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 3374C126C18; Wed, 5 Feb 2025 13:49:49 +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=1738763389; cv=none; b=eqz+dSaHv2PHiMMdl2V1K/f5Vv0dhWm6/2hURV4Wnj7C9Bbs230vjoN1if1j/R+gwBfaSFaog7fJRenf7s0tXVgVX/EXcw/9PrZIO2w6GmwAHFTsblEXvh0PjdOp9Jso71Kr2jzUFJxBERrNmeYiov4xMXiOux5/QQd43qrlrjo= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1738763389; c=relaxed/simple; bh=f14kOU0TC3R4YhiiS8L0f9BG0lpuWBxxLfYLmhBYJhQ=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=G7UqVH0BEnKGB99e1G9UYrtSKbfDx63nae1FBwSUdNrUSfaAkWFXqGUrURBaxzg/P5d1Xgbpj5MfeUhLl9r5qfJT5JQ6uEXm93QO2WkuMSqSxgkN3u/9c47Dqc0rjS8eq0zE7559h2n3mxMkvGM6zpt4I0Yq8lmFxneXkeM41JE= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=BlucOcIs; 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="BlucOcIs" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 9402BC4CED1; Wed, 5 Feb 2025 13:49:48 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1738763389; bh=f14kOU0TC3R4YhiiS8L0f9BG0lpuWBxxLfYLmhBYJhQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=BlucOcIsSX1cRXugULq1NJcsfTWG8rdTOntSDokeRSyIAixf2peBSsB335BcpIJu4 IVFE9GkGP9+7xSUieyIGHQa35sVGt+7UFmye4sLDGkYeU2rehWvtNHgNKN/kP7DU4b 5tAKR5QD/V2gCjL1kbbTosOikITKJOsnd+D+T5bc= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Eric Dumazet , Simon Horman , Jakub Kicinski , Sasha Levin Subject: [PATCH 6.6 055/393] net_sched: sch_sfq: annotate data-races around q->perturb_period Date: Wed, 5 Feb 2025 14:39:34 +0100 Message-ID: <20250205134422.402596389@linuxfoundation.org> X-Mailer: git-send-email 2.48.1 In-Reply-To: <20250205134420.279368572@linuxfoundation.org> References: <20250205134420.279368572@linuxfoundation.org> User-Agent: quilt/0.68 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: Eric Dumazet [ Upstream commit a17ef9e6c2c1cf0fc6cd6ca6a9ce525c67d1da7f ] sfq_perturbation() reads q->perturb_period locklessly. Add annotations to fix potential issues. Signed-off-by: Eric Dumazet Reviewed-by: Simon Horman Link: https://lore.kernel.org/r/20240430180015.3111398-1-edumazet@google.com Signed-off-by: Jakub Kicinski Stable-dep-of: 10685681bafc ("net_sched: sch_sfq: don't allow 1 packet limit") Signed-off-by: Sasha Levin --- net/sched/sch_sfq.c | 13 +++++++++---- 1 file changed, 9 insertions(+), 4 deletions(-) diff --git a/net/sched/sch_sfq.c b/net/sched/sch_sfq.c index 66dcb18638fea..ed362eefeea9a 100644 --- a/net/sched/sch_sfq.c +++ b/net/sched/sch_sfq.c @@ -608,6 +608,7 @@ static void sfq_perturbation(struct timer_list *t) struct Qdisc *sch = q->sch; spinlock_t *root_lock; siphash_key_t nkey; + int period; get_random_bytes(&nkey, sizeof(nkey)); rcu_read_lock(); @@ -618,8 +619,12 @@ static void sfq_perturbation(struct timer_list *t) sfq_rehash(sch); spin_unlock(root_lock); - if (q->perturb_period) - mod_timer(&q->perturb_timer, jiffies + q->perturb_period); + /* q->perturb_period can change under us from + * sfq_change() and sfq_destroy(). + */ + period = READ_ONCE(q->perturb_period); + if (period) + mod_timer(&q->perturb_timer, jiffies + period); rcu_read_unlock(); } @@ -662,7 +667,7 @@ static int sfq_change(struct Qdisc *sch, struct nlattr *opt) q->quantum = ctl->quantum; q->scaled_quantum = SFQ_ALLOT_SIZE(q->quantum); } - q->perturb_period = ctl->perturb_period * HZ; + WRITE_ONCE(q->perturb_period, ctl->perturb_period * HZ); if (ctl->flows) q->maxflows = min_t(u32, ctl->flows, SFQ_MAX_FLOWS); if (ctl->divisor) { @@ -724,7 +729,7 @@ static void sfq_destroy(struct Qdisc *sch) struct sfq_sched_data *q = qdisc_priv(sch); tcf_block_put(q->block); - q->perturb_period = 0; + WRITE_ONCE(q->perturb_period, 0); del_timer_sync(&q->perturb_timer); sfq_free(q->ht); sfq_free(q->slots); -- 2.39.5