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Diffstat (limited to 'arch/s390/mm/mmap.c')
-rw-r--r--arch/s390/mm/mmap.c59
1 files changed, 13 insertions, 46 deletions
diff --git a/arch/s390/mm/mmap.c b/arch/s390/mm/mmap.c
index 179a2c20b01f..6e552af08c76 100644
--- a/arch/s390/mm/mmap.c
+++ b/arch/s390/mm/mmap.c
@@ -32,7 +32,7 @@
#include <asm/pgalloc.h>
unsigned long mmap_rnd_mask;
-unsigned long mmap_align_mask;
+static unsigned long mmap_align_mask;
static unsigned long stack_maxrandom_size(void)
{
@@ -60,22 +60,20 @@ static inline int mmap_is_legacy(void)
return sysctl_legacy_va_layout;
}
-static unsigned long mmap_rnd(void)
+unsigned long arch_mmap_rnd(void)
{
- if (!(current->flags & PF_RANDOMIZE))
- return 0;
if (is_32bit_task())
return (get_random_int() & 0x7ff) << PAGE_SHIFT;
else
return (get_random_int() & mmap_rnd_mask) << PAGE_SHIFT;
}
-static unsigned long mmap_base_legacy(void)
+static unsigned long mmap_base_legacy(unsigned long rnd)
{
- return TASK_UNMAPPED_BASE + mmap_rnd();
+ return TASK_UNMAPPED_BASE + rnd;
}
-static inline unsigned long mmap_base(void)
+static inline unsigned long mmap_base(unsigned long rnd)
{
unsigned long gap = rlimit(RLIMIT_STACK);
@@ -84,7 +82,7 @@ static inline unsigned long mmap_base(void)
else if (gap > MAX_GAP)
gap = MAX_GAP;
gap &= PAGE_MASK;
- return STACK_TOP - stack_maxrandom_size() - mmap_rnd() - gap;
+ return STACK_TOP - stack_maxrandom_size() - rnd - gap;
}
unsigned long
@@ -179,40 +177,6 @@ arch_get_unmapped_area_topdown(struct file *filp, const unsigned long addr0,
return addr;
}
-unsigned long randomize_et_dyn(void)
-{
- unsigned long base;
-
- base = STACK_TOP / 3 * 2;
- if (!is_32bit_task())
- /* Align to 4GB */
- base &= ~((1UL << 32) - 1);
- return base + mmap_rnd();
-}
-
-#ifndef CONFIG_64BIT
-
-/*
- * This function, called very early during the creation of a new
- * process VM image, sets up which VM layout function to use:
- */
-void arch_pick_mmap_layout(struct mm_struct *mm)
-{
- /*
- * Fall back to the standard layout if the personality
- * bit is set, or if the expected stack growth is unlimited:
- */
- if (mmap_is_legacy()) {
- mm->mmap_base = mmap_base_legacy();
- mm->get_unmapped_area = arch_get_unmapped_area;
- } else {
- mm->mmap_base = mmap_base();
- mm->get_unmapped_area = arch_get_unmapped_area_topdown;
- }
-}
-
-#else
-
int s390_mmap_check(unsigned long addr, unsigned long len, unsigned long flags)
{
if (is_compat_task() || (TASK_SIZE >= (1UL << 53)))
@@ -273,15 +237,20 @@ s390_get_unmapped_area_topdown(struct file *filp, const unsigned long addr,
*/
void arch_pick_mmap_layout(struct mm_struct *mm)
{
+ unsigned long random_factor = 0UL;
+
+ if (current->flags & PF_RANDOMIZE)
+ random_factor = arch_mmap_rnd();
+
/*
* Fall back to the standard layout if the personality
* bit is set, or if the expected stack growth is unlimited:
*/
if (mmap_is_legacy()) {
- mm->mmap_base = mmap_base_legacy();
+ mm->mmap_base = mmap_base_legacy(random_factor);
mm->get_unmapped_area = s390_get_unmapped_area;
} else {
- mm->mmap_base = mmap_base();
+ mm->mmap_base = mmap_base(random_factor);
mm->get_unmapped_area = s390_get_unmapped_area_topdown;
}
}
@@ -317,5 +286,3 @@ static int __init setup_mmap_rnd(void)
return 0;
}
early_initcall(setup_mmap_rnd);
-
-#endif