diff options
| -rw-r--r-- | arch/s390/include/asm/elf.h | 8 | ||||
| -rw-r--r-- | arch/s390/include/asm/pgtable.h | 4 | ||||
| -rw-r--r-- | arch/s390/kernel/process.c | 10 | ||||
| -rw-r--r-- | arch/s390/mm/init.c | 9 | ||||
| -rw-r--r-- | arch/s390/mm/mmap.c | 142 |
5 files changed, 155 insertions, 18 deletions
diff --git a/arch/s390/include/asm/elf.h b/arch/s390/include/asm/elf.h index f6e43d3..c9df40b 100644 --- a/arch/s390/include/asm/elf.h +++ b/arch/s390/include/asm/elf.h @@ -163,8 +163,8 @@ extern unsigned int vdso_enabled; the loader. We need to make sure that it is out of the way of the program that it will "exec", and that there is sufficient room for the brk. */ -extern unsigned long randomize_et_dyn(unsigned long base); -#define ELF_ET_DYN_BASE (randomize_et_dyn(STACK_TOP / 3 * 2)) +extern unsigned long randomize_et_dyn(void); +#define ELF_ET_DYN_BASE randomize_et_dyn() /* This yields a mask that user programs can use to figure out what instruction set this CPU supports. */ @@ -209,7 +209,9 @@ do { \ } while (0) #endif /* CONFIG_COMPAT */ -#define STACK_RND_MASK 0x7ffUL +extern unsigned long mmap_rnd_mask; + +#define STACK_RND_MASK (mmap_rnd_mask) #define ARCH_DLINFO \ do { \ diff --git a/arch/s390/include/asm/pgtable.h b/arch/s390/include/asm/pgtable.h index 5e102422..b8641b4 100644 --- a/arch/s390/include/asm/pgtable.h +++ b/arch/s390/include/asm/pgtable.h @@ -1779,6 +1779,10 @@ extern int s390_enable_sie(void); extern int s390_enable_skey(void); extern void s390_reset_cmma(struct mm_struct *mm); +/* s390 has a private copy of get unmapped area to deal with cache synonyms */ +#define HAVE_ARCH_UNMAPPED_AREA +#define HAVE_ARCH_UNMAPPED_AREA_TOPDOWN + /* * No page table caches to initialise */ diff --git a/arch/s390/kernel/process.c b/arch/s390/kernel/process.c index aa7a839..2c1eb4f 100644 --- a/arch/s390/kernel/process.c +++ b/arch/s390/kernel/process.c @@ -243,13 +243,3 @@ unsigned long arch_randomize_brk(struct mm_struct *mm) ret = PAGE_ALIGN(mm->brk + brk_rnd()); return (ret > mm->brk) ? ret : mm->brk; } - -unsigned long randomize_et_dyn(unsigned long base) -{ - unsigned long ret; - - if (!(current->flags & PF_RANDOMIZE)) - return base; - ret = PAGE_ALIGN(base + brk_rnd()); - return (ret > base) ? ret : base; -} diff --git a/arch/s390/mm/init.c b/arch/s390/mm/init.c index c7235e0..d35b151 100644 --- a/arch/s390/mm/init.c +++ b/arch/s390/mm/init.c @@ -71,13 +71,16 @@ static void __init setup_zero_pages(void) break; case 0x2827: /* zEC12 */ case 0x2828: /* zEC12 */ - default: order = 5; break; + case 0x2964: /* z13 */ + default: + order = 7; + break; } /* Limit number of empty zero pages for small memory sizes */ - if (order > 2 && totalram_pages <= 16384) - order = 2; + while (order > 2 && (totalram_pages >> 10) < (1UL << order)) + order--; empty_zero_page = __get_free_pages(GFP_KERNEL | __GFP_ZERO, order); if (!empty_zero_page) diff --git a/arch/s390/mm/mmap.c b/arch/s390/mm/mmap.c index 9b436c2..d008f638 100644 --- a/arch/s390/mm/mmap.c +++ b/arch/s390/mm/mmap.c @@ -28,8 +28,12 @@ #include <linux/module.h> #include <linux/random.h> #include <linux/compat.h> +#include <linux/security.h> #include <asm/pgalloc.h> +unsigned long mmap_rnd_mask; +unsigned long mmap_align_mask; + static unsigned long stack_maxrandom_size(void) { if (!(current->flags & PF_RANDOMIZE)) @@ -60,8 +64,10 @@ static unsigned long mmap_rnd(void) { if (!(current->flags & PF_RANDOMIZE)) return 0; - /* 8MB randomization for mmap_base */ - return (get_random_int() & 0x7ffUL) << PAGE_SHIFT; + 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) @@ -81,6 +87,106 @@ static inline unsigned long mmap_base(void) return STACK_TOP - stack_maxrandom_size() - mmap_rnd() - gap; } +unsigned long +arch_get_unmapped_area(struct file *filp, unsigned long addr, + unsigned long len, unsigned long pgoff, unsigned long flags) +{ + struct mm_struct *mm = current->mm; + struct vm_area_struct *vma; + struct vm_unmapped_area_info info; + int do_color_align; + + if (len > TASK_SIZE - mmap_min_addr) + return -ENOMEM; + + if (flags & MAP_FIXED) + return addr; + + if (addr) { + addr = PAGE_ALIGN(addr); + vma = find_vma(mm, addr); + if (TASK_SIZE - len >= addr && addr >= mmap_min_addr && + (!vma || addr + len <= vma->vm_start)) + return addr; + } + + do_color_align = 0; + if (filp || (flags & MAP_SHARED)) + do_color_align = !is_32bit_task(); + + info.flags = 0; + info.length = len; + info.low_limit = mm->mmap_base; + info.high_limit = TASK_SIZE; + info.align_mask = do_color_align ? (mmap_align_mask << PAGE_SHIFT) : 0; + info.align_offset = pgoff << PAGE_SHIFT; + return vm_unmapped_area(&info); +} + +unsigned long +arch_get_unmapped_area_topdown(struct file *filp, const unsigned long addr0, + const unsigned long len, const unsigned long pgoff, + const unsigned long flags) +{ + struct vm_area_struct *vma; + struct mm_struct *mm = current->mm; + unsigned long addr = addr0; + struct vm_unmapped_area_info info; + int do_color_align; + + /* requested length too big for entire address space */ + if (len > TASK_SIZE - mmap_min_addr) + return -ENOMEM; + + if (flags & MAP_FIXED) + return addr; + + /* requesting a specific address */ + if (addr) { + addr = PAGE_ALIGN(addr); + vma = find_vma(mm, addr); + if (TASK_SIZE - len >= addr && addr >= mmap_min_addr && + (!vma || addr + len <= vma->vm_start)) + return addr; + } + + do_color_align = 0; + if (filp || (flags & MAP_SHARED)) + do_color_align = !is_32bit_task(); + + info.flags = VM_UNMAPPED_AREA_TOPDOWN; + info.length = len; + info.low_limit = max(PAGE_SIZE, mmap_min_addr); + info.high_limit = mm->mmap_base; + info.align_mask = do_color_align ? (mmap_align_mask << PAGE_SHIFT) : 0; + info.align_offset = pgoff << PAGE_SHIFT; + addr = vm_unmapped_area(&info); + + /* + * A failed mmap() very likely causes application failure, + * so fall back to the bottom-up function here. This scenario + * can happen with large stack limits and large mmap() + * allocations. + */ + if (addr & ~PAGE_MASK) { + VM_BUG_ON(addr != -ENOMEM); + info.flags = 0; + info.low_limit = TASK_UNMAPPED_BASE; + info.high_limit = TASK_SIZE; + addr = vm_unmapped_area(&info); + } + + return addr; +} + +unsigned long randomize_et_dyn(void) +{ + unsigned long base; + + base = (STACK_TOP / 3 * 2) & (~mmap_align_mask << PAGE_SHIFT); + return base + mmap_rnd(); +} + #ifndef CONFIG_64BIT /* @@ -177,4 +283,36 @@ void arch_pick_mmap_layout(struct mm_struct *mm) } } +static int __init setup_mmap_rnd(void) +{ + struct cpuid cpu_id; + + get_cpu_id(&cpu_id); + switch (cpu_id.machine) { + case 0x9672: + case 0x2064: + case 0x2066: + case 0x2084: + case 0x2086: + case 0x2094: + case 0x2096: + case 0x2097: + case 0x2098: + case 0x2817: + case 0x2818: + case 0x2827: + case 0x2828: + mmap_rnd_mask = 0x7ffUL; + mmap_align_mask = 0UL; + break; + case 0x2964: /* z13 */ + default: + mmap_rnd_mask = 0x3ff80UL; + mmap_align_mask = 0x7fUL; + break; + } + return 0; +} +early_initcall(setup_mmap_rnd); + #endif |
