Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932535AbaBUMvW (ORCPT ); Fri, 21 Feb 2014 07:51:22 -0500 Received: from youngberry.canonical.com ([91.189.89.112]:47192 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932518AbaBUMvU (ORCPT ); Fri, 21 Feb 2014 07:51:20 -0500 From: Luis Henriques To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, kernel-team@lists.ubuntu.com Cc: Jan Stancek , Rafael Aquini , Jeff Layton , Trond Myklebust , Andrew Morton , Linus Torvalds , Luis Henriques Subject: [PATCH 3.11 093/121] mm: fix page leak at nfs_symlink() Date: Fri, 21 Feb 2014 12:48:37 +0000 Message-Id: <1392986945-9693-94-git-send-email-luis.henriques@canonical.com> X-Mailer: git-send-email 1.9.0 In-Reply-To: <1392986945-9693-1-git-send-email-luis.henriques@canonical.com> References: <1392986945-9693-1-git-send-email-luis.henriques@canonical.com> X-Extended-Stable: 3.11 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.11.10.5 -stable review patch. If anyone has any objections, please let me know. ------------------ From: Rafael Aquini commit a0b54adda3fe4b4cc6d28f2a9217cd35d1aa888c upstream. Changes in commit a0b8cab3b9b2 ("mm: remove lru parameter from __pagevec_lru_add and remove parts of pagevec API") have introduced a call to add_to_page_cache_lru() which causes a leak in nfs_symlink() as now the page gets an extra refcount that is not dropped. Jan Stancek observed and reported the leak effect while running test8 from Connectathon Testsuite. After several iterations over the test case, which creates several symlinks on a NFS mountpoint, the test system was quickly getting into an out-of-memory scenario. This patch fixes the page leak by dropping that extra refcount add_to_page_cache_lru() is grabbing. Signed-off-by: Jan Stancek Signed-off-by: Rafael Aquini Acked-by: Mel Gorman Acked-by: Rik van Riel Cc: Jeff Layton Cc: Trond Myklebust Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Luis Henriques --- fs/nfs/dir.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/fs/nfs/dir.c b/fs/nfs/dir.c index e474ca2b..7d9261a 100644 --- a/fs/nfs/dir.c +++ b/fs/nfs/dir.c @@ -1813,6 +1813,11 @@ int nfs_symlink(struct inode *dir, struct dentry *dentry, const char *symname) GFP_KERNEL)) { SetPageUptodate(page); unlock_page(page); + /* + * add_to_page_cache_lru() grabs an extra page refcount. + * Drop it here to avoid leaking this page later. + */ + page_cache_release(page); } else __free_page(page); -- 1.9.0 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/