From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 92D13CC6B05 for ; Thu, 2 Apr 2026 05:38:08 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 969A16B0088; Thu, 2 Apr 2026 01:38:07 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 91A276B0089; Thu, 2 Apr 2026 01:38:07 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 856FC6B008A; Thu, 2 Apr 2026 01:38:07 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0013.hostedemail.com [216.40.44.13]) by kanga.kvack.org (Postfix) with ESMTP id 75EA06B0088 for ; Thu, 2 Apr 2026 01:38:07 -0400 (EDT) Received: from smtpin18.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay03.hostedemail.com (Postfix) with ESMTP id 12AE2B9404 for ; Thu, 2 Apr 2026 05:38:07 +0000 (UTC) X-FDA: 84612509814.18.C1AA79C Received: from mail-pf1-f180.google.com (mail-pf1-f180.google.com [209.85.210.180]) by imf10.hostedemail.com (Postfix) with ESMTP id 7C7ACC0008 for ; Thu, 2 Apr 2026 05:38:05 +0000 (UTC) Authentication-Results: imf10.hostedemail.com; dkim=pass header.d=gmail.com header.s=20251104 header.b="T3rOh/9f"; spf=pass (imf10.hostedemail.com: domain of aethernet65535@gmail.com designates 209.85.210.180 as permitted sender) smtp.mailfrom=aethernet65535@gmail.com; dmarc=pass (policy=none) header.from=gmail.com ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1775108285; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-transfer-encoding:content-transfer-encoding: in-reply-to:references:dkim-signature; bh=wpZU7evQNWPDKH6NxwB4xQqMBTVomSBrqVWkgmSAht4=; b=I4f2IZP7+1Up/jv+PjXPgL0DLL12efAUXliURYoBh3bbvQpzda+oSgkAAbvufzULfgVBk4 UCT1GMNtmrr2DAUaq7eG+BdQtBhiO2ES50DWyecRyIDsEqclKDx82GJNKfsBOS4GQkONa3 9JrZk0qBo+Y7HPhcTCwwAUGGiUyizug= ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1775108285; a=rsa-sha256; cv=none; b=N/WvTvPQDD5KPpU6h74rc3UBSoF7Pnznc9kld5DWtKeT8peZ1iVo+vaPSwF90Izj3O4HLr ERBHNUOb5nEx2EzY42HZaUzVtRxiKqS1XK2VWfslJRyK06p6hR0WaN9I+jyRO5k418L/Pr hIwXNlIFn31OVeSQ+1sMBfXsZVIrT7Y= ARC-Authentication-Results: i=1; imf10.hostedemail.com; dkim=pass header.d=gmail.com header.s=20251104 header.b="T3rOh/9f"; spf=pass (imf10.hostedemail.com: domain of aethernet65535@gmail.com designates 209.85.210.180 as permitted sender) smtp.mailfrom=aethernet65535@gmail.com; dmarc=pass (policy=none) header.from=gmail.com Received: by mail-pf1-f180.google.com with SMTP id d2e1a72fcca58-82cdb4ab547so221784b3a.2 for ; Wed, 01 Apr 2026 22:38:05 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20251104; t=1775108284; x=1775713084; darn=kvack.org; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:from:to:cc:subject:date:message-id:reply-to; bh=wpZU7evQNWPDKH6NxwB4xQqMBTVomSBrqVWkgmSAht4=; b=T3rOh/9fm+MAUEb7SWZSAeLr87ftXRoExCzciBrp7cL16bU22zVAwJ316lFpLi4Isv 1/mU7dUvzZybB9K1aiscevjchniaK2uJvPjf2oO85bGHvR92di2M+6FsSHMwoFkS2vQf v9hmkI59Q1VV6ptqVEyKbbo9esanNHaJ7yOtvawLx5EDeDYoRKrARNCwN52doJwY9umC FEGmJJ12XWSnRZv8A5qr8jFPdw46bylhwxgQlNJ3IasWGKwcaGsVXSUhx8aTjBPKn79m K2z8TFWJvQUoyCs9Q3ZJiJtkv8oXN1nQ5GYAcQIfMQaESjgMbGjYywXcejAvEeRnoUt9 FOIg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1775108284; x=1775713084; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:x-gm-gg:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to; bh=wpZU7evQNWPDKH6NxwB4xQqMBTVomSBrqVWkgmSAht4=; b=fQ/tRiE4fu5sazYxV0qJtE34isvtESuBb0BC9hyteS2GYpgjWNFXAKLOS0pIDxUKm8 Gu0yX6ovKKxLAxUWxLSpQ0SpWVZiLJxyp2wEg3AqCWzlVtUZ9yIuXRjVbacd3dhweI5y E4XxN1aoOTxxyGKQjIeH6Ehi8NWiavFIkvPyDq300RwSraZ9toBJz8+xc6TMtTTHOeNI k38A4cmmImyDhxT1uweOS+ywocwontD/kR4oDHDEVRNHMgtfm7bZs9+kSBKJJ+AihOJF CnOCEh9JSwzboN08/ja9YDk6y+jOEnLOdg6OisaxTHzUsh0Ub7tZi2071lM4/f/qebsJ 8z5g== X-Forwarded-Encrypted: i=1; AJvYcCXMrIMI5Ot37sLkTZkGaUJnUPFoMrgDY8dbegoNbN9pQSmGuI9wGpsmJ9SuDX9TzASOGBAiFONvlQ==@kvack.org X-Gm-Message-State: AOJu0Ywooj0Kp7DmBs9xaasXeWXxBijwaqZ0pyUC7vo7XirLW7TeHUOC HSAn+UgfhF16o/m5iDys9itJwgautvoSCLP4Tdw6DJHFZYUnXvCdbRtn X-Gm-Gg: ATEYQzzHkigDToefPTVu2+d2V6IHmOMVH5zmoNZRGTYi1Qdrpl4b+sNBhJTqyFJ1BU8 Cf6Y8bClyKpyee8nyA6dkPT2Byi8HSx69wXxX1AyHo5NJYakCG7nMHVlxX3CzFE88Oqnep3Cm+j Xb829wYUSB9hEXpIZETZJTfLa/n/ct/UQb9eaguHHCL2KY01D52/I6ELS6LXTdcNXvc6RhN6iZz bcRqZdfXSHqGW4RcuU0s5rFwBuBR1Vnm7cEztX3Bn3SVMBzwd+uDxcj6+PwNof5/p98vNh5eMOf 0du39q+YBHd2GGTTgO7GWQZDzg8t37K5lZFpae8lDgfHTpNiD0h+3amCuNykQbBVGk29dKpsZz+ VcUGN9w3CuUfgtf5/VRx3KBbpQQttb8WAG5Z7VsHHETnhSwrOwUlAXKN57ONG7Y1Wfv9aD3KWpf 7gTJrRsBP+l99GMGGs7RiRvEbAtnhuLkVLyEhIXC9NVtdhpU2bncU= X-Received: by 2002:a05:6a00:2e94:b0:823:12cb:f5d1 with SMTP id d2e1a72fcca58-82ce88ea8ebmr6525320b3a.6.1775108284208; Wed, 01 Apr 2026 22:38:04 -0700 (PDT) Received: from celestia.taila51cc2.ts.net ([2402:1980:898b:301c:d085:a35:99e7:ffec]) by smtp.gmail.com with ESMTPSA id d2e1a72fcca58-82cf9ca1f28sm1758569b3a.57.2026.04.01.22.38.01 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 01 Apr 2026 22:38:03 -0700 (PDT) From: Liew Rui Yan To: sj@kernel.org Cc: damon@lists.linux.dev, linux-mm@kvack.org, Liew Rui Yan Subject: [PATCH v2] mm/damon: validate min_region_size to be power of 2 Date: Thu, 2 Apr 2026 13:37:56 +0800 Message-ID: <20260402053756.26606-1-aethernet65535@gmail.com> X-Mailer: git-send-email 2.53.0 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Rspamd-Queue-Id: 7C7ACC0008 X-Stat-Signature: 3bmitg64q4dhu93hmygekk53egeadzwd X-Rspam-User: X-Rspamd-Server: rspam07 X-HE-Tag: 1775108285-634093 X-HE-Meta: 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 EU2FY+hW 8g2pt/z3jS76BqcpAqPfw6Ok1FR9rqjGqjPxPvcaz82Ze28EpcH+yzFsLaJ2S1a6hHRWvl/98Q4GWv2EvP63udosKdABRdd4SISXn Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: Problem ======= damon_commit_ctx() checks if 'min_region_sz' is a power of 2. But if it is not, kdamond will terminate unexpectedly due to the user's invalid input. Solution ======== Add the same check to damon_{lru_sort, reclaim}_apply_parameters(), but return -EINVAL immediately. This is to prevent user's invalid input causing kdamond to terminate unexpectedly. This patch is a follow-up to the discussion in [1], where we agreed that the validation should be done on min_region_sz rather than addr_unit. [1] https://lore.kernel.org/20260330233343.4083-1-sj@kernel.org Signed-off-by: Liew Rui Yan --- Changes from v1: - Fix memory leak issue. - Link to v1: https://lore.kernel.org/20260331073231.30060-1-aethernet65535@gmail.com mm/damon/lru_sort.c | 5 +++++ mm/damon/reclaim.c | 5 +++++ 2 files changed, 10 insertions(+) diff --git a/mm/damon/lru_sort.c b/mm/damon/lru_sort.c index 554559d72976..3fd176ef9d9c 100644 --- a/mm/damon/lru_sort.c +++ b/mm/damon/lru_sort.c @@ -294,6 +294,11 @@ static int damon_lru_sort_apply_parameters(void) param_ctx->addr_unit = addr_unit; param_ctx->min_region_sz = max(DAMON_MIN_REGION_SZ / addr_unit, 1); + if (!is_power_of_2(param_ctx->min_region_sz)) { + err = -EINVAL; + goto out; + } + if (!damon_lru_sort_mon_attrs.sample_interval) { err = -EINVAL; goto out; diff --git a/mm/damon/reclaim.c b/mm/damon/reclaim.c index 86da14778658..2747eef5919d 100644 --- a/mm/damon/reclaim.c +++ b/mm/damon/reclaim.c @@ -204,6 +204,11 @@ static int damon_reclaim_apply_parameters(void) param_ctx->addr_unit = addr_unit; param_ctx->min_region_sz = max(DAMON_MIN_REGION_SZ / addr_unit, 1); + if (!is_power_of_2(param_ctx->min_region_sz)) { + err = -EINVAL; + goto out; + } + if (!damon_reclaim_mon_attrs.aggr_interval) { err = -EINVAL; goto out; -- 2.53.0