[PATCH 4/8] user ns: hook permission

[Serge E. Hallyn]

From: Serge E. Hallyn <serue at us.ibm.com>
Subject: [PATCH 4/8] user ns: hook permission

Hook permission to check vfsmnt->user_ns against current.

Signed-off-by: Serge E. Hallyn <serue at us.ibm.com>
---
 fs/namei.c |    4 ++++
 1 files changed, 4 insertions(+), 0 deletions(-)

diff --git a/fs/namei.c b/fs/namei.c
index e4f108f..d6687af 100644
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -246,6 +246,8 @@ int permission(struct inode *inode, int 
 			return -EACCES;
 	}
 
+	if (nd && !task_mnt_same_uidns(current, nd->mnt))
+		return -EACCES;
 
 	/*
 	 * MAY_EXEC on regular files requires special handling: We override
@@ -433,6 +435,8 @@ static int exec_permission_lite(struct i
 {
 	umode_t	mode = inode->i_mode;
 
+	if (!task_mnt_same_uidns(current, nd->mnt))
+		return -EACCES;
 	if (inode->i_op && inode->i_op->permission)
 		return -EAGAIN;
 
-- 
1.4.1