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 8EC66391E51; Sat, 17 Oct 2026 17:12:57 +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=1792257178; cv=none; b=nBurQPg5MxLkdSNhYYEDvXI8MHuCwo/MM3dLk53t6Cd8vNFqwUyhwaGyn5qMyfwFUOgtGtyirFBp+PcYykBMd6JCXOkWUohXd26qGHH3qZNQs9yBZ/DoxOktH51VOFiNwObVfva1DRej1+OSROFfFDOkiMFBiWkQ26Xoz6x9cBw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1792257178; c=relaxed/simple; bh=CC79MFt6jyDvS1y8n/nusf7EcvBgg7WK6EJzVB5oP+o=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=ZF5vsL021Okx3/qVfKBz/qZlClxdHEXb059QhzPHHcoK7Z1vL4XTLd/x/jQKcUEi8sZcMY4pBrNJsbAwmkrlf8ftZJ4MgPAA+0tYWv7xdHBHFLWrugQ2df6Bvpd+jV3gy51Y6muhHCe24zbnR1gLPPlj58JhDG0xfalLpl332aE= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=N5skvSxw; 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="N5skvSxw" Received: by smtp.kernel.org (Postfix) with ESMTPSA id A2EAC1F000C4; Sat, 17 Oct 2026 17:12:56 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1792257177; bh=ZxOKKETrhhFS8S1ydlEoLlcS78tOcfeIcX6Q7ZqqnPg=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=N5skvSxwR4w8lUUHvykmb1mqnD5ymBvvKUNFwN94Kxc+firRdJ/AFbMHjgWG8UyFz ho+OqFpuWQ1t8b8/kYY9IIh5h+mRAn8Q/wRrI1MwHhq0tu8/on2VoDsfAgxTtwSQgL fEmt5CmiwlxmKgAO1agpPGpkTGe4Zw5NuTDN3kn8= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Ramses de Norre , =?UTF-8?q?Toke=20H=C3=B8iland-J=C3=B8rgensen?= , Eric Dumazet , "Jason A. Donenfeld" , Jakub Kicinski Subject: [PATCH 6.6 0474/1674] wireguard: queueing: preserve tstamp_type when encapsulating packet Date: Sat, 17 Oct 2026 17:45:46 +0200 Message-ID: <20261017160443.283468433@linuxfoundation.org> X-Mailer: git-send-email 2.56.0 In-Reply-To: <20261017160431.119607952@linuxfoundation.org> References: <20261017160431.119607952@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-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit 6.6-stable review patch. If anyone has any objections, please let me know. ------------------ From: Ramses de Norre commit 65ab9de4bdd4c05d8277cfc20ae0b9f5aff60897 upstream. Sending traffic through a wireguard tunnel on a host using the fq qdisc fills the log with: fq: likely mono tstamp with tstamp_type 0 An skb carries a timestamp in skb->tstamp and, separately, a skb->tstamp_type field recording which clock that timestamp came from. The two have to agree. When wireguard encapsulates a packet it calls wg_reset_packet(), which clears the fields that must not leak from the inner packet into the tunnel packet. It does so in two steps: skb_scrub_packet(skb, true); memset(&skb->headers, 0, sizeof(skb->headers)); skb_scrub_packet() deliberately keeps skb->tstamp when it holds a monotonic timestamp: that value is the time the packet is scheduled to be sent, and the qdisc still needs it. The memset then zeroes skb->tstamp_type, because that field sits inside the headers group while skb->tstamp does not. The packet therefore leaves wireguard carrying a monotonic timestamp labelled as a realtime one. Nothing noticed until commit c4f796c4f16b ("net_sched: sch_fq: convert skb->tstamp if not monotonic"): fq used to assume every timestamp was monotonic. It now consults tstamp_type, spots the mismatch, warns, and falls back to treating the value as monotonic. Pacing still ends up correct, so the log spam is the actual problem. Save tstamp_type before the memset and restore it when encapsulating, next to the hash fields that are already carried over this way. When decapsulating it stays zeroed, which is right: an incoming packet's timestamp is a realtime receive timestamp. Fixes: d98d58a00261 ("net: Set skb->mono_delivery_time and clear it after sch_handle_ingress()") Signed-off-by: Ramses de Norre Reviewed-by: Toke Høiland-Jørgensen Reviewed-by: Eric Dumazet Cc: stable@vger.kernel.org Signed-off-by: Jason A. Donenfeld Link: https://patch.msgid.link/20261008130124.724119-3-Jason@zx2c4.com Signed-off-by: Jakub Kicinski Signed-off-by: Greg Kroah-Hartman --- drivers/net/wireguard/queueing.h | 2 ++ 1 file changed, 2 insertions(+) --- a/drivers/net/wireguard/queueing.h +++ b/drivers/net/wireguard/queueing.h @@ -78,12 +78,14 @@ static inline void wg_reset_packet(struc u8 l4_hash = skb->l4_hash; u8 sw_hash = skb->sw_hash; u32 hash = skb->hash; + u8 tstamp_type = skb->tstamp_type; skb_scrub_packet(skb, true); memset(&skb->headers, 0, sizeof(skb->headers)); if (encapsulating) { skb->l4_hash = l4_hash; skb->sw_hash = sw_hash; skb->hash = hash; + skb->tstamp_type = tstamp_type; } skb->queue_mapping = 0; skb->nohdr = 0;