From nobody Tue Dec 2 02:49:48 2025 Received: from out162-62-57-137.mail.qq.com (out162-62-57-137.mail.qq.com [162.62.57.137]) (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 6CFF7302152; Tue, 18 Nov 2025 07:40:45 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=162.62.57.137 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1763451652; cv=none; b=qHqaraKNi6IsBknujrH52xqFLilKfoBRIPLW03tmSrMCamQ3HjGxRs3qwMtXe/KVFtj4/uaMYgyjZbbO8TVN0WFlOFzsiwKH4lnJNlFeiWsw5R9iiUz89s1fM/0CViHkHSQgyxlYi/VUlzT3m4XOS+/KqyvwuQhRPCNvOpot8CI= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1763451652; c=relaxed/simple; bh=zuw2EycyMzgBaGUcdOzL4LPB0kUmhCIvmtXsD/bqfU8=; h=Message-ID:From:To:Cc:Subject:Date:MIME-Version; b=tuizWzWnAptOhJnpu6NqdPLJXS/tr9+LzuooJpsMgkHtDkv6/Y8+Ae8qiO7NAxtC5HkoTig4M2cTLBmT1H3Ca1izqzSrsxNfXHFWSuDaJJc4ZclTL0pVzdcnWkA0ONL/tGBxUPVCh3w1YIb2yztBrtDwhb8goG4KT9FzAZljOm0= 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=iIPSXVEb; arc=none smtp.client-ip=162.62.57.137 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="iIPSXVEb" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=foxmail.com; s=s201512; t=1763451636; bh=XWMqYs+z3GskzzvBmrAKmgnDeWF6hjh2FG2MoalbIJg=; h=From:To:Cc:Subject:Date; b=iIPSXVEbiyfvH8dmUk+t6QIXfERnqWAuVoBbnEtK2STzJW5/lDxcAfHc7gV9R9I2S tO1TZjCa97n0tMF9iIWCwytHEbupLJdvUFIZB/WrOQj2FSK5dnoDkEQSiwRgnoFA52 Ys6LBeyDdguzrTmeITlEevXbwA1FqlkQznvao2CQ= Received: from meizu-Precision-3660.meizu.com ([14.21.33.152]) by newxmesmtplogicsvrszc50-0.qq.com (NewEsmtp) with SMTP id 9D70BEA7; Tue, 18 Nov 2025 15:39:23 +0800 X-QQ-mid: xmsmtpt1763451563tvholq72r Message-ID: X-QQ-XMAILINFO: Mm8VRyTxzGuAnIMbGpNB7YBJ6dXu8LFvRutC8PX9BL3PSBhQH4wdwNunsZI3EP bQkNBRKBPqJJlTFTJcA0as5jZo7oDGTEdrUohfeVK+cSxg2owbLY2cChKVp94vYeD0exw+sF9Kzd 9XoI15/6sa6NTCIghJ7NdmWKNCDsYcQEXjyqZRbFZYKORi/rQs5KQSOU8rkvE31korAOY6fIRNiZ 4fBsILKOPumNqFaEDef7qTpwQnUfEE8Ijke+gKlZnxijXkoroasehfSPok3vVdt2jAHAfON5Svfq FyHHHie4iBx8QhNbMJQU80rSWrb45/gB1TTAlWqPIcchztB3ziLEhCLDJLBCH6r7mQX3PKmhFySA 50LGgZTSuqocsP/0SaLIrQAq3kAzsCmnO2yGuWIk8QHTEPlSNPWhApDgnUBYuOGaYD0o22Gk9Dnq rTYP2riH0MmHQQ2t/l2j01D/7i15i4gTSn65UW3lsMjPHLttExUJwUzCMtQ8ORG/UGT3ZBpMa/zX 0uWuD3J70fBPWrOCFjlsmqubMdRdGE6jePsAT2gisWE0UC6KW0fFcttcl7KTPPgEFzh1PZ6nK6wv Ad8snX4pZ1PqyIsP0bYvTUxMUszmcDJQPCndRzI44WP17LT25f/ycnntj07GX/QPXijKJLmTDd6d iO/HdFq64xUkbWBHCFlxCPr2do9b19pJEvdW8HS69VRC0xM4eExn5vb5VCAzHtAlcnsBD6qw1FX5 1L1Er1LP6ixXY2JupnbhsKSZ2V9U2z32BGtnAAuVn68yx4NKGjDWYZJujZLBDEMfDOU64dXkQ/Fp OWLSp+KyuFo4sfyOQ5FQ4wqfZkoMEjeXNTckWLFMu0EiNf7w2jCqwQIKL9FyDHm1qiHgd13Rp9S+ KejGJO//dxS3gWvVmthS5tcFjXcGA1X8FUOF1pe6rzC+CxNvddYMG1kb37JrVbcT+K6qSk0IiyMD FRK91ij7sVzwQIrnnK+HarYRxQi1ul2ntYyGyD2DT+BcYMqYART9e7XHn7ko4vmx+8FlA1vSPJWy jYKzVQnU+Igkzhs+5EAAxZ7YdaKL9Sy+vlpsF2utQh8hxzxCovRPCnXRrkbL4poo1YTu9mGsOzEr +P9CCh1GD6lZT8bzVOxbMeMvVgX1TwSoGNypMw+pk/Rwy0k38j2TDQmkuJ5Q== 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] zram: Fix the issue that the write - back limits might overflow Date: Tue, 18 Nov 2025 15:39:20 +0800 X-OQ-MSGID: <20251118073920.2807954-1-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 --- 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 4f2824a..4ecf2e7 100644 --- a/drivers/block/zram/zram_drv.c +++ b/drivers/block/zram/zram_drv.c @@ -562,6 +562,7 @@ 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_read(&zram->init_lock); spin_lock(&zram->wb_limit_lock); zram->bd_wb_limit =3D val; --=20 2.34.1