From nobody Tue Mar 3 03:59:57 2026 Received: from fanzine2.igalia.com (fanzine2.igalia.com [213.97.179.56]) (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 DE99D311973; Mon, 2 Mar 2026 21:26:51 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=213.97.179.56 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1772486813; cv=none; b=DoH4s9EwFm62NErJMWgMAvb9/CxTAHOGCFfOXrNl34tdJjiFHD4kzFcnMruJfuEg8f0rGOONMZHTbPbOkGMbZMYkQBVSye53XChhVJ7lAvJC7F4ptxtR+IaMYi4GrGK0CfxCyv0QWGX3e4DWe36fVWj+gTxneAaymv/b5k8nmek= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1772486813; c=relaxed/simple; bh=wCbiKpSuM+Y2Tev+vgu0NocaBsr9LObSpGSJZxBalas=; h=From:To:Subject:Date:Message-ID:MIME-Version; b=Hsy4J92yWNBHVSZ66yz/KsfC1gwSDB88XQ5I/gW1qIuaGruzV/4Ks0gkn3yQva3DXtlCPiap1Ch4Rc+CEIUXb1Z/o7iMV0aFkgXRIJzpzLoV9QCcdSGpUTcHSd7yM4fWQtOQzOdxlsBnrvjygbleEmdKqiNMl1M5ppyJG3c91u4= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=igalia.com; spf=pass smtp.mailfrom=igalia.com; dkim=pass (2048-bit key) header.d=igalia.com header.i=@igalia.com header.b=FENQnDM2; arc=none smtp.client-ip=213.97.179.56 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=igalia.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=igalia.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=igalia.com header.i=@igalia.com header.b="FENQnDM2" DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=igalia.com; s=20170329; h=Content-Transfer-Encoding:MIME-Version:Message-ID:Date:Subject: To:From:Sender:Reply-To:Cc:Content-Type:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: In-Reply-To:References:List-Id:List-Help:List-Unsubscribe:List-Subscribe: List-Post:List-Owner:List-Archive; bh=HIY0/QhmjXMLqc/7+DI6IQB27NYnFLrMfhd++B8Q+yo=; b=FENQnDM20xwRKTgS5hHaA+4n1r D+dD1r90GcuvnIv+zwPJndL/vGdV7ZJrytujvuw0H9G3e2QuOTOu7epVmvltkk0mm466f4h9otnai g9qmNIyxjk6R2QrADCu8gQcTb9EZuDQvfdWqB+8iDsJRW6r3qMSZeDrtghxNCJS5/JMkio+/tP6A5 TR2PYL9CG+Us6F0PRQp67YgPM95xJMICqPhKS/OvjB/DQOGpscJlbjfjRTntonTT0f8ljUwq+1e2P UowXuV3slvqUDPXUSRTuhddmUGZ5IE9mnB92DW/oMnKsA9WsLk5QOArLE3sZE4fjwoCG9HA8AD/x/ aARwXSwg==; Received: from [179.221.50.217] (helo=toolbx) by fanzine2.igalia.com with esmtpsa (Cipher TLS1.3:ECDHE_X25519__RSA_PSS_RSAE_SHA256__AES_256_GCM:256) (Exim) id 1vxAmp-0089NM-Fk; Mon, 02 Mar 2026 22:26:43 +0100 From: Helen Koike To: pablo@netfilter.org, fw@strlen.de, phil@nwl.cc, netfilter-devel@vger.kernel.org, coreteam@netfilter.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org, kernel-dev@igalia.com, koike@igalia.com Subject: [PATCH] netfilter: nf_tables: fix use-after-free on ops->dev Date: Mon, 2 Mar 2026 18:26:05 -0300 Message-ID: <20260302212605.689909-1-koike@igalia.com> X-Mailer: git-send-email 2.53.0 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" struct nf_hook_ops has a pointer to dev, which can be used by __nf_unregister_net_hook() after it has been freed by tun_chr_close(). Fix it by calling dev_hold() when saving dev to ops struct. Reported-by: syzbot+bb9127e278fa198e110c@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=3Dbb9127e278fa198e110c Signed-off-by: Helen Koike --- net/netfilter/nf_tables_api.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/net/netfilter/nf_tables_api.c b/net/netfilter/nf_tables_api.c index fd7f7e4e2a43..00b5f900a51d 100644 --- a/net/netfilter/nf_tables_api.c +++ b/net/netfilter/nf_tables_api.c @@ -352,6 +352,7 @@ static void nft_netdev_hook_free_ops(struct nft_hook *h= ook) =20 list_for_each_entry_safe(ops, next, &hook->ops_list, list) { list_del(&ops->list); + dev_put(ops->dev); kfree(ops); } } @@ -2374,6 +2375,7 @@ static struct nft_hook *nft_netdev_hook_alloc(struct = net *net, err =3D -ENOMEM; goto err_hook_free; } + dev_hold(dev); ops->dev =3D dev; list_add_tail(&ops->list, &hook->ops_list); } --=20 2.53.0