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 D60D3F9EDDB for ; Wed, 22 Apr 2026 14:41:20 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 4CB306B0088; Wed, 22 Apr 2026 10:41:20 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 47C2F6B008A; Wed, 22 Apr 2026 10:41:20 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 3920F6B008C; Wed, 22 Apr 2026 10:41:20 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0016.hostedemail.com [216.40.44.16]) by kanga.kvack.org (Postfix) with ESMTP id 253356B0088 for ; Wed, 22 Apr 2026 10:41:20 -0400 (EDT) Received: from smtpin09.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay10.hostedemail.com (Postfix) with ESMTP id A2C15C0C41 for ; Wed, 22 Apr 2026 14:41:19 +0000 (UTC) X-FDA: 84686454678.09.BC16255 Received: from sea.source.kernel.org (sea.source.kernel.org [172.234.252.31]) by imf07.hostedemail.com (Postfix) with ESMTP id 0313A4000B for ; Wed, 22 Apr 2026 14:41:17 +0000 (UTC) Authentication-Results: imf07.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20201202 header.b="Uje//+Uo"; spf=pass (imf07.hostedemail.com: domain of sj@kernel.org designates 172.234.252.31 as permitted sender) smtp.mailfrom=sj@kernel.org; dmarc=pass (policy=quarantine) header.from=kernel.org ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1776868878; 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:in-reply-to:references:references:dkim-signature; bh=SGlQc+AqP9diL1HJyH6+HmRQnGbn5ga6UORt7akFb0g=; b=8B5PI4eRMVvsaN/GtYsuEayEZ0jxNw4vinGicwhDkJYZsAW0v4I/IVDndJOpShCRBdn0N2 5T3JklKUaqj0/GKLCLIULRal+4sXoUQqoHi5PD9QX8wvfBqYGa01eywvYR/RG3U1ImI3BR n3Ah814DQXFWPmzimLlTpQApa/kIAIg= ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1776868878; a=rsa-sha256; cv=none; b=DjndkBUrxkLchUXfMxZPy9NVCbySkwDqdPFRgFPkUwaVWe3uKC2s471TAzBoF/3hh199x6 9GP7UAOaTTBETFUHJW2kCBhycmkk1n0/mNYS/3qaOcc9Ax/GuhxN/xN0WuUAs4h7Z41yFC p5tU/uiyI/JoViTM3f10MIo5gTN/x6U= ARC-Authentication-Results: i=1; imf07.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20201202 header.b="Uje//+Uo"; spf=pass (imf07.hostedemail.com: domain of sj@kernel.org designates 172.234.252.31 as permitted sender) smtp.mailfrom=sj@kernel.org; dmarc=pass (policy=quarantine) header.from=kernel.org Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by sea.source.kernel.org (Postfix) with ESMTP id E06C943EAD; Wed, 22 Apr 2026 14:41:16 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 7F4D0C19425; Wed, 22 Apr 2026 14:41:16 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1776868876; bh=dPh+28e9o3rFcTZ19LGrpIKOeKqHRgIxt9m1cNTW0OI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Uje//+UoTKmRJ5EoGDyItpPUxlbew9QtwD5e5jcyMBDhgk5QI6JF5kJG/fdtkc32F Vva5ikvKVmSmlKRS8JSCBlRVI0DuNKbeneEvZyXp3OrTg2oVeAZ0um3pFGZuPIgvXe uYxLOIRnwk2IqagrOgdEoAn3nLknWU+aov5+Y3dFoWx/fFTMQFGMl69p9Is/r6zAGR Fj6lufcUj7ONPb/Jd2qUvGcxFQkKCVWfWY9ZODGbzszJzOQHt6zv2v9P4c1zSi4CIb 9YeHwGQKivViLtoodqTQy5EpcQh/9FbHDcMTU497CxLTtBlIKgqLWEkFd5aGL4tC6O vihd6xExMyVHQ== From: SeongJae Park To: SeongJae Park Cc: "# 6 . 16 . x" , Andrew Morton , damon@lists.linux.dev, linux-kernel@vger.kernel.org, linux-mm@kvack.org, Junxi Qian Subject: Re: [RFC PATCH 0/2] mm/damon/sysfs-schemes: fix use-after-free for [memcg_]path Date: Wed, 22 Apr 2026 07:40:59 -0700 Message-ID: <20260422144059.72000-1-sj@kernel.org> X-Mailer: git-send-email 2.47.3 In-Reply-To: <20260422143503.71357-1-sj@kernel.org> References: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Stat-Signature: qgscsmjeqwmdjp19os6ctzeekdjud6gx X-Rspam-User: X-Rspamd-Queue-Id: 0313A4000B X-Rspamd-Server: rspam05 X-HE-Tag: 1776868877-545173 X-HE-Meta: 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 bcCT0zY3 BU1PcHlFA0P3x7oXoCEj/L3fQdg9XctisGAziUA1HLZh0jpvzegoB8f2VlWKu+KPTq1ET7pLScUplSWyG1rpRhxNaXvIUzrT8wUENdv1CLECNJJQxxX6lauHZlQNAx6O6elAKsb3dLqNRiZqTn4E1SksIEpTwXQemP4yfM9R3++oxmQ2OOwCDUXlpTtox+LbSekLxSTuevZnv7G/APKIqOofAe/gLdiriSyr9m+HXj3n9hRHdJ3U8TeQlv6nF4AB/ax3vmsCxISRk8cJUF0HOudFlqMSHb6md1+vLs9XP6RpKbmRdw2HKlEHBgmA0JJCXvxj+ Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Wed, 22 Apr 2026 07:34:59 -0700 SeongJae Park wrote: > Reads of 'path' and 'memcg_path' files in DAMON sysfs interface could > race with their writes, results in use-after-free. Fix those. Forgot adding change log, sorry. Changes from v2 - v2: https://lore.kernel.org/20260420125405.362137-1-qjx1298677004@gmail.com - Split patch for individual fixes commits. - Hand-off authorship to SJ, give Co-developed-by: to Junxi. - Use mutex_trylock() instead of mutex_lock(). - Add RFC tag for Sashiko review round. - Wordsmith commit messages. Changes from v1 - v1: https://lore.kernel.org/20260420085332.178473-1-qjx1298677004@gmail.com - Protect not only user-writes but also user-reads. Thanks, SJ > > SeongJae Park (2): > mm/damon/sysfs-schemes: protect memcg_path kfree() with > damon_sysfs_lock > mm/damon/sysfs-schemes: protect path kfree() with damon_sysfs_lock > > mm/damon/sysfs-schemes.c | 24 ++++++++++++++++++++++-- > 1 file changed, 22 insertions(+), 2 deletions(-) > > > base-commit: 0d45806f3a75bf53e59475b0e56be324f650ab09 > -- > 2.47.3 Sent using hkml (https://github.com/sjp38/hackermail)