Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/selinux-2.6

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/selinux-2.6:
  VM/Security: add security hook to do_brk
  Security: round mmap hint address above mmap_min_addr
  security: protect from stack expantion into low vm addresses
  Security: allow capable check to permit mmap or low vm space
  SELinux: detect dead booleans
  SELinux: do not clear f_op when removing entries

2 files changed, 12 insertions, 2 deletions

diff --git a/mm/mmap.c b/mm/mmap.c
index acfc13f23ca0..15678aa6ec73 100644
--- a/mm/mmap.c
+++ b/mm/mmap.c
@@ -912,6 +912,9 @@ unsigned long do_mmap_pgoff(struct file * file, unsigned long addr,
 	if (!len)
 		return -EINVAL;
 
+	if (!(flags & MAP_FIXED))
+		addr = round_hint_to_min(addr);
+
 	error = arch_mmap_check(addr, len, flags);
 	if (error)
 		return error;
@@ -1615,6 +1618,12 @@ static inline int expand_downwards(struct vm_area_struct *vma,
 	 */
 	if (unlikely(anon_vma_prepare(vma)))
 		return -ENOMEM;
+
+	address &= PAGE_MASK;
+	error = security_file_mmap(0, 0, 0, 0, address, 1);
+	if (error)
+		return error;
+
 	anon_vma_lock(vma);
 
 	/*
@@ -1622,8 +1631,6 @@ static inline int expand_downwards(struct vm_area_struct *vma,
 	 * is required to hold the mmap_sem in read mode.  We need the
 	 * anon_vma lock to serialize against concurrent expand_stacks.
 	 */
-	address &= PAGE_MASK;
-	error = 0;
 
 	/* Somebody else might have raced and expanded it already */
 	if (address < vma->vm_start) {
diff --git a/mm/nommu.c b/mm/nommu.c
index 35622c590925..b989cb928a7c 100644
--- a/mm/nommu.c
+++ b/mm/nommu.c
@@ -829,6 +829,9 @@ 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,