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 06987433BCE for ; Mon, 20 Jul 2026 15:56:15 +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=1784562978; cv=none; b=OfxfQu/Io3QGTnoXO5oU4ZhbpP6ogzt6Hccw0sfn6sJsSv0WV1cesBoNb0ghdDyzB1Gc84NhRWp2v+YTtOm+hDJ0FVlBZlYtrzhyGy7Y3rm19AgXObyJ5kSbVjpeMdQD2Sx6XD/V44uHhrFtEN17MxgIA6lvotmTz4etHmjIATM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784562978; c=relaxed/simple; bh=62mLoXoMkESOpcTXd4V402FTH8VUz4iU11eQcYVsnMk=; h=Subject:To:Cc:From:Date:Message-ID:MIME-Version:Content-Type; b=XppsIC1mSqMJ2ctaXMFP49Bl7trGDksoAkLvfOPybBIkecQZ5+/0YP95/iF1OHgK0NwGmm578FM0UwlAz7lLs714LOYPmJ4pbkegCtXH6wxgNMVGS/kT+tJctvLJEnv4wJm8C8iWwxC4xZkwSutUnGBfQ0VPWhAnwlukw5oQYIQ= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=oIA+zag/; 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="oIA+zag/" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 3652B1F000E9; Mon, 20 Jul 2026 15:56:15 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1784562975; bh=oj4KWEk4RyrQmw47UqP0IYcDVwYb6XplDzLZLMZAVuE=; h=Subject:To:Cc:From:Date; b=oIA+zag/uRsJpwr9nRZ5qTAR+DtcAqFcPdxaCc4pY+i2KfPWNvTF9W8x9NIv2DsnS 7Kx7TWo3trtm46LZsxn3I6W4699m7GOVW+qzZAZDi381Z5NVa6W59fs3m6ZzxJOjnV 6eKQNWBFXl7ZfYzEYaSzyC4glFwpxotE7c3aKD8Q= Subject: FAILED: patch "[PATCH] net/sched: act_ct: preserve tc_skb_cb across defragmentation" failed to apply to 6.1-stable tree To: xizh2024@lzu.edu.cn,bird@lzu.edu.cn,kuba@kernel.org,n05ec@lzu.edu.cn,tomapufckgml@gmail.com,yifanwucs@gmail.com,yuantan098@gmail.com Cc: From: Date: Mon, 20 Jul 2026 17:52:18 +0200 Message-ID: <2026072018-sixtieth-darkness-30c6@gregkh> Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=ANSI_X3.4-1968 Content-Transfer-Encoding: 8bit The patch below does not apply to the 6.1-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to . To reproduce the conflict and resubmit, you may use the following commands: git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.1.y git checkout FETCH_HEAD git cherry-pick -x 9092e15defbe6c7bc241c306093ca9d358a578e7 # git commit -s git send-email --to '' --in-reply-to '2026072018-sixtieth-darkness-30c6@gregkh' --subject-prefix 'PATCH 6.1.y' 'HEAD^..' Possible dependencies: thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >From 9092e15defbe6c7bc241c306093ca9d358a578e7 Mon Sep 17 00:00:00 2001 From: Zihan Xi Date: Sun, 14 Jun 2026 01:42:39 +0800 Subject: [PATCH] net/sched: act_ct: preserve tc_skb_cb across defragmentation tcf_ct_handle_fragments() calls nf_ct_handle_fragments() without saving and restoring skb->cb. The defrag helper clears IPCB/IP6CB, which aliases the tc_skb_cb/qdisc_skb_cb control buffer. Fragmented traffic through act_ct therefore loses qdisc metadata such as pkt_segs and can trigger WARN_ON_ONCE() in qdisc_pkt_segs() when panic_on_warn is enabled. Save and restore the full tc_skb_cb around nf_ct_handle_fragments(), matching the pattern used by ovs_ct_handle_fragments(). Fixes: ec624fe740b4 ("net/sched: Extend qdisc control block with tc control block") Cc: stable@vger.kernel.org Reported-by: Yuan Tan Reported-by: Yifan Wu Reported-by: Juefei Pu Reported-by: Xin Liu Signed-off-by: Zihan Xi Signed-off-by: Ren Wei Link: https://patch.msgid.link/510c51217fd7aaf29c6dc298bab8d643fe229b1c.1781358692.git.xizh2024@lzu.edu.cn Signed-off-by: Jakub Kicinski diff --git a/net/sched/act_ct.c b/net/sched/act_ct.c index 6158e13c98d3..d47a82f9ac6c 100644 --- a/net/sched/act_ct.c +++ b/net/sched/act_ct.c @@ -844,11 +844,11 @@ static int tcf_ct_handle_fragments(struct net *net, struct sk_buff *skb, u8 family, u16 zone, bool *defrag) { enum ip_conntrack_info ctinfo; + struct tc_skb_cb cb; struct nf_conn *ct; int err = 0; bool frag; u8 proto; - u16 mru; /* Previously seen (loopback)? Ignore. */ ct = nf_ct_get(skb, &ctinfo); @@ -862,12 +862,13 @@ static int tcf_ct_handle_fragments(struct net *net, struct sk_buff *skb, if (err || !frag) return err; - err = nf_ct_handle_fragments(net, skb, zone, family, &proto, &mru); + cb = *tc_skb_cb(skb); + err = nf_ct_handle_fragments(net, skb, zone, family, &proto, &cb.mru); if (err) return err; *defrag = true; - tc_skb_cb(skb)->mru = mru; + *tc_skb_cb(skb) = cb; return 0; }