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 9F1AE19A288; Fri, 24 Apr 2026 13:34:58 +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=1777037698; cv=none; b=u/yFgtv/kRnXnK+x/ExUMDrF0tbwYCKXS1M4hlzLcSvNKHnzLbjQH49TuV/RZuDIneRg14PXaIrz0NCd5ydNoB2h9M1UMpuMNhXpIMvOHzKUXt0XcnvFyANgS6P1QQ+siswu/kILaiKV60gcVBwS2vN/pAF/I5wJ91O7CWCOW0E= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1777037698; c=relaxed/simple; bh=+WOETVRyr4oT/en00OgEmG7R0AwgfmAjc8zUqlANVXc=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=FxBgPcUWGBoV1XjbAHK6FE5z8E1+TD9OEUCIBMI6A8bBYjMk71g9mTruw9RBW5NSYEYcC5j1Ze7DYwimR+rlvcdD0bS5L5UE658tLaI30nS7h0U6Jyk3O7wtWfopXCj3HZ3kl61oAkIiVp89OMekxygOMGqylH8jV6X8rUtYwKM= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=EuU8e3j6; 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="EuU8e3j6" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 35B44C19425; Fri, 24 Apr 2026 13:34:58 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1777037698; bh=+WOETVRyr4oT/en00OgEmG7R0AwgfmAjc8zUqlANVXc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=EuU8e3j6gB607YRmMC64QAVMDft7rMaKdGj8wSzuLJjLs84VNW5KKr7dFRKTXZ6ex fumYK5LR5LppiyloUV79+3LChenLXET3Shh7DnHd6v5vP2mK+WeZoGk6SKTI0vkWa1 0nsU0Etp5byCcYW4t34axVgOmyN0egyAJJ8HdqRE= 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 6.6 035/166] net: sched: act_csum: validate nested VLAN headers Date: Fri, 24 Apr 2026 15:29:09 +0200 Message-ID: <20260424132540.212586431@linuxfoundation.org> X-Mailer: git-send-email 2.53.0 In-Reply-To: <20260424132532.812258529@linuxfoundation.org> References: <20260424132532.812258529@linuxfoundation.org> User-Agent: quilt/0.69 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: 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 8ed285023a40a..e8583dc721b6a 100644 --- a/net/sched/act_csum.c +++ b/net/sched/act_csum.c @@ -603,8 +603,12 @@ TC_INDIRECT_SCOPE int tcf_csum_act(struct sk_buff *skb, 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