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 5DA4B10BA426 for ; Fri, 27 Mar 2026 06:26:38 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id C79396B0098; Fri, 27 Mar 2026 02:26:37 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id C29CE6B00AE; Fri, 27 Mar 2026 02:26:37 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id B67BB6B00AF; Fri, 27 Mar 2026 02:26:37 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0010.hostedemail.com [216.40.44.10]) by kanga.kvack.org (Postfix) with ESMTP id A89336B0098 for ; Fri, 27 Mar 2026 02:26:37 -0400 (EDT) Received: from smtpin04.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay08.hostedemail.com (Postfix) with ESMTP id 503BD140FE6 for ; Fri, 27 Mar 2026 06:26:37 +0000 (UTC) X-FDA: 84590859234.04.8806736 Received: from mail-pj1-f49.google.com (mail-pj1-f49.google.com [209.85.216.49]) by imf18.hostedemail.com (Postfix) with ESMTP id 87CD81C0006 for ; Fri, 27 Mar 2026 06:26:35 +0000 (UTC) Authentication-Results: imf18.hostedemail.com; dkim=pass header.d=gmail.com header.s=20251104 header.b="l46PY/4M"; spf=pass (imf18.hostedemail.com: domain of aethernet65535@gmail.com designates 209.85.216.49 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=1774592795; 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=UfeL5siJ6xe6Uo5hQEXOS6s+/4tbof4Lxqs1l9wyAMQ=; b=b+i7OsLAbj1d0nKofY86N0vkRzihFN8EkOdgGdBx1H/ozvXHJv3I6LegZn7r7fed++tERV KOgL3MiGP1EBUf4vwRtLS+1DVeb+6+jKfCmq7MncIcq/66uk2aj5YIi7Tewmitz0ajnvYq BKnttVu3/sQfgzr0L3E3wPn55AUc51U= ARC-Authentication-Results: i=1; imf18.hostedemail.com; dkim=pass header.d=gmail.com header.s=20251104 header.b="l46PY/4M"; spf=pass (imf18.hostedemail.com: domain of aethernet65535@gmail.com designates 209.85.216.49 as permitted sender) smtp.mailfrom=aethernet65535@gmail.com; dmarc=pass (policy=none) header.from=gmail.com ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1774592795; a=rsa-sha256; cv=none; b=wnSkSXVdILO3GgbG+/T9plisdU6Dp3bf8+GA0oZcoyE5qro0PmSdao/0BMjsDNHd7HPz3v L5pX1SYEz1HEY1PECE0yONMgPtIrif0pfPkHKW8SOsxpZTsgUKEQ0ekmSJkj8+NbzDauKl tnKeodK10T4LAefPwA7gAUBwz85sYq8= Received: by mail-pj1-f49.google.com with SMTP id 98e67ed59e1d1-354bc7c2c46so1104015a91.0 for ; Thu, 26 Mar 2026 23:26:35 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20251104; t=1774592794; x=1775197594; 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=UfeL5siJ6xe6Uo5hQEXOS6s+/4tbof4Lxqs1l9wyAMQ=; b=l46PY/4MyGHQv9UmyWiBxtSzobpYVwhScpfbeiF0S2uMSnt2WyWF9eNb51kLr3yPGd KpAH7oksSssN8O9eUs+EFIVB0gqhnDmoJ1IhmJyq79FpaSauhMCjr0SsRXtqJ+++UrHq 71dUnEKG8kX2PoKkuXCBZFm6gZEH3rYsT3k80MY6VrhNQUf91NIt15R2Mky1MkTd3hB+ f1t2R7QvJ3AWKZU866ZOd7jNX0PAMQOIlCwSKhgF82FblMzLwnnuA/Nixt/JvZyCCAKH yUeNF3LQN/BiyLgHYQGR10NXRON6BjhJfnxQYlbZLrCG8wB/aEzdY7uIlTIs0Kgu/flh InBw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1774592794; x=1775197594; 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=UfeL5siJ6xe6Uo5hQEXOS6s+/4tbof4Lxqs1l9wyAMQ=; b=g+nU4aMlrzvcge6/rpuBFP1BGMOWdvTR4csSgYJuuWrFW3q6l3wvuM//ADlwO+x3KH +sJk0mJrOMxpW2XC3lJWwkI7oxUbbUnCkycruTpv08UfqxZbxVnoInsKItSG1jA0085I 00+WNz3nY9ac1+QUBESnE6ZJWQGT+fx41p1cX5xnaiJZz9TYGqjBxBR2OQhkHpO0GuWZ ndtzRitrcF7b0G9KaaWoFX2IlHIk8dX4x6kN5JPATcj0GeQiV4SDvqizzLeR9VnVcn0E kvuO/azm5hxKVYy42oR4SWtuK5B/ZKIQumdnIV+N/HgYesf+nkH7hPYRkPHQqN5y3X7m 6P7g== X-Forwarded-Encrypted: i=1; AJvYcCUL436v2SS9TFYtRLGCoCFNBBqKprXitaFb0g9bAt7lrjqrsY5bUtrlW/D6cV9+0gLnwerGN4XGhg==@kvack.org X-Gm-Message-State: AOJu0YycMPvBJIRAkyBPCZqGISwKQmp4bmwsxqVxviFV2ta0c1IztXqu R/hg1FCLHFh4zHK+KqLpslNwpopZ9CExa1rSDZp1mN/gzXInQeWpRwaX X-Gm-Gg: ATEYQzyPIyPyNeg+8x67G0WdUVwo2uqETIQ6OYYeEGqi+2tTD1GS1blyBFNBeJ0ggeK e05krBA3TUyDs7PfoEU4fQCM8AOszYljCeo8YtPgVinLlyOzdqSVbjbn9A5q1IgnyZWPUhhPial EQLENQruoId1XwaRD2aeNEryMM+7d9W/j6gTdBwqwg2AN1IIgHZk78yiP26rJnvC6RwLYt99MCg gXHDlMZoM2zxM7d8ESrYXdKwGELQdXmPTKjFO0zsZpXTFGO7DxfhbPedx32DCW3KmlPzsDIprUZ wY3ZxWZGQUAVpEJLFLhjhvZX8ylSeD5wugy7OvxamUDKuhKW8Z7ZnJ1eW2zIcjRyKpwVqeJHuVP Vlo9aJdLgMrJAjc/xdgTeqa4SK40PJ+1jXSmGW777AcfrcThD+zcTwUEwq2+8T6J+4xVYk2OQwq 2XqhjvhH3Cl6E6b7eznD48Vyy3eImUqSb21rGg5w== X-Received: by 2002:a17:90b:3ec5:b0:359:9016:1e72 with SMTP id 98e67ed59e1d1-35c30076ea8mr1429306a91.19.1774592794262; Thu, 26 Mar 2026 23:26:34 -0700 (PDT) Received: from celestia ([2402:1980:898b:301c:d085:a35:99e7:ffec]) by smtp.gmail.com with ESMTPSA id 98e67ed59e1d1-35c22a4ee7esm3533241a91.1.2026.03.26.23.26.31 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 26 Mar 2026 23:26:33 -0700 (PDT) From: Liew Rui Yan To: sj@kernel.org Cc: damon@lists.linux.dev, linux-mm@kvack.org, Liew Rui Yan Subject: [PATCH] mm/damon: validate addr_unit to be power of 2 Date: Fri, 27 Mar 2026 14:26:27 +0800 Message-ID: <20260327062627.66426-1-aethernet65535@gmail.com> X-Mailer: git-send-email 2.53.0 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Rspamd-Queue-Id: 87CD81C0006 X-Stat-Signature: d5mjtb1g7eijhi1w39i8u6guopixnk74 X-Rspam-User: X-Rspamd-Server: rspam08 X-HE-Tag: 1774592795-833932 X-HE-Meta: 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 LevE4qJv wP1QrDN/Cb4XuqLx2JAmLxb/7N4D04CWHgnFSCN5LuKrWGsiAMo+bR62vVXij2A426h7JwGkiyq8BhHV0zdXuAATdLHPwMS7+WQe1LzfmJ9gkL7UMuBphgN1qK5VaGW4zbF/ZKqVyR2PX/RzO2c19ZXiBahV3TY7L5tL1mzBHadza6d2EPxkBxUsbq5k5+1ZtMuGCAtwyVeSqx508Pq3w/NPNX3Fwp+ZrQMNYCUDkETm0aO2hB/lqL7WhNIFju+Kk8UiEZWRI0Fw+/JlRx0nwKgfv9jvfH85/9+JAIyPlawjf8ZqJIzeZt0RwnRIOTULhw+7TinGjAmGbMbm3nlH7x7+tCp0p3S/KZqPJeKRzysfqDetZjAL9u2LXWF5lcD1rS5zF/5Th7gwM202Mm4aksy3RoOtwg3Pu+rDuOJiA3iCmCZ8ZdAbbtNZkfaMUrHxzJPTINwEyaFh2so03sMWkGF9V/g9Lnp/eP5ekSPQMGf+lk74= Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: Problem ======= The 'addr_unit' must be a power of 2 for correct address alignment calculations. Previously, writing a non-power-of-2 value (e.g., addr_unit=3) would be accepted by the sysfs store callback, but cause kdamond to exit unexpectedly during parameter application, failing silently without returning an error to userspace. Solution ======== Add an is_power_of_2() check in damon_commit_ctx() to reject invalid inputs immediately with -EINVAL. When damon_commit_ctx() fails, the kdamond thread terminates as designed. The issue is found by sashiko [1]. [1] https://lore.kernel.org/20260325025317.86571-1-sj@kernel.org Signed-off-by: Liew Rui Yan --- mm/damon/core.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/mm/damon/core.c b/mm/damon/core.c index db6c67e52d2b..6bad85a47a79 100644 --- a/mm/damon/core.c +++ b/mm/damon/core.c @@ -1330,6 +1330,8 @@ int damon_commit_ctx(struct damon_ctx *dst, struct damon_ctx *src) dst->maybe_corrupted = true; if (!is_power_of_2(src->min_region_sz)) return -EINVAL; + if (!src->addr_unit || !is_power_of_2(src->addr_unit)) + return -EINVAL; err = damon_commit_schemes(dst, src); if (err) -- 2.53.0