Merge tag 'media/v4.17-4' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab...

[linux.git] / mm / mmap.c

diff --git a/mm/mmap.c b/mm/mmap.c
index f2154fc2548b0e13e7e2a61b86e5720765260d1f..9d5968d1e8e3360ecd1dd9a095139090a1a1f107 100644 (file)
--- a/mm/mmap.c
+++ b/mm/mmap.c
@@ -100,11 +100,20 @@ pgprot_t protection_map[16] __ro_after_init = {
        __S000, __S001, __S010, __S011, __S100, __S101, __S110, __S111
 };
 
+#ifndef CONFIG_ARCH_HAS_FILTER_PGPROT
+static inline pgprot_t arch_filter_pgprot(pgprot_t prot)
+{
+       return prot;
+}
+#endif
+
 pgprot_t vm_get_page_prot(unsigned long vm_flags)
 {
-       return __pgprot(pgprot_val(protection_map[vm_flags &
+       pgprot_t ret = __pgprot(pgprot_val(protection_map[vm_flags &
                                (VM_READ|VM_WRITE|VM_EXEC|VM_SHARED)]) |
                        pgprot_val(arch_vm_get_page_prot(vm_flags)));
+
+       return arch_filter_pgprot(ret);
 }
 EXPORT_SYMBOL(vm_get_page_prot);
 
@@ -1342,6 +1351,10 @@ unsigned long do_mmap(struct file *file, unsigned long addr,
                if (!(file && path_noexec(&file->f_path)))
                        prot |= PROT_EXEC;
 
+       /* force arch specific MAP_FIXED handling in get_unmapped_area */
+       if (flags & MAP_FIXED_NOREPLACE)
+               flags |= MAP_FIXED;
+
        if (!(flags & MAP_FIXED))
                addr = round_hint_to_min(addr);
 
@@ -1365,6 +1378,13 @@ unsigned long do_mmap(struct file *file, unsigned long addr,
        if (offset_in_page(addr))
                return addr;
 
+       if (flags & MAP_FIXED_NOREPLACE) {
+               struct vm_area_struct *vma = find_vma(mm, addr);
+
+               if (vma && vma->vm_start <= addr)
+                       return -EEXIST;
+       }
+
        if (prot == PROT_EXEC) {
                pkey = execute_only_pkey(mm);
                if (pkey < 0)