diff options
Diffstat (limited to 'arch/arm/kernel/process.c')
| -rw-r--r-- | arch/arm/kernel/process.c | 38 |
1 files changed, 28 insertions, 10 deletions
diff --git a/arch/arm/kernel/process.c b/arch/arm/kernel/process.c index 971d65c253a..e11b523db33 100644 --- a/arch/arm/kernel/process.c +++ b/arch/arm/kernel/process.c @@ -526,22 +526,40 @@ unsigned long arch_randomize_brk(struct mm_struct *mm) #ifdef CONFIG_MMU /* * The vectors page is always readable from user space for the - * atomic helpers and the signal restart code. Let's declare a mapping - * for it so it is visible through ptrace and /proc/<pid>/mem. + * atomic helpers and the signal restart code. Insert it into the + * gate_vma so that it is visible through ptrace and /proc/<pid>/mem. */ +static struct vm_area_struct gate_vma; -int vectors_user_mapping(void) +static int __init gate_vma_init(void) { - struct mm_struct *mm = current->mm; - return install_special_mapping(mm, 0xffff0000, PAGE_SIZE, - VM_READ | VM_EXEC | - VM_MAYREAD | VM_MAYEXEC | - VM_ALWAYSDUMP | VM_RESERVED, - NULL); + gate_vma.vm_start = 0xffff0000; + gate_vma.vm_end = 0xffff0000 + PAGE_SIZE; + gate_vma.vm_page_prot = PAGE_READONLY_EXEC; + gate_vma.vm_flags = VM_READ | VM_EXEC | + VM_MAYREAD | VM_MAYEXEC | + VM_ALWAYSDUMP; + return 0; +} +arch_initcall(gate_vma_init); + +struct vm_area_struct *get_gate_vma(struct mm_struct *mm) +{ + return &gate_vma; +} + +int in_gate_area(struct mm_struct *mm, unsigned long addr) +{ + return (addr >= gate_vma.vm_start) && (addr < gate_vma.vm_end); +} + +int in_gate_area_no_mm(unsigned long addr) +{ + return in_gate_area(NULL, addr); } const char *arch_vma_name(struct vm_area_struct *vma) { - return (vma->vm_start == 0xffff0000) ? "[vectors]" : NULL; + return (vma == &gate_vma) ? "[vectors]" : NULL; } #endif |