From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail.netfilter.org (mail.netfilter.org [217.70.190.124]) (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 86232446857; Mon, 5 Oct 2026 23:05:39 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=217.70.190.124 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1791241544; cv=none; b=pRMuc9m6zk+YYbvMSYJn6xUqEKp2oZOQEZsQva9IBg5XIFvjit4WRecvIZaCvyCdKHpY8FVdueAQKpxXHGWL2hGsN5rw02gwnbO050JrcFjJ+VjWxsSLeRNbxN4sOmYSBaemt39hHdZ2qpwTEc4NFM+kDGaA6aCEunkQhhX9iFw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1791241544; c=relaxed/simple; bh=LXlPLXZ616GpRTYLWPN6QbfAdOSQGfoV+w7HBJmol5g=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=I657/loFIaQfx3UhEpS3R7vjlSsgE2mWPPDvxk3Fznk6O1PxK3aiDkFcwwMIPFGROkSMCPWkVBQ+yvgP4O2+yANsm7aSI79hf601Yl7WoHOQl5rf5oFYQfG5sz6Zh5MJHNgrpLsiMW50Sb8wq51wrXfq1vVDvXlqNg5iVYNL2ME= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=netfilter.org; spf=pass smtp.mailfrom=netfilter.org; dkim=pass (2048-bit key) header.d=netfilter.org header.i=@netfilter.org header.b=O0WG+DDS; arc=none smtp.client-ip=217.70.190.124 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=netfilter.org Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=netfilter.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=netfilter.org header.i=@netfilter.org header.b="O0WG+DDS" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=netfilter.org; s=2025; t=1791241536; bh=c99KASve6Ees45vUEP4qfb1SchJPRipEWmwIvCrBhYo=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=O0WG+DDS1ZcrqM/HOs5kqAGYM3cmZsr+E1MK0535kpVbYQjE6HR3/lr1TOpTBNXri anFPAeemjcgo7+/jWX1Wqe664D/pGGlxJ2qPSlG0/trXdPraCRWzRhK9ymEzZvWcIU awTH7lH7eYqudzjEwBmuQl/4TLrqXydDl7vQqEaeJDOekp3u/DEe/wG50G5TDRYEB0 xee83E+aB47bmwu7+QaN1XG43bRT4giq+g41PQP4TOLMb1qlaALnLzhdY8M9hx5OxL WnzL1N8OwAgw+1hzu3Ko9kTc6Z5GQH2JlK0ymxsDr87O+Eyrv/2xzvCe78hE4EoQKW vUCp8OLVLY23Q== Received: from netfilter.org (mail-agni [217.70.190.124]) by mail.netfilter.org (Postfix) with UTF8SMTPSA id 6666060058; Tue, 6 Oct 2026 01:05:36 +0200 (CEST) Date: Tue, 6 Oct 2026 01:05:33 +0200 From: Pablo Neira Ayuso To: =?utf-8?B?SsOpcsOpbXk=?= Jean Cc: Florian Westphal , Phil Sutter , netfilter-devel@vger.kernel.org, coreteam@netfilter.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org, stable@vger.kernel.org Subject: Re: [PATCH nf] netfilter: nft_set_rbtree: reject expired interval ends Message-ID: References: <20261005200404.3544062-2-Jeremy.Jean@oss.cyber.gouv.fr> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: multipart/mixed; boundary="qEnWkv4Thx0oRRZb" Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20261005200404.3544062-2-Jeremy.Jean@oss.cyber.gouv.fr> --qEnWkv4Thx0oRRZb Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit Hi, On Mon, Oct 05, 2026 at 08:04:05PM +0000, Jérémy Jean wrote: > Consider two ranges in a netfilter verdict map: > * keys 10-19 accept packets, and > * keys 30-39 jump to chain 'victim'. > Now, delete the end marker at 20. The lookup array now uses element 30 > as the first range's end, so an INTERVAL_END query for key 15 returns > element 30, including its jump verdict and chain pointer. This can make > KASAN reports a UAF after the GC releases reference chain for 30 that > has expired: > > BUG: KASAN: slab-use-after-free in nft_verdict_dump+0xdd/0x110 > Read of size 8 at addr ff110000009dfb58 by task repro/50 > ... > Call Trace: > ... > nft_verdict_dump+0xdd/0x110 > nft_data_dump+0x4d/0x80 > nf_tables_fill_setelem+0x30b/0x8a0 > ? __asan_memcpy+0x3c/0x60 > nf_tables_fill_setelem_info+0x1b0/0x200 > nft_get_set_elem+0x3fd/0x4b0 > ... > Freed by task 24: > ... > kfree+0x1a5/0x280 > nf_tables_trans_destroy_work+0x2cb/0x520 > > Reject expired endpoints in nft_rbtree_get() before returning them. > > Fixes: 2aa34191f06f ("netfilter: nft_set_rbtree: use binary search array in get command") > Cc: stable@vger.kernel.org > Assisted-by: LLM > Signed-off-by: Jérémy Jean > --- > net/netfilter/nft_set_rbtree.c | 2 ++ > 1 file changed, 2 insertions(+) > > diff --git a/net/netfilter/nft_set_rbtree.c b/net/netfilter/nft_set_rbtree.c > index 9894832..1fd9cbe 100644 > --- a/net/netfilter/nft_set_rbtree.c > +++ b/net/netfilter/nft_set_rbtree.c > @@ -187,6 +187,8 @@ nft_rbtree_get(const struct net *net, const struct nft_set *set, > if (flags & NFT_SET_ELEM_INTERVAL_END) { > if (!interval->to) > return NULL; > + if (nft_set_elem_expired(interval->to)) > + return ERR_PTR(-ENOENT); > > rbe = container_of(interval->to, struct nft_rbtree_elem, ext); > } else { > -- > 2.47.3 Can you test this fix instead? Thanks --qEnWkv4Thx0oRRZb Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="tentative-fix.patch" diff --git a/net/netfilter/nft_set_rbtree.c b/net/netfilter/nft_set_rbtree.c index 12431b55752f..fbe1750f1ca2 100644 --- a/net/netfilter/nft_set_rbtree.c +++ b/net/netfilter/nft_set_rbtree.c @@ -1091,7 +1091,8 @@ static void nft_rbtree_commit(struct nft_set *set) * representation. Use next start element to complete this * interval. */ - if (nft_rbtree_interval_start(rbe) && + if (nft_set_is_anonymous(set) && + nft_rbtree_interval_start(rbe) && nft_rbtree_interval_start(prev_rbe) && priv->array_next->intervals[num_intervals].from) priv->array_next->intervals[num_intervals++].to = &prev_rbe->ext; --qEnWkv4Thx0oRRZb--