630871; c=relaxed/simple; bh=zo7vGdQmD/9WW6TxmkLYuuXaSiAwi6gfF0+dfbpj6Xo=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=EcLlXmpkRgHq8a7Ii2lBKL+PSzAreaEeHLQNYXqjnMfpBleCxAlBZMyKorvh/dUXibrFqzhYKVJbcQGPEw7+OctWmfEbuLwO0FI92RqyPfWFnXkV4ktmuZ5sZRfqXB7WacPsKGOZLliOJJRRQbiRMuSLIfR/2VNkGjcDPIJkrew= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=ts7W/raA; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="ts7W/raA" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 926D0C4AF1C; Mon, 17 Jun 2024 13:27:50 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1718630871; bh=zo7vGdQmD/9WW6TxmkLYuuXaSiAwi6gfF0+dfbpj6Xo=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=ts7W/raALrA6pYoxS0Fl52M6QGrrEgNhizmAghxyFv03d+ab5cksf3+8mI2ESbxi/ RiU25e7heNWRQtshkIUZxC6z2NKYgWc8xQzUI5kc1SSwFkEEa0AZtOvfgPwwOGkFyV S74uY63E8vmp3dNjofQLjFOJRqQqalA4wFK002QizFKjmvhW38SDNbJxWb5fGLcZlD ex78/a7FqSxKzfcEMagB5CIQDTzPwBLOegJz2/QmxqOzQMlx9kMaOWjnL26u3u82+5 XU1r7E04Fb+o6jqTX7BlNKEBA86NCEl2YtQZsrRfRQPyowDvCWdULAN3UyrqHN/FEP EDaHWY+ldPpKw== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Eric Dumazet , Paolo Abeni , Jakub Kicinski , Sasha Levin , davem@davemloft.net, dsahern@kernel.org, netdev@vger.kernel.org Subject: [PATCH AUTOSEL 5.4 7/9] ila: block BH in ila_output() Date: Mon, 17 Jun 2024 09:27:34 -0400 Message-ID: <20240617132739.2590390-7-sashal@kernel.org> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20240617132739.2590390-1-sashal@kernel.org> References: <20240617132739.2590390-1-sashal@kernel.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore X-stable-base: Linux 5.4.278 Content-Transfer-Encoding: 8bit From: Eric Dumazet [ Upstream commit cf28ff8e4c02e1ffa850755288ac954b6ff0db8c ] As explained in commit 1378817486d6 ("tipc: block BH before using dst_cache"), net/core/dst_cache.c helpers need to be called with BH disabled. ila_output() is called from lwtunnel_output() possibly from process context, and under rcu_read_lock(). We might be interrupted by a softirq, re-enter ila_output() and corrupt dst_cache data structures. Fix the race by using local_bh_disable(). Signed-off-by: Eric Dumazet Acked-by: Paolo Abeni Link: https://lore.kernel.org/r/20240531132636.2637995-5-edumazet@google.com Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin --- net/ipv6/ila/ila_lwt.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/net/ipv6/ila/ila_lwt.c b/net/ipv6/ila/ila_lwt.c index 422dcc691f71c..6a6a30e82810d 100644 --- a/net/ipv6/ila/ila_lwt.c +++ b/net/ipv6/ila/ila_lwt.c @@ -58,7 +58,9 @@ static int ila_output(struct net *net, struct sock *sk, struct sk_buff *skb) return orig_dst->lwtstate->orig_output(net, sk, skb); } + local_bh_disable(); dst = dst_cache_get(&ilwt->dst_cache); + local_bh_enable(); if (unlikely(!dst)) { struct ipv6hdr *ip6h = ipv6_hdr(skb); struct flowi6 fl6; @@ -86,8 +88,11 @@ static int ila_output(struct net *net, struct sock *sk, struct sk_buff *skb) goto drop; } - if (ilwt->connected) + if (ilwt->connected) { + local_bh_disable(); dst_cache_set_ip6(&ilwt->dst_cache, dst, &fl6.saddr); + local_bh_enable(); + } } skb_dst_set(skb, dst); -- 2.43.0