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 1069B33E377; Mon, 20 Apr 2026 16:02:03 +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=1776700924; cv=none; b=CPa8/54bPwoA5q+45QVMwmYFNnh65NGeWas1q7g4TKjXJE2ssCkPsS50Mpyufx8Dszi5F/Fv/cSNVDvxO5KIcY7IGeyY3lVJ68rkb9cqKJOYbh4aum14twrXhcUkd4eH1ZVlfHmAc6yy3h6VHAk14r4w6cKX0fynoqx9bsmO618= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1776700924; c=relaxed/simple; bh=+UXvSXHUufANpCH9O+7BYqZ6xhqYzAbcz4CDjS1dmKc=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=t7Wznj/H0yUrNjK6wSNi7q6zDyHteaoCAOzCH3Tuvs6zyeGcUi2gqlC4AyT2Rg9ml01cddCOF9y9uefrpkC3fZQokdmxU1bTFTS98gD1v13dyaYCJC6w9QCz7NYCHasQzSOFHG4CedHSbcc5YXNnnWsGuyFzyK0xQ4dMh0y1gyg= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=EZ6MhoAS; 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="EZ6MhoAS" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 5908AC19425; Mon, 20 Apr 2026 16:02:03 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1776700923; bh=+UXvSXHUufANpCH9O+7BYqZ6xhqYzAbcz4CDjS1dmKc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=EZ6MhoAS9DeAKe+Ck49Tz+rXsx4nBpFzG8aA8m/uwpE+X5/zibDz0MlKtX5NVLg+c bQVEn+GpuvBkUtpkpWk9UAyjJZoup4gSTZeaGf+UTcdB8nAT+6yZTpCdYETD8OBWVp AIiYOnY5rbzv+IaXOXkzmBx5Bj5jX2ptRNGN3xuY= 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 6.18 070/198] net: sched: act_csum: validate nested VLAN headers Date: Mon, 20 Apr 2026 17:40:49 +0200 Message-ID: <20260420153938.131013607@linuxfoundation.org> X-Mailer: git-send-email 2.53.0 In-Reply-To: <20260420153935.605963767@linuxfoundation.org> References: <20260420153935.605963767@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 6.18-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 0939e6b2ba4d1..3a377604ad343 100644 --- a/net/sched/act_csum.c +++ b/net/sched/act_csum.c @@ -604,8 +604,12 @@ 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