linux-kernel - [PATCH] swap: redirty page if page write fails on swap file

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Message-ID: <516E918B.3050309@redhat.com>
Date:	Wed, 17 Apr 2013 14:11:55 +0200
From:	Jerome Marchand <jmarchan@...hat.com>
To:	"linux-mm@...ck.org" <linux-mm@...ck.org>
CC:	linux-kernel <linux-kernel@...r.kernel.org>,
	Mel Gorman <mgorman@...e.de>
Subject: [PATCH] swap: redirty page if page write fails on swap file


Since commit 62c230b, swap_writepage() calls direct_IO on swap files.
However, in that case page isn't redirtied if I/O fails, and is therefore
handled afterwards as if it has been successfully written to the swap
file, leading to memory corruption when the page is eventually swapped
back in.
This patch sets the page dirty when direct_IO() fails. It fixes a memory
corruption that happened while using swap-over-NFS.

Signed-off-by: Jerome Marchand <jmarchan@...hat.com>
---
 mm/page_io.c |    2 ++
 1 files changed, 2 insertions(+), 0 deletions(-)

diff --git a/mm/page_io.c b/mm/page_io.c
index 78eee32..04ca00d 100644
--- a/mm/page_io.c
+++ b/mm/page_io.c
@@ -222,6 +222,8 @@ int swap_writepage(struct page *page, struct writeback_control *wbc)
 		if (ret == PAGE_SIZE) {
 			count_vm_event(PSWPOUT);
 			ret = 0;
+		} else {
+			set_page_dirty(page);
 		}
 		return ret;
 	}
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/