Home » Mailing list archives » linux-kernel » 2008 » January » 14

[PATCH] [29/31] CPA: Add a BUG_ON checking for someone setting the kernel text NX

!MAILaRCHIVE_VOTE_RePLACE
Previous message: [thread] [date] [author]
Next message: [thread] [date] [author]
[view in full thread]
From: Andi Kleen <ak@...>
To: <linux-kernel@...>, <jbeulich@...>, <mingo@...>, <tglx@...>
Subject: [PATCH] [29/31] CPA: Add a BUG_ON checking for someone setting the kernel text NX
Date: Monday, January 14, 2008 - 6:17 pm

Someone setting NX on the kernel text tends to result in nasty failures
and triple faults, so BUG_ON early for that.

Does not cover __inittext.

Signed-off-by: Andi Kleen <ak@suse.de>

---
 arch/x86/mm/pageattr_32.c |    8 ++++++++
 1 file changed, 8 insertions(+)

Index: linux/arch/x86/mm/pageattr_32.c
===================================================================
--- linux.orig/arch/x86/mm/pageattr_32.c
+++ linux/arch/x86/mm/pageattr_32.c
@@ -242,6 +242,14 @@ __change_page_attr(struct page *page, pg
 	BUG_ON(PageLRU(kpte_page));
 	BUG_ON(PageCompound(kpte_page));
 
+	/*
+	 * Better fail early if someone sets the kernel text to NX.
+	 * Does not cover __inittext
+	 */
+	BUG_ON(address >= (unsigned long)&_text &&
+		address < (unsigned long)&_etext &&
+	       (pgprot_val(prot) & _PAGE_NX));
+
 	set_tlb_flush(address, cache_attr_changed(*kpte, prot, level),
 			level < 3);
 
--
Previous message: [thread] [date] [author]
Next message: [thread] [date] [author]
Messages in current thread:
[PATCH] [0/31] Great change_page_attr patch series v2, Andi Kleen, (Mon Jan 14, 6:16 pm)
Re: [PATCH] [0/31] Great change_page_attr patch series v2, Jan Beulich, (Tue Jan 15, 5:11 am)
Re: [PATCH] [0/31] Great change_page_attr patch series v2, Andi Kleen, (Tue Jan 15, 6:06 am)
Re: [PATCH] [0/31] Great change_page_attr patch series v2, Jan Beulich, (Tue Jan 15, 7:55 am)
Re: [PATCH] [0/31] Great change_page_attr patch series v2, Andi Kleen, (Tue Jan 15, 8:43 am)
[PATCH] [31/31] Clean up pte_exec, Andi Kleen, (Mon Jan 14, 6:17 pm)
[PATCH] [30/31] Remove set_kernel_exec, Andi Kleen, (Mon Jan 14, 6:17 pm)
[PATCH] [29/31] CPA: Add a BUG_ON checking for someone setti..., Andi Kleen, (Mon Jan 14, 6:17 pm)
[PATCH] [28/31] CPA: Make kernel_text test match boot mappin..., Andi Kleen, (Mon Jan 14, 6:17 pm)
[PATCH] [27/31] CPA: Change comments of external interfaces ..., Andi Kleen, (Mon Jan 14, 6:17 pm)
Re: [PATCH] [27/31] CPA: Change comments of external interfa..., Randy Dunlap, (Mon Jan 14, 6:50 pm)
Re: [PATCH] [27/31] CPA: Change comments of external interfa..., Andi Kleen, (Mon Jan 14, 8:49 pm)
[PATCH] [26/31] CPA: Fix reference counting when changing al..., Andi Kleen, (Mon Jan 14, 6:16 pm)
Re: [PATCH] [26/31] CPA: Fix reference counting when changin..., Jan Beulich, (Tue Jan 15, 5:05 am)
Re: [PATCH] [26/31] CPA: Fix reference counting when changin..., Andi Kleen, (Tue Jan 15, 6:04 am)
Re: [PATCH] [26/31] CPA: Fix reference counting when changin..., Jan Beulich, (Tue Jan 15, 8:00 am)
[PATCH] [25/31] CPA: Always do full TLB flush when splitting..., Andi Kleen, (Mon Jan 14, 6:16 pm)
[PATCH] [24/31] CPA: Only unmap kernel init pages in text ma..., Andi Kleen, (Mon Jan 14, 6:16 pm)
[PATCH] [23/31] CPA: Remove unnecessary masking of address, Andi Kleen, (Mon Jan 14, 6:16 pm)
[PATCH] [22/31] CPA: Only queue actually unused page table p..., Andi Kleen, (Mon Jan 14, 6:16 pm)
[PATCH] [20/31] CPA: Fix inaccurate comments in 64bit change..., Andi Kleen, (Mon Jan 14, 6:16 pm)
[PATCH] [21/31] CPA: Dump pagetable when inconsistency is de..., Andi Kleen, (Mon Jan 14, 6:16 pm)
[PATCH] [19/31] CPA: Limit cache flushing to pages that real..., Andi Kleen, (Mon Jan 14, 6:16 pm)
Re: [PATCH] [19/31] CPA: Limit cache flushing to pages that ..., Jan Beulich, (Tue Jan 15, 4:46 am)
[PATCH] [18/31] CPA: Make change_page_attr() more robust aga..., Andi Kleen, (Mon Jan 14, 6:16 pm)
[PATCH] [15/31] CPA: Don't flush the caches when the CPU sup..., Andi Kleen, (Mon Jan 14, 6:16 pm)
[PATCH] [17/31] CPA: Reorder TLB / cache flushes to follow I..., Andi Kleen, (Mon Jan 14, 6:16 pm)
[PATCH] [12/31] CPA: CLFLUSH support in change_page_attr(), Andi Kleen, (Mon Jan 14, 6:16 pm)
Re: [PATCH] [12/31] CPA: CLFLUSH support in change_page_attr(), Jan Beulich, (Tue Jan 15, 4:40 am)
Re: [PATCH] [12/31] CPA: CLFLUSH support in change_page_attr(), Andi Kleen, (Tue Jan 15, 5:57 am)
[PATCH] [16/31] CPA: Use wbinvd() macro instead of inline as..., Andi Kleen, (Mon Jan 14, 6:16 pm)
[PATCH] [14/31] CPA: Use page granuality TLB flushing in cha..., Andi Kleen, (Mon Jan 14, 6:16 pm)
[PATCH] [13/31] CPA: Use macros to modify the PG_arch_1 page..., Andi Kleen, (Mon Jan 14, 6:16 pm)
Re: [PATCH] [13/31] CPA: Use macros to modify the PG_arch_1 ..., Harvey Harrison, (Tue Jan 15, 5:29 am)
Re: [PATCH] [13/31] CPA: Use macros to modify the PG_arch_1 ..., Andi Kleen, (Tue Jan 15, 6:06 am)
Re: [PATCH] [13/31] CPA: Use macros to modify the PG_arch_1 ..., Harvey Harrison, (Tue Jan 15, 6:15 am)
Re: [PATCH] [13/31] CPA: Use macros to modify the PG_arch_1 ..., Andi Kleen, (Tue Jan 15, 6:25 am)
[PATCH] [11/31] CPA: Change 32bit back to init_mm semaphore ..., Andi Kleen, (Mon Jan 14, 6:16 pm)
[PATCH] [10/31] CPA: Change kernel_map_pages to not use c_p_..., Andi Kleen, (Mon Jan 14, 6:16 pm)
[PATCH] [9/31] CPA: Add simple self test at boot, Andi Kleen, (Mon Jan 14, 6:16 pm)
Re: [PATCH] [9/31] CPA: Add simple self test at boot, Harvey Harrison, (Tue Jan 15, 6:37 am)
[PATCH] [8/31] CPA: Return the page table level in lookup_ad..., Andi Kleen, (Mon Jan 14, 6:16 pm)
[PATCH] [7/31] Extract page table dumping code from i386 fau..., Andi Kleen, (Mon Jan 14, 6:16 pm)
Re: [PATCH] [7/31] Extract page table dumping code from i386..., Harvey Harrison, (Tue Jan 15, 4:56 am)
Re: [PATCH] [7/31] Extract page table dumping code from i386..., Andi Kleen, (Tue Jan 15, 6:00 am)
Re: [PATCH] [7/31] Extract page table dumping code from i386..., Harvey Harrison, (Tue Jan 15, 6:05 am)
[PATCH] [6/31] CPA: Undo white space changes, Andi Kleen, (Mon Jan 14, 6:16 pm)
[PATCH] [5/31] Don't drop NX bit in pte modifier functions f..., Andi Kleen, (Mon Jan 14, 6:16 pm)
[PATCH] [4/31] Add pte_pgprot on i386, Andi Kleen, (Mon Jan 14, 6:16 pm)
Re: [PATCH] [4/31] Add pte_pgprot on i386, Johannes Weiner, (Tue Jan 15, 9:00 am)
[PATCH] [3/31] Add pte accessors for the global bit, Andi Kleen, (Mon Jan 14, 6:16 pm)
[PATCH] [2/31] CPA: Do a simple self test at boot, Andi Kleen, (Mon Jan 14, 6:16 pm)
Re: [PATCH] [2/31] CPA: Do a simple self test at boot, Harvey Harrison, (Tue Jan 15, 4:47 am)
Re: [PATCH] [2/31] CPA: Do a simple self test at boot, Andi Kleen, (Tue Jan 15, 5:59 am)
Re: [PATCH] [2/31] CPA: Do a simple self test at boot, Harvey Harrison, (Tue Jan 15, 6:07 am)
[PATCH] [1/31] Shrink __PAGE_KERNEL/__PAGE_KERNEL_EXEC on no..., Andi Kleen, (Mon Jan 14, 6:16 pm)