[AppArmor 13/41] Pass struct vfsmount to the inode_readlink LSM hook

jjohansen
2007-04-12T09:51:48Z

[-- Attachment #1: security-readlink.diff --]
[-- Type: text/plain, Size: 3282 bytes --]

This is needed for computing pathnames in the AppArmor LSM.

Signed-off-by: Tony Jones <tonyj@suse.de>
Signed-off-by: Andreas Gruenbacher <agruen@suse.de>
Signed-off-by: John Johansen <jjohansen@suse.de>

---
fs/stat.c | 2 +-
include/linux/security.h | 11 +++++++----
security/dummy.c | 2 +-
security/selinux/hooks.c | 2 +-
4 files changed, 10 insertions(+), 7 deletions(-)

--- a/fs/stat.c
+++ b/fs/stat.c
@@ -307,7 +307,7 @@ asmlinkage long sys_readlinkat(int dfd,

error = -EINVAL;
if (inode->i_op && inode->i_op->readlink) {
- error = security_inode_readlink(nd.dentry);
+ error = security_inode_readlink(nd.dentry, nd.mnt);
if (!error) {
touch_atime(nd.mnt, nd.dentry);
error = inode->i_op->readlink(nd.dentry, buf, bufsiz);
--- a/include/linux/security.h
+++ b/include/linux/security.h
@@ -338,6 +338,7 @@ struct request_sock;
* @inode_readlink:
* Check the permission to read the symbolic link.
* @dentry contains the dentry structure for the file link.
+ * @mnt is the vfsmount corresponding to @dentry (may be NULL).
* Return 0 if permission is granted.
* @inode_follow_link:
* Check permission to follow a symbolic link when looking up a pathname.
@@ -1223,7 +1224,7 @@ struct security_operations {
struct vfsmount *mnt, int mode, dev_t dev);
int (*inode_rename) (struct inode *old_dir, struct dentry *old_dentry,
struct inode *new_dir, struct dentry *new_dentry);
- int (*inode_readlink) (struct dentry *dentry);
+ int (*inode_readlink) (struct dentry *dentry, struct vfsmount *mnt);
int (*inode_follow_link) (struct dentry *dentry, struct nameidata *nd);
int (*inode_permission) (struct inode *inode, int mask, struct nameidata *nd);
int (*inode_setattr) (struct dentry *dentry, struct vfsmount *mnt,
@@ -1693,11 +1694,12 @@ static inline int security_inode_rename
new_dir, new_dentry);
}

-static inline int security_inode_readlink (struct dentry *dentry)
+static inline int security_inode_readlink (struct dentry *dentry,
+ struct vfsmount *mnt)
{
if (unlikely (IS_PRIVATE (dentry->d_inode)))
return 0;
- return security_ops->inode_readlink (dentry);
+ return security_ops->inode_readlink (dentry, mnt);
}

static inline int security_inode_follow_link (struct dentry *dentry,
@@ -2407,7 +2409,8 @@ static inline int security_inode_rename
return 0;
}

-static inline int security_inode_readlink (struct dentry *dentry)
+static inline int security_inode_readlink (struct dentry *dentry,
+ struct vfsmount *mnt)
{
return 0;
}
--- a/security/dummy.c
+++ b/security/dummy.c
@@ -312,7 +312,7 @@ static int dummy_inode_rename (struct in
return 0;
}

-static int dummy_inode_readlink (struct dentry *dentry)
+static int dummy_inode_readlink (struct dentry *dentry, struct vfsmount *mnt)
{
return 0;
}
--- a/security/selinux/hooks.c
+++ b/security/selinux/hooks.c
@@ -2239,7 +2239,7 @@ static int selinux_inode_rename(struct i
return may_rename(old_inode, old_dentry, new_inode, new_dentry);
}

-static int selinux_inode_readlink(struct dentry *dentry)
+static int selinux_inode_readlink(struct dentry *dentry, struct vfsmount *mnt)
{
return dentry_has_perm(current, NULL, dentry, FILE__READ);
}

--