Loading...
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 | /*
* IA-32 ELF support.
*
* Copyright (C) 1999 Arun Sharma <arun.sharma@intel.com>
* Copyright (C) 2001 Hewlett-Packard Co
* David Mosberger-Tang <davidm@hpl.hp.com>
*
* 06/16/00 A. Mallick initialize csd/ssd/tssd/cflg for ia32_load_state
* 04/13/01 D. Mosberger dropped saving tssd in ar.k1---it's not needed
* 09/14/01 D. Mosberger fixed memory management for gdt/tss page
*/
#include <linux/types.h>
#include <linux/mm.h>
#include <linux/security.h>
#include <asm/param.h>
#include <asm/signal.h>
#include "ia32priv.h"
#include "elfcore32.h"
/* Override some function names */
#undef start_thread
#define start_thread ia32_start_thread
#define elf_format elf32_format
#define init_elf_binfmt init_elf32_binfmt
#define exit_elf_binfmt exit_elf32_binfmt
#undef CLOCKS_PER_SEC
#define CLOCKS_PER_SEC IA32_CLOCKS_PER_SEC
extern void ia64_elf32_init (struct pt_regs *regs);
static void elf32_set_personality (void);
static unsigned long __attribute ((unused))
randomize_stack_top(unsigned long stack_top);
#define setup_arg_pages(bprm,tos,exec) ia32_setup_arg_pages(bprm,exec)
#define elf_map elf32_map
#undef SET_PERSONALITY
#define SET_PERSONALITY(ex) elf32_set_personality()
#define elf_read_implies_exec(ex, have_pt_gnu_stack) (!(have_pt_gnu_stack))
/* Ugly but avoids duplication */
#include "../../../fs/binfmt_elf.c"
extern struct page *ia32_shared_page[];
extern unsigned long *ia32_gdt;
extern struct page *ia32_gate_page;
int
ia32_install_shared_page (struct vm_area_struct *vma, struct vm_fault *vmf)
{
vmf->page = ia32_shared_page[smp_processor_id()];
get_page(vmf->page);
return 0;
}
int
ia32_install_gate_page (struct vm_area_struct *vma, struct vm_fault *vmf)
{
vmf->page = ia32_gate_page;
get_page(vmf->page);
return 0;
}
static struct vm_operations_struct ia32_shared_page_vm_ops = {
.fault = ia32_install_shared_page
};
static struct vm_operations_struct ia32_gate_page_vm_ops = {
.fault = ia32_install_gate_page
};
void
ia64_elf32_init (struct pt_regs *regs)
{
struct vm_area_struct *vma;
/*
* Map GDT below 4GB, where the processor can find it. We need to map
* it with privilege level 3 because the IVE uses non-privileged accesses to these
* tables. IA-32 segmentation is used to protect against IA-32 accesses to them.
*/
vma = kmem_cache_zalloc(vm_area_cachep, GFP_KERNEL);
if (vma) {
vma->vm_mm = current->mm;
vma->vm_start = IA32_GDT_OFFSET;
vma->vm_end = vma->vm_start + PAGE_SIZE;
vma->vm_page_prot = PAGE_SHARED;
vma->vm_flags = VM_READ|VM_MAYREAD|VM_RESERVED;
vma->vm_ops = &ia32_shared_page_vm_ops;
down_write(¤t->mm->mmap_sem);
{
if (insert_vm_struct(current->mm, vma)) {
kmem_cache_free(vm_area_cachep, vma);
up_write(¤t->mm->mmap_sem);
BUG();
}
}
up_write(¤t->mm->mmap_sem);
}
/*
* When user stack is not executable, push sigreturn code to stack makes
* segmentation fault raised when returning to kernel. So now sigreturn
* code is locked in specific gate page, which is pointed by pretcode
* when setup_frame_ia32
*/
vma = kmem_cache_zalloc(vm_area_cachep, GFP_KERNEL);
if (vma) {
vma->vm_mm = current->mm;
vma->vm_start = IA32_GATE_OFFSET;
vma->vm_end = vma->vm_start + PAGE_SIZE;
vma->vm_page_prot = PAGE_COPY_EXEC;
vma->vm_flags = VM_READ | VM_MAYREAD | VM_EXEC
| VM_MAYEXEC | VM_RESERVED;
vma->vm_ops = &ia32_gate_page_vm_ops;
down_write(¤t->mm->mmap_sem);
{
if (insert_vm_struct(current->mm, vma)) {
kmem_cache_free(vm_area_cachep, vma);
up_write(¤t->mm->mmap_sem);
BUG();
}
}
up_write(¤t->mm->mmap_sem);
}
/*
* Install LDT as anonymous memory. This gives us all-zero segment descriptors
* until a task modifies them via modify_ldt().
*/
vma = kmem_cache_zalloc(vm_area_cachep, GFP_KERNEL);
if (vma) {
vma->vm_mm = current->mm;
vma->vm_start = IA32_LDT_OFFSET;
vma->vm_end = vma->vm_start + PAGE_ALIGN(IA32_LDT_ENTRIES*IA32_LDT_ENTRY_SIZE);
vma->vm_page_prot = PAGE_SHARED;
vma->vm_flags = VM_READ|VM_WRITE|VM_MAYREAD|VM_MAYWRITE;
down_write(¤t->mm->mmap_sem);
{
if (insert_vm_struct(current->mm, vma)) {
kmem_cache_free(vm_area_cachep, vma);
up_write(¤t->mm->mmap_sem);
BUG();
}
}
up_write(¤t->mm->mmap_sem);
}
ia64_psr(regs)->ac = 0; /* turn off alignment checking */
regs->loadrs = 0;
/*
* According to the ABI %edx points to an `atexit' handler. Since we don't have
* one we'll set it to 0 and initialize all the other registers just to make
* things more deterministic, ala the i386 implementation.
*/
regs->r8 = 0; /* %eax */
regs->r11 = 0; /* %ebx */
regs->r9 = 0; /* %ecx */
regs->r10 = 0; /* %edx */
regs->r13 = 0; /* %ebp */
regs->r14 = 0; /* %esi */
regs->r15 = 0; /* %edi */
current->thread.eflag = IA32_EFLAG;
current->thread.fsr = IA32_FSR_DEFAULT;
current->thread.fcr = IA32_FCR_DEFAULT;
current->thread.fir = 0;
current->thread.fdr = 0;
/*
* Setup GDTD. Note: GDTD is the descrambled version of the pseudo-descriptor
* format defined by Figure 3-11 "Pseudo-Descriptor Format" in the IA-32
* architecture manual. Also note that the only fields that are not ignored are
* `base', `limit', 'G', `P' (must be 1) and `S' (must be 0).
*/
regs->r31 = IA32_SEG_UNSCRAMBLE(IA32_SEG_DESCRIPTOR(IA32_GDT_OFFSET, IA32_PAGE_SIZE - 1,
0, 0, 0, 1, 0, 0, 0));
/* Setup the segment selectors */
regs->r16 = (__USER_DS << 16) | __USER_DS; /* ES == DS, GS, FS are zero */
regs->r17 = (__USER_DS << 16) | __USER_CS; /* SS, CS; ia32_load_state() sets TSS and LDT */
ia32_load_segment_descriptors(current);
ia32_load_state(current);
}
/*
* Undo the override of setup_arg_pages() without this ia32_setup_arg_pages()
* will suffer infinite self recursion.
*/
#undef setup_arg_pages
int
ia32_setup_arg_pages (struct linux_binprm *bprm, int executable_stack)
{
int ret;
ret = setup_arg_pages(bprm, IA32_STACK_TOP, executable_stack);
if (!ret) {
/*
* Can't do it in ia64_elf32_init(). Needs to be done before
* calls to elf32_map()
*/
current->thread.ppl = ia32_init_pp_list();
}
return ret;
}
static void
elf32_set_personality (void)
{
set_personality(PER_LINUX32);
current->thread.map_base = IA32_PAGE_OFFSET/3;
}
static unsigned long
elf32_map(struct file *filep, unsigned long addr, struct elf_phdr *eppnt,
int prot, int type, unsigned long unused)
{
unsigned long pgoff = (eppnt->p_vaddr) & ~IA32_PAGE_MASK;
return ia32_do_mmap(filep, (addr & IA32_PAGE_MASK), eppnt->p_filesz + pgoff, prot, type,
eppnt->p_offset - pgoff);
}
#define cpu_uses_ia32el() (local_cpu_data->family > 0x1f)
static int __init check_elf32_binfmt(void)
{
if (cpu_uses_ia32el()) {
printk("Please use IA-32 EL for executing IA-32 binaries\n");
unregister_binfmt(&elf_format);
}
return 0;
}
module_init(check_elf32_binfmt)
|