sparc: Fix mremap address range validation.

Just like mmap, we need to validate address ranges regardless
of MAP_FIXED.

sparc{,64}_mmap_check()'s flag argument is unused, remove.

Based upon a report and preliminary patch by
Jan Lieskovsky <jlieskov@redhat.com>

Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 2 insertions, 31 deletions

diff --git a/arch/sparc64/kernel/sys_sparc32.c b/arch/sparc64/kernel/sys_sparc32.c
index 1aa4288125f2..ba5bd626b39e 100644
--- a/arch/sparc64/kernel/sys_sparc32.c
+++ b/arch/sparc64/kernel/sys_sparc32.c
@@ -867,44 +867,15 @@ asmlinkage unsigned long sys32_mremap(unsigned long addr,
         unsigned long old_len, unsigned long new_len,
         unsigned long flags, u32 __new_addr)
 {
-        struct vm_area_struct *vma;
         unsigned long ret = -EINVAL;
         unsigned long new_addr = __new_addr;
 
-        if (old_len > STACK_TOP32 || new_len > STACK_TOP32)
+        if (unlikely(sparc64_mmap_check(addr, old_len)))
                 goto out;
-        if (addr > STACK_TOP32 - old_len)
+        if (unlikely(sparc64_mmap_check(new_addr, new_len)))
                 goto out;
         down_write(&current->mm->mmap_sem);
-        if (flags & MREMAP_FIXED) {
-                if (new_addr > STACK_TOP32 - new_len)
-                        goto out_sem;
-        } else if (addr > STACK_TOP32 - new_len) {
-                unsigned long map_flags = 0;
-                struct file *file = NULL;
-
-                ret = -ENOMEM;
-                if (!(flags & MREMAP_MAYMOVE))
-                        goto out_sem;
-
-                vma = find_vma(current->mm, addr);
-                if (vma) {
-                        if (vma->vm_flags & VM_SHARED)
-                                map_flags |= MAP_SHARED;
-                        file = vma->vm_file;
-                }
-
-                /* MREMAP_FIXED checked above. */
-                new_addr = get_unmapped_area(file, addr, new_len,
-                                    vma ? vma->vm_pgoff : 0,
-                                    map_flags);
-                ret = new_addr;
-                if (new_addr & ~PAGE_MASK)
-                        goto out_sem;
-                flags |= MREMAP_FIXED;
-        }
         ret = do_mremap(addr, old_len, new_len, flags, new_addr);
-out_sem:
         up_write(&current->mm->mmap_sem);
 out:
         return ret;