From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wi0-f169.google.com (mail-wi0-f169.google.com [209.85.212.169]) by kanga.kvack.org (Postfix) with ESMTP id 0C5006B0071 for ; Mon, 4 May 2015 17:17:12 -0400 (EDT) Received: by widdi4 with SMTP id di4so124150557wid.0 for ; Mon, 04 May 2015 14:17:11 -0700 (PDT) Received: from mail-wi0-f169.google.com (mail-wi0-f169.google.com. [209.85.212.169]) by mx.google.com with ESMTPS id pa2si24560044wjb.137.2015.05.04.14.17.09 for (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Mon, 04 May 2015 14:17:10 -0700 (PDT) Received: by wizk4 with SMTP id k4so136608654wiz.1 for ; Mon, 04 May 2015 14:17:09 -0700 (PDT) From: Anisse Astier Subject: [PATCH v2 3/4] PM / Hibernate: fix SANITIZE_FREED_PAGES Date: Mon, 4 May 2015 23:16:57 +0200 Message-Id: <1430774218-5311-4-git-send-email-anisse@astier.eu> In-Reply-To: <1430774218-5311-1-git-send-email-anisse@astier.eu> References: <1430774218-5311-1-git-send-email-anisse@astier.eu> Sender: owner-linux-mm@kvack.org List-ID: Cc: Anisse Astier , Andrew Morton , Mel Gorman , "Kirill A. Shutemov" , David Rientjes , Alan Cox , Linus Torvalds , Peter Zijlstra , PaX Team , Brad Spengler , Kees Cook , Andi Kleen , linux-mm@kvack.org, linux-kernel@vger.kernel.org SANITIZE_FREED_PAGES feature relies on having all pages going through the free_pages_prepare path in order to be cleared before being used. In the hibernate use case, pages will automagically appear in the system without being cleared. This fix will make sure free pages are cleared on resume. Signed-off-by: Anisse Astier --- kernel/power/hibernate.c | 7 ++++++- kernel/power/power.h | 4 ++++ kernel/power/snapshot.c | 21 +++++++++++++++++++++ 3 files changed, 31 insertions(+), 1 deletion(-) diff --git a/kernel/power/hibernate.c b/kernel/power/hibernate.c index 2329daa..3193b9a 100644 --- a/kernel/power/hibernate.c +++ b/kernel/power/hibernate.c @@ -305,9 +305,14 @@ static int create_image(int platform_mode) error); /* Restore control flow magically appears here */ restore_processor_state(); - if (!in_suspend) + if (!in_suspend) { events_check_enabled = false; +#ifdef CONFIG_SANITIZE_FREED_PAGES + clear_free_pages(); + printk(KERN_INFO "PM: free pages cleared after restore\n"); +#endif + } platform_leave(platform_mode); Power_up: diff --git a/kernel/power/power.h b/kernel/power/power.h index ce9b832..26b2101 100644 --- a/kernel/power/power.h +++ b/kernel/power/power.h @@ -92,6 +92,10 @@ extern int create_basic_memory_bitmaps(void); extern void free_basic_memory_bitmaps(void); extern int hibernate_preallocate_memory(void); +#ifdef CONFIG_SANITIZE_FREED_PAGES +extern void clear_free_pages(void); +#endif + /** * Auxiliary structure used for reading the snapshot image data and * metadata from and writing them to the list of page backup entries diff --git a/kernel/power/snapshot.c b/kernel/power/snapshot.c index 5235dd4..673ade1 100644 --- a/kernel/power/snapshot.c +++ b/kernel/power/snapshot.c @@ -1032,6 +1032,27 @@ void free_basic_memory_bitmaps(void) pr_debug("PM: Basic memory bitmaps freed\n"); } +#ifdef CONFIG_SANITIZE_FREED_PAGES +void clear_free_pages(void) +{ + struct memory_bitmap *bm = free_pages_map; + unsigned long pfn; + + if (WARN_ON(!(free_pages_map))) + return; + + memory_bm_position_reset(bm); + pfn = memory_bm_next_pfn(bm); + while (pfn != BM_END_OF_MAP) { + if (pfn_valid(pfn)) + clear_highpage(pfn_to_page(pfn)); + + pfn = memory_bm_next_pfn(bm); + } + memory_bm_position_reset(bm); +} +#endif /* SANITIZE_FREED_PAGES */ + /** * snapshot_additional_pages - estimate the number of additional pages * be needed for setting up the suspend image data structures for given -- 1.9.3 -- 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