diff --git a/arch/x86_64/ia32/ia32_binfmt.c b/arch/x86_64/ia32/ia32_binfmt.c
index 93d568dfa762168c2baf2b391e7fe255beff77e1..99b522052d16d9cae2f3c07f11afd9c3cdfb59e9 100644
--- a/arch/x86_64/ia32/ia32_binfmt.c
+++ b/arch/x86_64/ia32/ia32_binfmt.c
@@ -312,6 +312,10 @@ MODULE_AUTHOR("Eric Youngdale, Andi Kleen");
static void elf32_init(struct pt_regs *);
+#define ARCH_HAS_SETUP_ADDITIONAL_PAGES 1
+#define arch_setup_additional_pages syscall32_setup_pages
+extern int syscall32_setup_pages(struct linux_binprm *, int exstack);
+
#include "../../../fs/binfmt_elf.c"
static void elf32_init(struct pt_regs *regs)
diff --git a/arch/x86_64/ia32/syscall32.c b/arch/x86_64/ia32/syscall32.c
index 399ff498509978c834420c82bc539ed4bfe6b268..01d8db1a1c09c7bff982a740bf5222735e996893 100644
--- a/arch/x86_64/ia32/syscall32.c
+++ b/arch/x86_64/ia32/syscall32.c
@@ -9,6 +9,7 @@
#include <linux/gfp.h>
#include <linux/init.h>
#include <linux/stringify.h>
+#include <linux/security.h>
#include <asm/proto.h>
#include <asm/tlbflush.h>
#include <asm/ia32_unistd.h>
@@ -30,51 +31,57 @@ extern int sysctl_vsyscall32;
char *syscall32_page;
static int use_sysenter = -1;
-/*
- * Map the 32bit vsyscall page on demand.
- *
- * RED-PEN: This knows too much about high level VM.
- *
- * Alternative would be to generate a vma with appropriate backing options
- * and let it be handled by generic VM.
- */
-int __map_syscall32(struct mm_struct *mm, unsigned long address)
-{
- pgd_t *pgd;
- pud_t *pud;
- pte_t *pte;
- pmd_t *pmd;
- int err = -ENOMEM;
-
- spin_lock(&mm->page_table_lock);
- pgd = pgd_offset(mm, address);
- pud = pud_alloc(mm, pgd, address);
- if (pud) {
- pmd = pmd_alloc(mm, pud, address);
- if (pmd && (pte = pte_alloc_map(mm, pmd, address)) != NULL) {
- if (pte_none(*pte)) {
- set_pte(pte,
- mk_pte(virt_to_page(syscall32_page),
- PAGE_KERNEL_VSYSCALL32));
- }
- /* Flush only the local CPU. Other CPUs taking a fault
- will just end up here again
- This probably not needed and just paranoia. */
- __flush_tlb_one(address);
- err = 0;
- }
- }
- spin_unlock(&mm->page_table_lock);
- return err;
+static struct page *
+syscall32_nopage(struct vm_area_struct *vma, unsigned long adr, int *type)
+{
+ struct page *p = virt_to_page(adr - vma->vm_start + syscall32_page);
+ get_page(p);
+ return p;
}
-int map_syscall32(struct mm_struct *mm, unsigned long address)
+/* Prevent VMA merging */
+static void syscall32_vma_close(struct vm_area_struct *vma)
{
- int err;
- down_read(&mm->mmap_sem);
- err = __map_syscall32(mm, address);
- up_read(&mm->mmap_sem);
- return err;
+}
+
+static struct vm_operations_struct syscall32_vm_ops = {
+ .close = syscall32_vma_close,
+ .nopage = syscall32_nopage,
+};
+
+struct linux_binprm;
+
+/* Setup a VMA at program startup for the vsyscall page */
+int syscall32_setup_pages(struct linux_binprm *bprm, int exstack)
+{
+ int npages = (VSYSCALL32_END - VSYSCALL32_BASE) >> PAGE_SHIFT;
+ struct vm_area_struct *vma;
+ struct mm_struct *mm = current->mm;
+
+ vma = kmem_cache_alloc(vm_area_cachep, SLAB_KERNEL);
+ if (!vma)
+ return -ENOMEM;
+ if (security_vm_enough_memory(npages)) {
+ kmem_cache_free(vm_area_cachep, vma);
+ return -ENOMEM;
+ }
+
+ memset(vma, 0, sizeof(struct vm_area_struct));
+ /* Could randomize here */
+ vma->vm_start = VSYSCALL32_BASE;
+ vma->vm_end = VSYSCALL32_END;
+ /* MAYWRITE to allow gdb to COW and set breakpoints */
+ vma->vm_flags = VM_READ|VM_EXEC|VM_MAYREAD|VM_MAYEXEC|VM_MAYEXEC|VM_MAYWRITE;
+ vma->vm_flags |= mm->def_flags;
+ vma->vm_page_prot = protection_map[vma->vm_flags & 7];
+ vma->vm_ops = &syscall32_vm_ops;
+ vma->vm_mm = mm;
+
+ down_write(&mm->mmap_sem);
+ insert_vm_struct(mm, vma);
+ mm->total_vm += npages;
+ up_write(&mm->mmap_sem);
+ return 0;
}
static int __init init_syscall32(void)
@@ -82,7 +89,6 @@ static int __init init_syscall32(void)
syscall32_page = (void *)get_zeroed_page(GFP_KERNEL);
if (!syscall32_page)
panic("Cannot allocate syscall32 page");
- SetPageReserved(virt_to_page(syscall32_page));
if (use_sysenter > 0) {
memcpy(syscall32_page, syscall32_sysenter,
syscall32_sysenter_end - syscall32_sysenter);
diff --git a/arch/x86_64/mm/fault.c b/arch/x86_64/mm/fault.c
index 5724370475cc10816730aeb7375e4193206f36fc..d4676ca091449bd87c075956057716f57decd406 100644
--- a/arch/x86_64/mm/fault.c
+++ b/arch/x86_64/mm/fault.c
@@ -458,17 +458,6 @@ asmlinkage void do_page_fault(struct pt_regs *regs, unsigned long error_code)
up_read(&mm->mmap_sem);
bad_area_nosemaphore:
-
-#ifdef CONFIG_IA32_EMULATION
- /* 32bit vsyscall. map on demand. */
- if (test_thread_flag(TIF_IA32) &&
- address >= VSYSCALL32_BASE && address < VSYSCALL32_END) {
- if (map_syscall32(mm, address) < 0)
- goto out_of_memory2;
- return;
- }
-#endif
-
/* User mode accesses just cause a SIGSEGV */
if (error_code & 4) {
if (is_prefetch(regs, address, error_code))
@@ -550,7 +539,6 @@ asmlinkage void do_page_fault(struct pt_regs *regs, unsigned long error_code)
*/
out_of_memory:
up_read(&mm->mmap_sem);
-out_of_memory2:
if (current->pid == 1) {
yield();
goto again;
diff --git a/arch/x86_64/mm/init.c b/arch/x86_64/mm/init.c
index b0d604551d862ad474d6e49670cbc11a371a7f96..dbe53b4c7e66c0c0f75fbccfb8d404961d7eb10d 100644
--- a/arch/x86_64/mm/init.c
+++ b/arch/x86_64/mm/init.c
@@ -583,9 +583,9 @@ static __init int x8664_sysctl_init(void)
__initcall(x8664_sysctl_init);
#endif
-/* Pseudo VMAs to allow ptrace access for the vsyscall pages. x86-64 has two
- different ones: one for 32bit and one for 64bit. Use the appropiate
- for the target task. */
+/* A pseudo VMAs to allow ptrace access for the vsyscall page. This only
+ covers the 64bit vsyscall page now. 32bit has a real VMA now and does
+ not need special handling anymore. */
static struct vm_area_struct gate_vma = {
.vm_start = VSYSCALL_START,
@@ -593,22 +593,11 @@ static struct vm_area_struct gate_vma = {
.vm_page_prot = PAGE_READONLY
};
-static struct vm_area_struct gate32_vma = {
- .vm_start = VSYSCALL32_BASE,
- .vm_end = VSYSCALL32_END,
- .vm_page_prot = PAGE_READONLY
-};
-
struct vm_area_struct *get_gate_vma(struct task_struct *tsk)
{
#ifdef CONFIG_IA32_EMULATION
- if (test_tsk_thread_flag(tsk, TIF_IA32)) {
- /* lookup code assumes the pages are present. set them up
- now */
- if (__map_syscall32(tsk->mm, VSYSCALL32_BASE) < 0)
- return NULL;
- return &gate32_vma;
- }
+ if (test_tsk_thread_flag(tsk, TIF_IA32))
+ return NULL;
#endif
return &gate_vma;
}
@@ -616,6 +605,8 @@ struct vm_area_struct *get_gate_vma(struct task_struct *tsk)
int in_gate_area(struct task_struct *task, unsigned long addr)
{
struct vm_area_struct *vma = get_gate_vma(task);
+ if (!vma)
+ return 0;
return (addr >= vma->vm_start) && (addr < vma->vm_end);
}
@@ -625,6 +616,5 @@ int in_gate_area(struct task_struct *task, unsigned long addr)
*/
int in_gate_area_no_task(unsigned long addr)
{
- return (((addr >= VSYSCALL_START) && (addr < VSYSCALL_END)) ||
- ((addr >= VSYSCALL32_BASE) && (addr < VSYSCALL32_END)));
+ return (addr >= VSYSCALL_START) && (addr < VSYSCALL_END);
}
diff --git a/include/asm-x86_64/proto.h b/include/asm-x86_64/proto.h
index c59526ee54da668b388597892c03c914abe13968..217bd9ace69b7b56a83ca0f556f043df29c6b7f1 100644
--- a/include/asm-x86_64/proto.h
+++ b/include/asm-x86_64/proto.h
@@ -69,8 +69,6 @@ extern void __die(const char * str, struct pt_regs * regs, long err);
extern void __show_regs(struct pt_regs * regs);
extern void show_regs(struct pt_regs * regs);
-extern int map_syscall32(struct mm_struct *mm, unsigned long address);
-extern int __map_syscall32(struct mm_struct *mm, unsigned long address);
extern char *syscall32_page;
extern void syscall32_cpu_init(void);