Commit-ID: c7d2361f7524f365c1ae42f47880e3fa9efb2c2a
Gitweb: http://git.kernel.org/tip/c7d2361f7524f365c1ae42f47880e3fa9efb2c2a
Author: Thomas Garnier <thgar...@google.com>
AuthorDate: Tue, 9 Aug 2016 10:11:04 -0700
Committer: Ingo Molnar <mi...@kernel.org>
CommitDate: Wed, 10 Aug 2016 14:45:19 +0200
x86/mm/KASLR: Fix physical memory calculation on KASLR memory randomization
Initialize KASLR memory randomization after max_pfn is initialized. Also
ensure the size is rounded up. It could create problems on machines
with more than 1Tb of memory on certain random addresses.
Signed-off-by: Thomas Garnier <thgar...@google.com>
Cc: Aleksey Makarov <aleksey.maka...@linaro.org>
Cc: Andrew Morton <a...@linux-foundation.org>
Cc: Andy Lutomirski <l...@kernel.org>
Cc: Baoquan He <b...@redhat.com>
Cc: Borislav Petkov <b...@alien8.de>
Cc: Borislav Petkov <b...@suse.de>
Cc: Brian Gerst <brge...@gmail.com>
Cc: Christian Borntraeger <borntrae...@de.ibm.com>
Cc: Dan Williams <dan.j.willi...@intel.com>
Cc: Dave Hansen <dave.han...@linux.intel.com>
Cc: Dave Young <dyo...@redhat.com>
Cc: Denys Vlasenko <dvlas...@redhat.com>
Cc: Fabian Frederick <f...@skynet.be>
Cc: H. Peter Anvin <h...@zytor.com>
Cc: Joerg Roedel <jroe...@suse.de>
Cc: Josh Poimboeuf <jpoim...@redhat.com>
Cc: Kees Cook <keesc...@chromium.org>
Cc: Linus Torvalds <torva...@linux-foundation.org>
Cc: Lv Zheng <lv.zh...@intel.com>
Cc: Mark Salter <msal...@redhat.com>
Cc: Peter Zijlstra <pet...@infradead.org>
Cc: Rafael J . Wysocki <rafael.j.wyso...@intel.com>
Cc: Thomas Gleixner <t...@linutronix.de>
Cc: Toshi Kani <toshi.k...@hp.com>
Cc: kernel-harden...@lists.openwall.com
Fixes: 021182e52fe0 ("Enable KASLR for physical mapping memory regions")
Link:
http://lkml.kernel.org/r/1470762665-88032-1-git-send-email-thgar...@google.com
Signed-off-by: Ingo Molnar <mi...@kernel.org>
---
arch/x86/kernel/setup.c | 8 ++++++--
arch/x86/mm/kaslr.c | 2 +-
2 files changed, 7 insertions(+), 3 deletions(-)
diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c
index 991b779..95cf31c 100644
--- a/arch/x86/kernel/setup.c
+++ b/arch/x86/kernel/setup.c
@@ -936,8 +936,6 @@ void __init setup_arch(char **cmdline_p)
x86_init.oem.arch_setup();
- kernel_randomize_memory();
-
iomem_resource.end = (1ULL << boot_cpu_data.x86_phys_bits) - 1;
setup_memory_map();
parse_setup_data();
@@ -1055,6 +1053,12 @@ void __init setup_arch(char **cmdline_p)
max_possible_pfn = max_pfn;
+ /*
+ * Define random base addresses for memory sections after max_pfn is
+ * defined and before each memory section base is used.
+ */
+ kernel_randomize_memory();
+
#ifdef CONFIG_X86_32
/* max_low_pfn get updated here */
find_low_pfn_range();
diff --git a/arch/x86/mm/kaslr.c b/arch/x86/mm/kaslr.c
index 26dccd6..ec8654f 100644
--- a/arch/x86/mm/kaslr.c
+++ b/arch/x86/mm/kaslr.c
@@ -97,7 +97,7 @@ void __init kernel_randomize_memory(void)
* add padding if needed (especially for memory hotplug support).
*/
BUG_ON(kaslr_regions[0].base != &page_offset_base);
- memory_tb = ((max_pfn << PAGE_SHIFT) >> TB_SHIFT) +
+ memory_tb = DIV_ROUND_UP(max_pfn << PAGE_SHIFT, 1UL << TB_SHIFT) +
CONFIG_RANDOMIZE_MEMORY_PHYSICAL_PADDING;
/* Adapt phyiscal memory region size based on available memory */
