linux-kernel - [PATCH CPA] [28/28] Make kernel_text test match boot mapping initialization

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 for Android: free password hash cracker in your pocket

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

Date:	Thu,  3 Jan 2008 16:24:43 +0100 (CET)
From:	Andi Kleen <ak@...e.de>
To:	linux-kernel@...r.kernel.org
Subject: [PATCH CPA] [28/28] Make kernel_text test match boot mapping initialization


The boot direct mapping initialization used a different test to check if a 
page was part of the kernel mapping than c_p_a(). Fix that. Also 
round up to a large page size to be sure.

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

---
 arch/x86/mm/pageattr_32.c |    8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

Index: linux/arch/x86/mm/pageattr_32.c
===================================================================
--- linux.orig/arch/x86/mm/pageattr_32.c
+++ linux/arch/x86/mm/pageattr_32.c
@@ -183,6 +183,12 @@ static int cache_attr_changed(pte_t pte,
 	return a != (pgprot_val(prot) & _PAGE_CACHE);
 }
 
+static int text_address(unsigned long addr)
+{
+	unsigned long end = ((unsigned long)__init_end & LARGE_PAGE_MASK);
+	return addr < end + LARGE_PAGE_SIZE;
+}
+
 /*
  * Mark the address for flushing later in global_tlb_flush().
  *
@@ -237,7 +243,7 @@ __change_page_attr(struct page *page, pg
 	set_tlb_flush(address, cache_attr_changed(*kpte, prot, level),
 			level < 3);
 
-	if ((address & LARGE_PAGE_MASK) < (unsigned long)&_etext)
+	if (text_address(address))
 		ref_prot = PAGE_KERNEL_EXEC;
 
 	if (pgprot_val(prot) != pgprot_val(PAGE_KERNEL)) { 
--
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/