From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from sender-of-o55.zoho.eu (sender-of-o55.zoho.eu [136.143.169.55]) (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 33ECA3EB7F4 for ; Thu, 19 Mar 2026 15:58:01 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=pass smtp.client-ip=136.143.169.55 ARC-Seal:i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1773935884; cv=pass; b=GElv3ULb0cV1wNgiwEX0RxeGbLTjZlyPBal4LAFNw69L6TvdaymOKyZj0DV7zIx0FV16jOi/RobOZwqRJW+ydBhHiuB63f/ao2HgU4ZhTAAopKLIRYEi3NQwqjSfSXMwMDSHL+Rn95Xjte7wmvKToybOUDxo9APz3mdHAd1EGMw= ARC-Message-Signature:i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1773935884; c=relaxed/simple; bh=Zu6hgfpf9j6l2ALd3UnwnQ3PEI7s5UmGPKtSC/DswLM=; h=From:To:Cc:Subject:Date:Message-Id:MIME-Version; b=o1wEiZTtBtAMn3FaiWlsO+Rss7+/fhvWWHD6LuJS7F268IYsZMXFbI6mHAYHmHyzB2Th2ILMJWaDiZpuX/HU98JaBTDD2lUS8edFMAQqGQZj52RqWZViH3g+FH/XPx236MhXjIXWJqKj+1fN72S8mYqPgyb3Is7YvQuxZVvAs6o= ARC-Authentication-Results:i=2; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=objecting.org; spf=pass smtp.mailfrom=objecting.org; dkim=pass (1024-bit key) header.d=objecting.org header.i=objecting@objecting.org header.b=Br9+Q7sX; arc=pass smtp.client-ip=136.143.169.55 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=objecting.org Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=objecting.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=objecting.org header.i=objecting@objecting.org header.b="Br9+Q7sX" ARC-Seal: i=1; a=rsa-sha256; t=1773935866; cv=none; d=zohomail.eu; s=zohoarc; b=SPq2y71aDBZ5J/5FLM1uM+5uQdrLEHyPaM1jBJha8oL0BwSgwDlGzIcmmLeqbcPnfJZM/LSfsmc3g7vyviFpaMDHJ3NrXiBtqquP4MN24Y7q9ZR69aVLTJASBrSIsmaoO7Y+73xhXUxiKvPnEvEoFzf4kUNggWhQ2eqyQuzwfHI= ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=zohomail.eu; s=zohoarc; t=1773935866; h=Content-Transfer-Encoding:Cc:Cc:Date:Date:From:From:MIME-Version:Message-ID:Subject:Subject:To:To:Message-Id:Reply-To; bh=JI++XvrAXyvmflCj+6eweqyivjRiS4U41ATQdQdKzgI=; b=Gk78sraDQakrwnl5LOsxeGy92KI/l3/eIHjUFyDeKeF8kykGow2H3hNSkGZvD9aHe7aZ6wBEDBXjFcwXc3J4WoknCr3QfLZ44Yf1AMupd6BlO080y3M5OPiFkQqE1TdwEbWXXyGvyzwADMQ4vPTplcf7Efmwas2LaBf2wPRBJK8= ARC-Authentication-Results: i=1; mx.zohomail.eu; dkim=pass header.i=objecting.org; spf=pass smtp.mailfrom=objecting@objecting.org; dmarc=pass header.from= DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; t=1773935866; s=zmail; d=objecting.org; i=objecting@objecting.org; h=From:From:To:To:Cc:Cc:Subject:Subject:Date:Date:Message-Id:Message-Id:MIME-Version:Content-Transfer-Encoding:Reply-To; bh=JI++XvrAXyvmflCj+6eweqyivjRiS4U41ATQdQdKzgI=; b=Br9+Q7sXl646f/z/NKxlgLNHZ9m6jMcQPRBQ+sWSU9bjYuCO15iA0h7ganMuf+HM G3yA7uYmC/6PFk9C84+VKrNX72rQeacadUA9svCeqj9/Uuf12CqZA2VwUGktpi4LaSW JIlUBYD0MtLBbp54Gisjg6twKLZBT/SOr3xUOcKQ= Received: by mx.zoho.eu with SMTPS id 1773935864062723.0335759457625; Thu, 19 Mar 2026 16:57:44 +0100 (CET) From: Josh Law To: sj@kernel.org, akpm@linux-foundation.org Cc: damon@lists.linux.dev, linux-mm@kvack.org, linux-kernel@vger.kernel.org, Josh Law Subject: [PATCH 0/4] mm/damon/sysfs: fix resource leak and NULL pointer dereferences Date: Thu, 19 Mar 2026 15:57:38 +0000 Message-Id: <20260319155742.186627-1-objecting@objecting.org> X-Mailer: git-send-email 2.34.1 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-ZohoMailClient: External This series fixes a memory leak and three NULL pointer dereferences in the DAMON sysfs interface, all in mm/damon/sysfs.c. Patch 1 fixes a damon_ctx leak in damon_sysfs_commit_input() when damon_sysfs_new_test_ctx() fails after param_ctx was already built. Patches 2-4 fix missing contexts->nr checks before dereferencing contexts_arr[0]. A user can trigger these by setting nr_contexts to 0 via sysfs and then issuing commands that assume a context exists: - Patch 2: CLEAR_SCHEMES_TRIED_REGIONS handler in damon_sysfs_handle_cmd() - Patch 3: damon_sysfs_update_schemes_tried_regions(), reached via UPDATE_SCHEMES_TRIED_BYTES and UPDATE_SCHEMES_TRIED_REGIONS - Patch 4: damon_sysfs_repeat_call_fn(), reachable when nr_contexts is set to 0 while DAMON is running Josh Law (4): mm/damon/sysfs: fix param_ctx leak on damon_sysfs_new_test_ctx() failure mm/damon/sysfs: check contexts->nr before clear_schemes_tried_regions mm/damon/sysfs: check contexts->nr in update_schemes_tried_regions mm/damon/sysfs: check contexts->nr in repeat_call_fn mm/damon/sysfs.c | 11 ++++++++++- 1 file changed, 10 insertions(+), 1 deletion(-) -- 2.34.1