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 1aa4288125f..ba5bd626b39 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;