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 09:40:01 -0700 |
commit | dbda13fc2193061009cd20998f64dd01a97309a9 (patch) | |
tree | a3b0ebbf5aae3e6e9c972604288acf444ea7453f /arch/arm | |
parent | 1c1cb5756a8d296bbc33fc844f97048dc09ee172 (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>
Diffstat (limited to 'arch/arm')
-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 bc0e1d88fd3b..8799eae5da9b 100644 --- a/arch/arm/mm/fault.c +++ b/arch/arm/mm/fault.c @@ -266,7 +266,9 @@ good_area: return fault; 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; |