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 C23B42FB093; Wed, 28 Jan 2026 15:42:55 +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=1769614975; cv=none; b=m68pBaG6fvNzR1oTKuaO7goD6Q6S8ehECPZpnlGAA+OnDtELUQGyIC2E36jpVBMqwld65E1M3Sm3lYChV9+/pnl6GI8JFpp3YzPoCCiT5l/cz9Y6StaSficqazyqIp3cH8GawW87h6tYTK7+DcrkrrG8OqOoDQth/70eH5H32Wk= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1769614975; c=relaxed/simple; bh=FHGn+1UFq5pk30UPkk4P6skYVM5H3cc7t8P1WA6HRzA=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=OemKjOFpmipzm0CCzRF2LouwUmXuWGgrrpPNrZgA8DyapF+TcgcaXVtKML2TKJxgzWfEkxnHsRqha6hu6HZpOisHLSmYjvqysIzCdxvZQa4CfYdKJRKi1coH3U3AFviIV3+6MB/5P/8ZC8yswJlBciMd59jT7g89Th6dtEqOi50= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=AwBVXNCa; 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="AwBVXNCa" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 1487FC2BCAF; Wed, 28 Jan 2026 15:42:54 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1769614975; bh=FHGn+1UFq5pk30UPkk4P6skYVM5H3cc7t8P1WA6HRzA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=AwBVXNCas5GNweYs++zZHEWACNKDF3Er7qd7Bl9Y/30QeHhPZvnh3NkrxAiPk/4e/ q/30TXhlgVP60i4RK5a+YWzxY6Dgf61cWZTTU3Fb2vxqSNvKFYztSq2EW8oSci7Gzk 8lScpxGOCxzBKI8jbRL6B5Xk7IIMQ+jYN0RQ11Yg= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Jamal Hadi Salim , Jakub Kicinski , Sasha Levin Subject: [PATCH 6.12 040/169] net/sched: qfq: Use cl_is_active to determine whether class is active in qfq_rm_from_ag Date: Wed, 28 Jan 2026 16:22:03 +0100 Message-ID: <20260128145335.463296850@linuxfoundation.org> X-Mailer: git-send-email 2.52.0 In-Reply-To: <20260128145334.006287341@linuxfoundation.org> References: <20260128145334.006287341@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 6.12-stable review patch. If anyone has any objections, please let me know. ------------------ From: Jamal Hadi Salim [ Upstream commit d837fbee92453fbb829f950c8e7cf76207d73f33 ] This is more of a preventive patch to make the code more consistent and to prevent possible exploits that employ child qlen manipulations on qfq. use cl_is_active instead of relying on the child qdisc's qlen to determine class activation. Fixes: 462dbc9101acd ("pkt_sched: QFQ Plus: fair-queueing service at DRR cost") Signed-off-by: Jamal Hadi Salim Link: https://patch.msgid.link/20260114160243.913069-3-jhs@mojatatu.com Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin --- net/sched/sch_qfq.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/net/sched/sch_qfq.c b/net/sched/sch_qfq.c index d8dabc1a620bd..c7c8e8dde31d1 100644 --- a/net/sched/sch_qfq.c +++ b/net/sched/sch_qfq.c @@ -373,7 +373,7 @@ static void qfq_rm_from_agg(struct qfq_sched *q, struct qfq_class *cl) /* Deschedule class and remove it from its parent aggregate. */ static void qfq_deact_rm_from_agg(struct qfq_sched *q, struct qfq_class *cl) { - if (cl->qdisc->q.qlen > 0) /* class is active */ + if (cl_is_active(cl)) /* class is active */ qfq_deactivate_class(q, cl); qfq_rm_from_agg(q, cl); -- 2.51.0