]> pilppa.org Git - linux-2.6-omap-h63xx.git/blobdiff - mm/nommu.c
Security: Typecast CAP_*_SET macros
[linux-2.6-omap-h63xx.git] / mm / nommu.c
index 8f09333f78e1d63dbe1a5d24c9ba240ce683dbc6..ef8c62cec697a06495b13f2658aff4e30000065c 100644 (file)
  *  Copyright (c) 2000-2003 David McCullough <davidm@snapgear.com>
  *  Copyright (c) 2000-2001 D Jeff Dionne <jeff@uClinux.org>
  *  Copyright (c) 2002      Greg Ungerer <gerg@snapgear.com>
+ *  Copyright (c) 2007      Paul Mundt <lethal@linux-sh.org>
  */
 
+#include <linux/module.h>
 #include <linux/mm.h>
 #include <linux/mman.h>
 #include <linux/swap.h>
@@ -103,7 +105,11 @@ unsigned int kobjsize(const void *objp)
 {
        struct page *page;
 
-       if (!objp || !((page = virt_to_page(objp))))
+       /*
+        * If the object we have should not have ksize performed on it,
+        * return size of 0
+        */
+       if (!objp || (unsigned long)objp >= memory_end || !((page = virt_to_page(objp))))
                return 0;
 
        if (PageSlab(page))
@@ -166,7 +172,7 @@ EXPORT_SYMBOL(get_user_pages);
 DEFINE_RWLOCK(vmlist_lock);
 struct vm_struct *vmlist;
 
-void vfree(void *addr)
+void vfree(const void *addr)
 {
        kfree(addr);
 }
@@ -182,13 +188,33 @@ void *__vmalloc(unsigned long size, gfp_t gfp_mask, pgprot_t prot)
 }
 EXPORT_SYMBOL(__vmalloc);
 
-struct page * vmalloc_to_page(void *addr)
+void *vmalloc_user(unsigned long size)
+{
+       void *ret;
+
+       ret = __vmalloc(size, GFP_KERNEL | __GFP_HIGHMEM | __GFP_ZERO,
+                       PAGE_KERNEL);
+       if (ret) {
+               struct vm_area_struct *vma;
+
+               down_write(&current->mm->mmap_sem);
+               vma = find_vma(current->mm, (unsigned long)ret);
+               if (vma)
+                       vma->vm_flags |= VM_USERMAP;
+               up_write(&current->mm->mmap_sem);
+       }
+
+       return ret;
+}
+EXPORT_SYMBOL(vmalloc_user);
+
+struct page *vmalloc_to_page(const void *addr)
 {
        return virt_to_page(addr);
 }
 EXPORT_SYMBOL(vmalloc_to_page);
 
-unsigned long vmalloc_to_pfn(void *addr)
+unsigned long vmalloc_to_pfn(const void *addr)
 {
        return page_to_pfn(virt_to_page(addr));
 }
@@ -252,10 +278,17 @@ EXPORT_SYMBOL(vmalloc_32);
  *
  * The resulting memory area is 32bit addressable and zeroed so it can be
  * mapped to userspace without leaking data.
+ *
+ * VM_USERMAP is set on the corresponding VMA so that subsequent calls to
+ * remap_vmalloc_range() are permissible.
  */
 void *vmalloc_32_user(unsigned long size)
 {
-       return __vmalloc(size, GFP_KERNEL | __GFP_ZERO, PAGE_KERNEL);
+       /*
+        * We'll have to sort out the ZONE_DMA bits for 64-bit,
+        * but for now this can simply use vmalloc_user() directly.
+        */
+       return vmalloc_user(size);
 }
 EXPORT_SYMBOL(vmalloc_32_user);
 
@@ -266,7 +299,7 @@ void *vmap(struct page **pages, unsigned int count, unsigned long flags, pgprot_
 }
 EXPORT_SYMBOL(vmap);
 
-void vunmap(void *addr)
+void vunmap(const void *addr)
 {
        BUG();
 }
@@ -828,6 +861,9 @@ unsigned long do_mmap_pgoff(struct file *file,
        void *result;
        int ret;
 
+       if (!(flags & MAP_FIXED))
+               addr = round_hint_to_min(addr);
+
        /* decide whether we should attempt the mapping, and if so what sort of
         * mapping */
        ret = validate_mmap_request(file, addr, len, prot, flags, pgoff,
@@ -930,8 +966,13 @@ unsigned long do_mmap_pgoff(struct file *file,
 
        INIT_LIST_HEAD(&vma->anon_vma_node);
        atomic_set(&vma->vm_usage, 1);
-       if (file)
+       if (file) {
                get_file(file);
+               if (vm_flags & VM_EXECUTABLE) {
+                       added_exe_file_vma(current->mm);
+                       vma->vm_mm = current->mm;
+               }
+       }
        vma->vm_file    = file;
        vma->vm_flags   = vm_flags;
        vma->vm_start   = addr;
@@ -986,8 +1027,11 @@ unsigned long do_mmap_pgoff(struct file *file,
        up_write(&nommu_vma_sem);
        kfree(vml);
        if (vma) {
-               if (vma->vm_file)
+               if (vma->vm_file) {
                        fput(vma->vm_file);
+                       if (vma->vm_flags & VM_EXECUTABLE)
+                               removed_exe_file_vma(vma->vm_mm);
+               }
                kfree(vma);
        }
        return ret;
@@ -1017,7 +1061,7 @@ EXPORT_SYMBOL(do_mmap_pgoff);
 /*
  * handle mapping disposal for uClinux
  */
-static void put_vma(struct vm_area_struct *vma)
+static void put_vma(struct mm_struct *mm, struct vm_area_struct *vma)
 {
        if (vma) {
                down_write(&nommu_vma_sem);
@@ -1039,8 +1083,11 @@ static void put_vma(struct vm_area_struct *vma)
                        realalloc -= kobjsize(vma);
                        askedalloc -= sizeof(*vma);
 
-                       if (vma->vm_file)
+                       if (vma->vm_file) {
                                fput(vma->vm_file);
+                               if (vma->vm_flags & VM_EXECUTABLE)
+                                       removed_exe_file_vma(mm);
+                       }
                        kfree(vma);
                }
 
@@ -1077,7 +1124,7 @@ int do_munmap(struct mm_struct *mm, unsigned long addr, size_t len)
  found:
        vml = *parent;
 
-       put_vma(vml->vma);
+       put_vma(mm, vml->vma);
 
        *parent = vml->next;
        realalloc -= kobjsize(vml);
@@ -1122,7 +1169,7 @@ void exit_mmap(struct mm_struct * mm)
 
                while ((tmp = mm->context.vmlist)) {
                        mm->context.vmlist = tmp->next;
-                       put_vma(tmp->vma);
+                       put_vma(mm, tmp->vma);
 
                        realalloc -= kobjsize(tmp);
                        askedalloc -= sizeof(*tmp);
@@ -1212,6 +1259,21 @@ int remap_pfn_range(struct vm_area_struct *vma, unsigned long from,
 }
 EXPORT_SYMBOL(remap_pfn_range);
 
+int remap_vmalloc_range(struct vm_area_struct *vma, void *addr,
+                       unsigned long pgoff)
+{
+       unsigned int size = vma->vm_end - vma->vm_start;
+
+       if (!(vma->vm_flags & VM_USERMAP))
+               return -EINVAL;
+
+       vma->vm_start = (unsigned long)(addr + (pgoff << PAGE_SHIFT));
+       vma->vm_end = vma->vm_start + size;
+
+       return 0;
+}
+EXPORT_SYMBOL(remap_vmalloc_range);
+
 void swap_unplug_io_fn(struct backing_dev_info *bdi, struct page *page)
 {
 }