From nobody Tue Dec 2 02:49:47 2025 Received: from xmbghk7.mail.qq.com (xmbghk7.mail.qq.com [43.163.128.43]) (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 B7AC4309F1F; Tue, 18 Nov 2025 08:16:01 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=43.163.128.43 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1763453764; cv=none; b=hUL1JYtJd6FZP35zlzI7izzxAevje/S3ven4FZUDT1d0nnA0e9R2NICWBKkFAYdHIFqT35WRBdGzcEHWUfA2UgVz6tinAI8GV3rZCE6Omps8ZuESVyXT9SdWJbR7GxLEAV/czJKVSrpU4aQIvyF7pDPt9GTloIWVzkdiwhKfp1M= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1763453764; c=relaxed/simple; bh=IB9XynbAqeRmsZxpXYSxny1PWyZ4VZELdGdsmNKC90E=; h=Message-ID:From:To:Cc:Subject:Date:MIME-Version; b=E6XZNSxq07D1xdsyg1S9fJfTIWb7Tcrfi4RBqJwykXvMJTglAI5haQ0XcaIXpwuHjqAXVKbCTaHDj1WuPACHzFvpJBB0gaIvFD0wBNlHQN9s3KEeq71hlwaeAmzwNXrmCo5EhZG0zesWXK51ugKmfnzFV5d1dgShLn3VVuaxPXo= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=foxmail.com; spf=pass smtp.mailfrom=foxmail.com; dkim=pass (1024-bit key) header.d=foxmail.com header.i=@foxmail.com header.b=KvWvv9U6; arc=none smtp.client-ip=43.163.128.43 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=foxmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=foxmail.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=foxmail.com header.i=@foxmail.com header.b="KvWvv9U6" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=foxmail.com; s=s201512; t=1763453754; bh=Dgq9GdB+TDgt9ubpi2QIxJvPWQziPEpk10JhrXaywjo=; h=From:To:Cc:Subject:Date; b=KvWvv9U60g+tkussAJeFBfvD7+XPO5vl62rOZVcRlriPXH8fHcZJUomoNvbbW+BUq STcZc2pin+eTwotA6EBBscVTKEIvoJ02dFBEGpszT1RK9SXAITEeNEMyi5GshPeZ0N DXuLaItG7x2WAQr0+AZQUi6VTO7iRNMNcEjkBwbk= Received: from meizu-Precision-3660.meizu.com ([112.91.84.72]) by newxmesmtplogicsvrszb51-0.qq.com (NewEsmtp) with SMTP id 3F3904AA; Tue, 18 Nov 2025 16:15:51 +0800 X-QQ-mid: xmsmtpt1763453751tb4jwdjo9 Message-ID: X-QQ-XMAILINFO: M43YobM9g9iNuzsmc412q5ZBUR8Jmyt41yWOZ/ah1ScleaQUkJu1WSNxFIpu2+ zEQI2tbP2zDTM1Koz8aN0zMJIUcMBpN/da3Vm0RbepEb04IqVomtMs8+FQGNDbwXevM3V4RWZ7+m BfY0Zsy1X2jEquQ67BGYDPFgxYKAEIWHslbEli9DpC8xdWi532MsiDWyV417xXRb8hYzKvaIv0ya 3QT5nlw+NdUUaNA7ZPDUQhn8NcZtx6SQSEsoVXo4A1jGhojFTBaw+zXqf2HqZD4Iczd4NQNkhibD Oos7L7iJHA8tTIJFmlhTAOybxe9l87Uh48QCCQt0sR34lKvN/cg3oiyzS17lvlMQPYtm2oNc+IGI T7pvwqzzKzMuWBMpvK8LyKUD5vyELNP6RdcCwCt3JihUdsdkogJBa/MPE5jR4VuTIEXHw0TBtQ4J mFpEBCfynWxIbSvxUmIyxBQu9ZC8WPesCa7slZcKiD7V0vQdfMRFqLQTd1kw/aDifEEkAUoB0/HW QqhdZdmhZ+N1uam2kQuJpQ9Xjswq6Qhf2iCNe6OCrhQj8PoWoRAQH13Fhw2jB/VvbkVR61lliky1 OMKE5drLNg5OJwE0pnoPmYzV5ZkUJPLX4SCpXwWcY67nKNR1RtCjkXlRMo7c0imFlgfVzMY9Xy/4 N18Rwlg/F9ep5kR/tGMM3pGXT2t9lqmSYJw5UBj1j/vdSjGjqFczoP1dvoSoK1dN40ETtKW1FHzg frLgMC6bMvTLKvjwHXyBh9rHWzFnhuVFuoxZhL5Eg38PTu1thro1rIA2112D6xc1Y+VStaLtb8X9 agZxlT5KIWWvi2hofarshXtwf5FR0lzO6yGyFhtiD6lG3eeV7J4CS+CGBKb7e/SL7Z+uL0q97qWb VHZwDGxklpE4L8vtm6rLHW1Qil2vO39Z5ddURnWAfHNihxrtUzlWc2lCtQJMN6+vHMH/fi4bdg4b yUWUT+IWQBr0bW59qamzPkz9+UJXC6auQnqFIbEWgrReFa0NPNfn9bBIo13YbGKT2DlHyOD6LW71 Aw8er9tEoDNjbdBJFZh8nU+y79mKmUoyN3hdPCn0oTWq2pqzFEhdUxqexwIeAds/SvzPc9H2SMhc NbArsQG59he7ZKwmZ0aityYwMFfBwJrY2RnFBHMsxaO8Dq180xUcDckx7rrnKFEwMfrolz0+/fkz 4Ow8V8dbsUrFH3Uhmajm2X85vN X-QQ-XMRINFO: OD9hHCdaPRBwq3WW+NvGbIU= From: Yuwen Chen To: senozhatsky@chromium.org Cc: akpm@linux-foundation.org, bgeffon@google.com, licayy@outlook.com, linux-block@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, minchan@kernel.org, richardycc@google.com, ywen.chen@foxmail.com Subject: [PATCH v2] zram: Fix the issue that the write - back limits might overflow Date: Tue, 18 Nov 2025 16:15:50 +0800 X-OQ-MSGID: <20251118081550.2809090-1-ywen.chen@foxmail.com> 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: quoted-printable Content-Type: text/plain; charset="utf-8" Since the value of bd_wb_limit is an unsigned number, when the page size is larger than 4 KB, it may cause an out-of-bounds situation. This patch fixes the issue by limiting bd_wb_limit to be an integer multiple of PAGE_SIZE / 4096. Fixes: 1d69a3f8ae77e ("zram: idle writeback fixes and cleanup") Signed-off-by: Yuwen Chen --- Changes in v2: - Rebase the patch to adapt to the latest version. drivers/block/zram/zram_drv.c | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/block/zram/zram_drv.c b/drivers/block/zram/zram_drv.c index 8a13729..5780604 100644 --- a/drivers/block/zram/zram_drv.c +++ b/drivers/block/zram/zram_drv.c @@ -579,6 +579,7 @@ static ssize_t writeback_limit_store(struct device *dev, if (kstrtoull(buf, 10, &val)) return ret; =20 + val =3D val & (~((1UL << (PAGE_SHIFT - 12)) - 1)); down_write(&zram->init_lock); zram->bd_wb_limit =3D val; up_write(&zram->init_lock); --=20 2.34.1