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 DCA7412CD96; Tue, 30 Apr 2024 11:08:01 +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=1714475282; cv=none; b=Bbq1OSiIF/BXaU9tuwKJCpk6aX2+Sn7rpcXkNX+9yUIhBU1Z77HLeTa3z/WYgy1JiCOVYZTJtTYEwdpfmmydkeKKjk+Y4eWXELGoxPM+8guWnedS/0FrRCK46aXWe9nQgmKTzqCExWF8CZk5RNQ34gWhAs6E7IIlZAH7DVzZlN4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1714475282; c=relaxed/simple; bh=r1Js36AatEvX0jB4QHD2H5WLHBNybBvSIFHgqMrSCgI=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=K5dPN/Nuy+0PoGgYeVxsRZXFw96HYiOJtiN2LQvE1UWCmK2oc4zuUSXBQyg8r059mjFYGsWSNvSgrCfDfS7WkcAT/ApZWgxhIRhfTfOzMVUXJWkUq97/IDK5uDy65nzGhtBmQWT0xyn0IT5mQtVF/gHutkC7ocVdbrLYa1rTo2g= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=YWEjLvva; 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="YWEjLvva" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 64591C2BBFC; Tue, 30 Apr 2024 11:08:01 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1714475281; bh=r1Js36AatEvX0jB4QHD2H5WLHBNybBvSIFHgqMrSCgI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=YWEjLvvaiiyjBZPQItlCvWebqU3zHmCwS0i8c1BaJ2oJS0xu/Shan/52+HUCHx87F TbtYwuuQnjssmjjVDTCK5gwAGe9ec/7/C4VHMOGnJIy1tGzqfhoH26Y2PX46xYWnXc rcyK5G8gDpYvvqMjL5o+SyYVd90g9MV4Bwte7MNU= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Eric Dumazet , Andreas Roeseler , David Ahern , "David S. Miller" , Sasha Levin Subject: [PATCH 6.6 050/186] icmp: prevent possible NULL dereferences from icmp_build_probe() Date: Tue, 30 Apr 2024 12:38:22 +0200 Message-ID: <20240430103059.485279088@linuxfoundation.org> X-Mailer: git-send-email 2.44.0 In-Reply-To: <20240430103058.010791820@linuxfoundation.org> References: <20240430103058.010791820@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 6.6-stable review patch. If anyone has any objections, please let me know. ------------------ From: Eric Dumazet [ Upstream commit c58e88d49097bd12dfcfef4f075b43f5d5830941 ] First problem is a double call to __in_dev_get_rcu(), because the second one could return NULL. if (__in_dev_get_rcu(dev) && __in_dev_get_rcu(dev)->ifa_list) Second problem is a read from dev->ip6_ptr with no NULL check: if (!list_empty(&rcu_dereference(dev->ip6_ptr)->addr_list)) Use the correct RCU API to fix these. v2: add missing include Fixes: d329ea5bd884 ("icmp: add response to RFC 8335 PROBE messages") Signed-off-by: Eric Dumazet Cc: Andreas Roeseler Reviewed-by: David Ahern Signed-off-by: David S. Miller Signed-off-by: Sasha Levin --- net/ipv4/icmp.c | 12 ++++++++++-- 1 file changed, 10 insertions(+), 2 deletions(-) diff --git a/net/ipv4/icmp.c b/net/ipv4/icmp.c index b8607763d113a..3b221643206de 100644 --- a/net/ipv4/icmp.c +++ b/net/ipv4/icmp.c @@ -92,6 +92,7 @@ #include #include #include +#include /* * Build xmit assembly blocks @@ -1032,6 +1033,8 @@ bool icmp_build_probe(struct sk_buff *skb, struct icmphdr *icmphdr) struct icmp_ext_hdr *ext_hdr, _ext_hdr; struct icmp_ext_echo_iio *iio, _iio; struct net *net = dev_net(skb->dev); + struct inet6_dev *in6_dev; + struct in_device *in_dev; struct net_device *dev; char buff[IFNAMSIZ]; u16 ident_len; @@ -1115,10 +1118,15 @@ bool icmp_build_probe(struct sk_buff *skb, struct icmphdr *icmphdr) /* Fill bits in reply message */ if (dev->flags & IFF_UP) status |= ICMP_EXT_ECHOREPLY_ACTIVE; - if (__in_dev_get_rcu(dev) && __in_dev_get_rcu(dev)->ifa_list) + + in_dev = __in_dev_get_rcu(dev); + if (in_dev && rcu_access_pointer(in_dev->ifa_list)) status |= ICMP_EXT_ECHOREPLY_IPV4; - if (!list_empty(&rcu_dereference(dev->ip6_ptr)->addr_list)) + + in6_dev = __in6_dev_get(dev); + if (in6_dev && !list_empty(&in6_dev->addr_list)) status |= ICMP_EXT_ECHOREPLY_IPV6; + dev_put(dev); icmphdr->un.echo.sequence |= htons(status); return true; -- 2.43.0