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>] [day] [month] [year] [list]
Message-Id: <455B3868.76E4.0078.0@novell.com>
Date:	Wed, 15 Nov 2006 14:55:20 +0000
From:	"Jan Beulich" <jbeulich@...ell.com>
To:	<linux-kernel@...r.kernel.org>
Subject: [PATCH] i386: clear_fixmap() should not use set_pte()

While not strictly required with the current code (as the upper half of
page table entries generated by __set_fixmap() cannot be non-zero due
to the second parameter of this function being 'unsigned long'), the
use of set_pte() in __set_fixmap() in the context of clear_fixmap() is
still improper with CONFIG_X86_PAE (see the respective comment in
include/asm-i386/pgtable-3level.h) and would turn into a bug if that
second parameter ever gets changed to a 64-bit type.

Signed-off-by: Jan Beulich <jbeulich@...ell.com>

--- linux-2.6.19-rc5/arch/i386/mm/pgtable.c	2006-11-08 09:21:37.000000000 +0100
+++ 2.6.19-rc5-i386-clear_fixmap/arch/i386/mm/pgtable.c	2006-11-06 12:13:29.000000000 +0100
@@ -95,8 +95,11 @@ static void set_pte_pfn(unsigned long va
 		return;
 	}
 	pte = pte_offset_kernel(pmd, vaddr);
-	/* <pfn,flags> stored as-is, to permit clearing entries */
-	set_pte(pte, pfn_pte(pfn, flags));
+	if (pgprot_val(flags))
+		/* <pfn,flags> stored as-is, to permit clearing entries */
+		set_pte(pte, pfn_pte(pfn, flags));
+	else
+		pte_clear(&init_mm, vaddr, pte);
 
 	/*
 	 * It's enough to flush this one mapping.


-
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/

Powered by blists - more mailing lists

Powered by Openwall GNU/*/Linux Powered by OpenVZ