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-rw-r--r--arch/x86/mm/dump_pagetables.c4
-rw-r--r--arch/x86/mm/fault.c27
-rw-r--r--arch/x86/mm/init_32.c2
-rw-r--r--arch/x86/mm/init_64.c2
-rw-r--r--arch/x86/mm/mmap.c2
5 files changed, 28 insertions, 9 deletions
diff --git a/arch/x86/mm/dump_pagetables.c b/arch/x86/mm/dump_pagetables.c
index 167ffcac16ed..95a427e57887 100644
--- a/arch/x86/mm/dump_pagetables.c
+++ b/arch/x86/mm/dump_pagetables.c
@@ -48,7 +48,9 @@ enum address_markers_idx {
LOW_KERNEL_NR,
VMALLOC_START_NR,
VMEMMAP_START_NR,
+# ifdef CONFIG_X86_ESPFIX64
ESPFIX_START_NR,
+# endif
HIGH_KERNEL_NR,
MODULES_VADDR_NR,
MODULES_END_NR,
@@ -71,7 +73,9 @@ static struct addr_marker address_markers[] = {
{ PAGE_OFFSET, "Low Kernel Mapping" },
{ VMALLOC_START, "vmalloc() Area" },
{ VMEMMAP_START, "Vmemmap" },
+# ifdef CONFIG_X86_ESPFIX64
{ ESPFIX_BASE_ADDR, "ESPfix Area", 16 },
+# endif
{ __START_KERNEL_map, "High Kernel Mapping" },
{ MODULES_VADDR, "Modules" },
{ MODULES_END, "End Modules" },
diff --git a/arch/x86/mm/fault.c b/arch/x86/mm/fault.c
index a24194681513..9c5b32e2bdc0 100644
--- a/arch/x86/mm/fault.c
+++ b/arch/x86/mm/fault.c
@@ -3,7 +3,6 @@
* Copyright (C) 2001, 2002 Andi Kleen, SuSE Labs.
* Copyright (C) 2008-2009, Red Hat Inc., Ingo Molnar
*/
-#include <linux/magic.h> /* STACK_END_MAGIC */
#include <linux/sched.h> /* test_thread_flag(), ... */
#include <linux/kdebug.h> /* oops_begin/end, ... */
#include <linux/module.h> /* search_exception_table */
@@ -649,7 +648,6 @@ no_context(struct pt_regs *regs, unsigned long error_code,
unsigned long address, int signal, int si_code)
{
struct task_struct *tsk = current;
- unsigned long *stackend;
unsigned long flags;
int sig;
@@ -709,8 +707,7 @@ no_context(struct pt_regs *regs, unsigned long error_code,
show_fault_oops(regs, error_code, address);
- stackend = end_of_stack(tsk);
- if (tsk != &init_task && *stackend != STACK_END_MAGIC)
+ if (task_stack_end_corrupted(tsk))
printk(KERN_EMERG "Thread overran stack, or stack corrupted\n");
tsk->thread.cr2 = address;
@@ -933,8 +930,17 @@ static int spurious_fault_check(unsigned long error_code, pte_t *pte)
* cross-processor TLB flush, even if no stale TLB entries exist
* on other processors.
*
+ * Spurious faults may only occur if the TLB contains an entry with
+ * fewer permission than the page table entry. Non-present (P = 0)
+ * and reserved bit (R = 1) faults are never spurious.
+ *
* There are no security implications to leaving a stale TLB when
* increasing the permissions on a page.
+ *
+ * Returns non-zero if a spurious fault was handled, zero otherwise.
+ *
+ * See Intel Developer's Manual Vol 3 Section 4.10.4.3, bullet 3
+ * (Optional Invalidation).
*/
static noinline int
spurious_fault(unsigned long error_code, unsigned long address)
@@ -945,8 +951,17 @@ spurious_fault(unsigned long error_code, unsigned long address)
pte_t *pte;
int ret;
- /* Reserved-bit violation or user access to kernel space? */
- if (error_code & (PF_USER | PF_RSVD))
+ /*
+ * Only writes to RO or instruction fetches from NX may cause
+ * spurious faults.
+ *
+ * These could be from user or supervisor accesses but the TLB
+ * is only lazily flushed after a kernel mapping protection
+ * change, so user accesses are not expected to cause spurious
+ * faults.
+ */
+ if (error_code != (PF_WRITE | PF_PROT)
+ && error_code != (PF_INSTR | PF_PROT))
return 0;
pgd = init_mm.pgd + pgd_index(address);
diff --git a/arch/x86/mm/init_32.c b/arch/x86/mm/init_32.c
index 7d05565ba781..c8140e12816a 100644
--- a/arch/x86/mm/init_32.c
+++ b/arch/x86/mm/init_32.c
@@ -537,7 +537,7 @@ static void __init pagetable_init(void)
permanent_kmaps_init(pgd_base);
}
-pteval_t __supported_pte_mask __read_mostly = ~(_PAGE_NX | _PAGE_GLOBAL | _PAGE_IOMAP);
+pteval_t __supported_pte_mask __read_mostly = ~(_PAGE_NX | _PAGE_GLOBAL);
EXPORT_SYMBOL_GPL(__supported_pte_mask);
/* user-defined highmem size */
diff --git a/arch/x86/mm/init_64.c b/arch/x86/mm/init_64.c
index 5621c47d7a1a..5d984769cbd8 100644
--- a/arch/x86/mm/init_64.c
+++ b/arch/x86/mm/init_64.c
@@ -151,7 +151,7 @@ early_param("gbpages", parse_direct_gbpages_on);
* around without checking the pgd every time.
*/
-pteval_t __supported_pte_mask __read_mostly = ~_PAGE_IOMAP;
+pteval_t __supported_pte_mask __read_mostly = ~0;
EXPORT_SYMBOL_GPL(__supported_pte_mask);
int force_personality32;
diff --git a/arch/x86/mm/mmap.c b/arch/x86/mm/mmap.c
index 25e7e1372bb2..919b91205cd4 100644
--- a/arch/x86/mm/mmap.c
+++ b/arch/x86/mm/mmap.c
@@ -31,7 +31,7 @@
#include <linux/sched.h>
#include <asm/elf.h>
-struct __read_mostly va_alignment va_align = {
+struct va_alignment __read_mostly va_align = {
.flags = -1,
};