From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 4B7D52BE621; Sat, 30 May 2026 16:27:13 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1780158434; cv=none; b=cVcrrVkp3JNmvwMNY8B5Z2nKZvlvqeT7Nodpsh+aCA7GJSGnywiQFxoPPTJK2BNYZpAUL6g1QAznqQ7R4+ovAZu6+sRQQeBTO1mToe8DwPXoa8RrKfINHZaiP42DlYrLIuA4IuFM278LPrctwjBKzZCLWJW1m6IUL5ShnWT67qI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1780158434; c=relaxed/simple; bh=M+6KDIm3SY1x3zUxKsTS72Jne1W3ISZHQ3EUM95CSTw=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=oZ2u+BeY6JukT9jt23A2q2cj747k0dAfhHhxHXsdqWBNZfJ71tdqR8y6uZ/2HEsY5Ea+uzP1ut2J85Wc9hUt8ZxfdCDR+QJH3w/62kF3l+1NBR+CaBm5U+Wmze0m6Enug9eYRd6GGFAyp3OKpicO0x1yvWpLGXRTZhQ0rcMVKjo= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=erfG9b21; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="erfG9b21" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 3B5BE1F00893; Sat, 30 May 2026 16:27:11 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1780158433; bh=pX7bX6U8wcJoeHOwmEMeuRWyhBc7VayUi/I0wM8dhDo=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=erfG9b21olVC2GKfshIUZtRNJdVJAn3eEgNuyQwKeZ64KvkflLLZt7WS27ET/ucml Cv+2D6AU5vKOqDuw+y3XiuGo/OPchUSE5IqeefTcUegSHPF1Z6QlBDY97rcOsAnRv5 GCQfOeoCDPiMnWNuzmrSN+966vfoIzFfm5YxvTpU= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Yifan Wu , Juefei Pu , Yuan Tan , Xin Liu , Ren Wei , Ruide Cao , Ren Wei , Simon Horman , Jakub Kicinski , Sasha Levin Subject: [PATCH 6.1 033/969] net: sched: act_csum: validate nested VLAN headers Date: Sat, 30 May 2026 17:52:37 +0200 Message-ID: <20260530160301.345202170@linuxfoundation.org> X-Mailer: git-send-email 2.53.0 In-Reply-To: <20260530160300.485627683@linuxfoundation.org> References: <20260530160300.485627683@linuxfoundation.org> User-Agent: quilt/0.69 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 6.1-stable review patch. If anyone has any objections, please let me know. ------------------ From: Ruide Cao [ Upstream commit c842743d073bdd683606cb414eb0ca84465dd834 ] tcf_csum_act() walks nested VLAN headers directly from skb->data when an skb still carries in-payload VLAN tags. The current code reads vlan->h_vlan_encapsulated_proto and then pulls VLAN_HLEN bytes without first ensuring that the full VLAN header is present in the linear area. If only part of an inner VLAN header is linearized, accessing h_vlan_encapsulated_proto reads past the linear area, and the following skb_pull(VLAN_HLEN) may violate skb invariants. Fix this by requiring pskb_may_pull(skb, VLAN_HLEN) before accessing and pulling each nested VLAN header. If the header still is not fully available, drop the packet through the existing error path. Fixes: 2ecba2d1e45b ("net: sched: act_csum: Fix csum calc for tagged packets") Reported-by: Yifan Wu Reported-by: Juefei Pu Co-developed-by: Yuan Tan Signed-off-by: Yuan Tan Suggested-by: Xin Liu Tested-by: Ren Wei Signed-off-by: Ruide Cao Signed-off-by: Ren Wei Reviewed-by: Simon Horman Link: https://patch.msgid.link/22df2fcb49f410203eafa5d97963dd36089f4ecf.1774892775.git.caoruide123@gmail.com Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin --- net/sched/act_csum.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/net/sched/act_csum.c b/net/sched/act_csum.c index 1366adf9b9091..bcef42a3ad645 100644 --- a/net/sched/act_csum.c +++ b/net/sched/act_csum.c @@ -602,8 +602,12 @@ static int tcf_csum_act(struct sk_buff *skb, const struct tc_action *a, protocol = skb->protocol; orig_vlan_tag_present = true; } else { - struct vlan_hdr *vlan = (struct vlan_hdr *)skb->data; + struct vlan_hdr *vlan; + if (!pskb_may_pull(skb, VLAN_HLEN)) + goto drop; + + vlan = (struct vlan_hdr *)skb->data; protocol = vlan->h_vlan_encapsulated_proto; skb_pull(skb, VLAN_HLEN); skb_reset_network_header(skb); -- 2.53.0