diff options
| author | Russell King <rmk+kernel@arm.linux.org.uk> | 2012-05-16 15:19:20 +0100 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2012-05-21 10:46:18 -0700 |
| commit | 4d650fc196b3d6a600edfb7ed72ac72b47ea6185 (patch) | |
| tree | 6a6f217e8695349962be9392d6fed97adef644ff | |
| parent | a2e4e710c086666027b14bfcc4ca7c46773a7d6e (diff) | |
ARM: prevent VM_GROWSDOWN mmaps extending below FIRST_USER_ADDRESS
commit 9b61a4d1b2064dbd0c9e61754305ac852170509f upstream.
Reported-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | arch/arm/mm/fault.c | 4 |
1 files changed, 3 insertions, 1 deletions
diff --git a/arch/arm/mm/fault.c b/arch/arm/mm/fault.c index bb7eac381a8e..90e366a133e3 100644 --- a/arch/arm/mm/fault.c +++ b/arch/arm/mm/fault.c @@ -245,7 +245,9 @@ good_area: return handle_mm_fault(mm, vma, addr & PAGE_MASK, flags); check_stack: - if (vma->vm_flags & VM_GROWSDOWN && !expand_stack(vma, addr)) + /* Don't allow expansion below FIRST_USER_ADDRESS */ + if (vma->vm_flags & VM_GROWSDOWN && + addr >= FIRST_USER_ADDRESS && !expand_stack(vma, addr)) goto good_area; out: return fault; |