From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wm0-f70.google.com (mail-wm0-f70.google.com [74.125.82.70]) by kanga.kvack.org (Postfix) with ESMTP id 499F16B025E for ; Wed, 1 Feb 2017 04:27:18 -0500 (EST) Received: by mail-wm0-f70.google.com with SMTP id q124so4064024wmg.2 for ; Wed, 01 Feb 2017 01:27:18 -0800 (PST) Received: from mail-wm0-f67.google.com (mail-wm0-f67.google.com. [74.125.82.67]) by mx.google.com with ESMTPS id 186si20556502wmx.129.2017.02.01.01.27.17 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Wed, 01 Feb 2017 01:27:17 -0800 (PST) Received: by mail-wm0-f67.google.com with SMTP id v77so4462539wmv.0 for ; Wed, 01 Feb 2017 01:27:17 -0800 (PST) From: Michal Hocko Subject: [PATCH 2/3] mm, fs: check for fatal signals in do_generic_file_read Date: Wed, 1 Feb 2017 10:27:05 +0100 Message-Id: <20170201092706.9966-3-mhocko@kernel.org> In-Reply-To: <20170201092706.9966-1-mhocko@kernel.org> References: <20170201092706.9966-1-mhocko@kernel.org> Sender: owner-linux-mm@kvack.org List-ID: To: Andrew Morton Cc: Christoph Hellwig , Tetsuo Handa , Al Viro , linux-mm@kvack.org, linux-fsdevel@vger.kernel.org, LKML , Michal Hocko From: Michal Hocko do_generic_file_read can be told to perform a large request from userspace. If the system is under OOM and the reading task is the OOM victim then it has an access to memory reserves and finishing the full request can lead to the full memory depletion which is dangerous. Make sure we rather go with a short read and allow the killed task to terminate. Cc: stable Signed-off-by: Michal Hocko --- mm/filemap.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/mm/filemap.c b/mm/filemap.c index 14bddd0d7fa4..2ba46f410c7c 100644 --- a/mm/filemap.c +++ b/mm/filemap.c @@ -1797,6 +1797,11 @@ static ssize_t do_generic_file_read(struct file *filp, loff_t *ppos, cond_resched(); find_page: + if (fatal_signal_pending(current)) { + error = -EINTR; + goto out; + } + page = find_get_page(mapping, index); if (!page) { page_cache_sync_readahead(mapping, -- 2.11.0 -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org