flush_cache_page(bprm->vma, pos, page_to_pfn(page));
}
-static int __bprm_mm_init(struct linux_binprm *bprm)
-{
- int err;
- struct vm_area_struct *vma = NULL;
- struct mm_struct *mm = bprm->mm;
-
- bprm->vma = vma = vm_area_alloc(mm);
- if (!vma)
- return -ENOMEM;
- vma_set_anonymous(vma);
-
- if (mmap_write_lock_killable(mm)) {
- err = -EINTR;
- goto err_free;
- }
-
- /*
- * Need to be called with mmap write lock
- * held, to avoid race with ksmd.
- */
- err = ksm_execve(mm);
- if (err)
- goto err_ksm;
-
- /*
- * Place the stack at the largest stack address the architecture
- * supports. Later, we'll move this to an appropriate place. We don't
- * use STACK_TOP because that can depend on attributes which aren't
- * configured yet.
- */
- BUILD_BUG_ON(VM_STACK_FLAGS & VM_STACK_INCOMPLETE_SETUP);
- vma->vm_end = STACK_TOP_MAX;
- vma->vm_start = vma->vm_end - PAGE_SIZE;
- vm_flags_init(vma, VM_SOFTDIRTY | VM_STACK_FLAGS | VM_STACK_INCOMPLETE_SETUP);
- vma->vm_page_prot = vm_get_page_prot(vma->vm_flags);
-
- err = insert_vm_struct(mm, vma);
- if (err)
- goto err;
-
- mm->stack_vm = mm->total_vm = 1;
- mmap_write_unlock(mm);
- bprm->p = vma->vm_end - sizeof(void *);
- return 0;
-err:
- ksm_exit(mm);
-err_ksm:
- mmap_write_unlock(mm);
-err_free:
- bprm->vma = NULL;
- vm_area_free(vma);
- return err;
-}
-
static bool valid_arg_len(struct linux_binprm *bprm, long len)
{
return len <= MAX_ARG_STRLEN;
{
}
-static int __bprm_mm_init(struct linux_binprm *bprm)
-{
- bprm->p = PAGE_SIZE * MAX_ARG_PAGES - sizeof(void *);
- return 0;
-}
-
static bool valid_arg_len(struct linux_binprm *bprm, long len)
{
return len <= bprm->p;
bprm->rlim_stack = current->signal->rlim[RLIMIT_STACK];
task_unlock(current->group_leader);
- err = __bprm_mm_init(bprm);
+#ifndef CONFIG_MMU
+ bprm->p = PAGE_SIZE * MAX_ARG_PAGES - sizeof(void *);
+#else
+ err = create_init_stack_vma(bprm->mm, &bprm->vma, &bprm->p);
if (err)
goto err;
+#endif
return 0;
vm_unacct_memory(nr_accounted);
}
-/* Insert vm structure into process list sorted by address
- * and into the inode's i_mmap tree. If vm_file is non-NULL
- * then i_mmap_rwsem is taken here.
- */
-int insert_vm_struct(struct mm_struct *mm, struct vm_area_struct *vma)
-{
- unsigned long charged = vma_pages(vma);
-
-
- if (find_vma_intersection(mm, vma->vm_start, vma->vm_end))
- return -ENOMEM;
-
- if ((vma->vm_flags & VM_ACCOUNT) &&
- security_vm_enough_memory_mm(mm, charged))
- return -ENOMEM;
-
- /*
- * The vm_pgoff of a purely anonymous vma should be irrelevant
- * until its first write fault, when page's anon_vma and index
- * are set. But now set the vm_pgoff it will almost certainly
- * end up with (unless mremap moves it elsewhere before that
- * first wfault), so /proc/pid/maps tells a consistent story.
- *
- * By setting it to reflect the virtual start address of the
- * vma, merges and splits can happen in a seamless way, just
- * using the existing file pgoff checks and manipulations.
- * Similarly in do_mmap and in do_brk_flags.
- */
- if (vma_is_anonymous(vma)) {
- BUG_ON(vma->anon_vma);
- vma->vm_pgoff = vma->vm_start >> PAGE_SHIFT;
- }
-
- if (vma_link(mm, vma)) {
- if (vma->vm_flags & VM_ACCOUNT)
- vm_unacct_memory(charged);
- return -ENOMEM;
- }
-
- return 0;
-}
-
/*
* Return true if the calling process may expand its vm space by the passed
* number of pages
userfaultfd_unmap_complete(mm, &uf);
return ret;
}
+
+
+/* Insert vm structure into process list sorted by address
+ * and into the inode's i_mmap tree. If vm_file is non-NULL
+ * then i_mmap_rwsem is taken here.
+ */
+int insert_vm_struct(struct mm_struct *mm, struct vm_area_struct *vma)
+{
+ unsigned long charged = vma_pages(vma);
+
+
+ if (find_vma_intersection(mm, vma->vm_start, vma->vm_end))
+ return -ENOMEM;
+
+ if ((vma->vm_flags & VM_ACCOUNT) &&
+ security_vm_enough_memory_mm(mm, charged))
+ return -ENOMEM;
+
+ /*
+ * The vm_pgoff of a purely anonymous vma should be irrelevant
+ * until its first write fault, when page's anon_vma and index
+ * are set. But now set the vm_pgoff it will almost certainly
+ * end up with (unless mremap moves it elsewhere before that
+ * first wfault), so /proc/pid/maps tells a consistent story.
+ *
+ * By setting it to reflect the virtual start address of the
+ * vma, merges and splits can happen in a seamless way, just
+ * using the existing file pgoff checks and manipulations.
+ * Similarly in do_mmap and in do_brk_flags.
+ */
+ if (vma_is_anonymous(vma)) {
+ BUG_ON(vma->anon_vma);
+ vma->vm_pgoff = vma->vm_start >> PAGE_SHIFT;
+ }
+
+ if (vma_link(mm, vma)) {
+ if (vma->vm_flags & VM_ACCOUNT)
+ vm_unacct_memory(charged);
+ return -ENOMEM;
+ }
+
+ return 0;
+}
int __vm_munmap(unsigned long start, size_t len, bool unlock);
+int insert_vm_struct(struct mm_struct *mm, struct vm_area_struct *vma);
+
/* vma_exec.c */
#ifdef CONFIG_MMU
+int create_init_stack_vma(struct mm_struct *mm, struct vm_area_struct **vmap,
+ unsigned long *top_mem_p);
int relocate_vma_down(struct vm_area_struct *vma, unsigned long shift);
#endif
/* Shrink the vma to just the new range */
return vma_shrink(&vmi, vma, new_start, new_end, vma->vm_pgoff);
}
+
+/*
+ * Establish the stack VMA in an execve'd process, located temporarily at the
+ * maximum stack address provided by the architecture.
+ *
+ * We later relocate this downwards in relocate_vma_down().
+ *
+ * This function is almost certainly NOT what you want for anything other than
+ * early executable initialisation.
+ *
+ * On success, returns 0 and sets *vmap to the stack VMA and *top_mem_p to the
+ * maximum addressable location in the stack (that is capable of storing a
+ * system word of data).
+ */
+int create_init_stack_vma(struct mm_struct *mm, struct vm_area_struct **vmap,
+ unsigned long *top_mem_p)
+{
+ int err;
+ struct vm_area_struct *vma = vm_area_alloc(mm);
+
+ if (!vma)
+ return -ENOMEM;
+
+ vma_set_anonymous(vma);
+
+ if (mmap_write_lock_killable(mm)) {
+ err = -EINTR;
+ goto err_free;
+ }
+
+ /*
+ * Need to be called with mmap write lock
+ * held, to avoid race with ksmd.
+ */
+ err = ksm_execve(mm);
+ if (err)
+ goto err_ksm;
+
+ /*
+ * Place the stack at the largest stack address the architecture
+ * supports. Later, we'll move this to an appropriate place. We don't
+ * use STACK_TOP because that can depend on attributes which aren't
+ * configured yet.
+ */
+ BUILD_BUG_ON(VM_STACK_FLAGS & VM_STACK_INCOMPLETE_SETUP);
+ vma->vm_end = STACK_TOP_MAX;
+ vma->vm_start = vma->vm_end - PAGE_SIZE;
+ vm_flags_init(vma, VM_SOFTDIRTY | VM_STACK_FLAGS | VM_STACK_INCOMPLETE_SETUP);
+ vma->vm_page_prot = vm_get_page_prot(vma->vm_flags);
+
+ err = insert_vm_struct(mm, vma);
+ if (err)
+ goto err;
+
+ mm->stack_vm = mm->total_vm = 1;
+ mmap_write_unlock(mm);
+ *vmap = vma;
+ *top_mem_p = vma->vm_end - sizeof(void *);
+ return 0;
+
+err:
+ ksm_exit(mm);
+err_ksm:
+ mmap_write_unlock(mm);
+err_free:
+ *vmap = NULL;
+ vm_area_free(vma);
+ return err;
+}
#define VM_PFNMAP 0x00000400
#define VM_LOCKED 0x00002000
#define VM_IO 0x00004000
+#define VM_SEQ_READ 0x00008000 /* App will access data sequentially */
+#define VM_RAND_READ 0x00010000 /* App will not benefit from clustered reads */
#define VM_DONTEXPAND 0x00040000
#define VM_LOCKONFAULT 0x00080000
#define VM_ACCOUNT 0x00100000
#define VM_ACCESS_FLAGS (VM_READ | VM_WRITE | VM_EXEC)
#define VM_SPECIAL (VM_IO | VM_DONTEXPAND | VM_PFNMAP | VM_MIXEDMAP)
+#ifdef CONFIG_STACK_GROWSUP
+#define VM_STACK VM_GROWSUP
+#define VM_STACK_EARLY VM_GROWSDOWN
+#else
+#define VM_STACK VM_GROWSDOWN
+#define VM_STACK_EARLY 0
+#endif
+
+#define DEFAULT_MAP_WINDOW ((1UL << 47) - PAGE_SIZE)
+#define TASK_SIZE_LOW DEFAULT_MAP_WINDOW
+#define TASK_SIZE_MAX DEFAULT_MAP_WINDOW
+#define STACK_TOP TASK_SIZE_LOW
+#define STACK_TOP_MAX TASK_SIZE_MAX
+
/* This mask represents all the VMA flag bits used by mlock */
#define VM_LOCKED_MASK (VM_LOCKED | VM_LOCKONFAULT)
#define VM_STARTGAP_FLAGS (VM_GROWSDOWN | VM_SHADOW_STACK)
+#define VM_STACK_DEFAULT_FLAGS VM_DATA_DEFAULT_FLAGS
+#define VM_STACK_FLAGS (VM_STACK | VM_STACK_DEFAULT_FLAGS | VM_ACCOUNT)
+#define VM_STACK_INCOMPLETE_SETUP (VM_RAND_READ | VM_SEQ_READ | VM_STACK_EARLY)
+
#define RLIMIT_STACK 3 /* max stack size */
#define RLIMIT_MEMLOCK 8 /* max locked-in-memory address space */
(void)ceiling;
}
+static inline int ksm_execve(struct mm_struct *mm)
+{
+ (void)mm;
+
+ return 0;
+}
+
+static inline void ksm_exit(struct mm_struct *mm)
+{
+ (void)mm;
+}
+
#endif /* __MM_VMA_INTERNAL_H */
projects / thirdparty / linux.git / commitdiff
