[AppArmor 13/44] Pass the struct vfsmounts to the inode_link LSM hook

[jjohansen@suse.de]

[-- Attachment #1: security-link.diff --]
[-- Type: text/plain, Size: 4246 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/namei.c               |    3 ++-
 include/linux/security.h |   18 +++++++++++++-----
 security/dummy.c         |    6 ++++--
 security/selinux/hooks.c |    9 +++++++--
 4 files changed, 26 insertions(+), 10 deletions(-)

--- a/fs/namei.c
+++ b/fs/namei.c
@@ -2293,7 +2293,8 @@ int vfs_link(struct dentry *old_dentry, 
 	if (S_ISDIR(old_dentry->d_inode->i_mode))
 		return -EPERM;
 
-	error = security_inode_link(old_dentry, dir, new_dentry);
+	error = security_inode_link(old_dentry, old_mnt, dir, new_dentry,
+				    new_mnt);
 	if (error)
 		return error;
 
--- a/include/linux/security.h
+++ b/include/linux/security.h
@@ -289,8 +289,10 @@ struct request_sock;
  * @inode_link:
  *	Check permission before creating a new hard link to a file.
  *	@old_dentry contains the dentry structure for an existing link to the file.
+ *	@old_mnt is the vfsmount corresponding to @old_dentry (may be NULL).
  *	@dir contains the inode structure of the parent directory of the new link.
  *	@new_dentry contains the dentry structure for the new link.
+ *	@new_mnt is the vfsmount corresponding to @new_dentry (may be NULL).
  *	Return 0 if permission is granted.
  * @inode_unlink:
  *	Check the permission to remove a hard link to a file. 
@@ -1212,8 +1214,9 @@ struct security_operations {
 				    char **name, void **value, size_t *len);
 	int (*inode_create) (struct inode *dir, struct dentry *dentry,
 			     struct vfsmount *mnt, int mode);
-	int (*inode_link) (struct dentry *old_dentry,
-	                   struct inode *dir, struct dentry *new_dentry);
+	int (*inode_link) (struct dentry *old_dentry, struct vfsmount *old_mnt,
+	                   struct inode *dir, struct dentry *new_dentry,
+			   struct vfsmount *new_mnt);
 	int (*inode_unlink) (struct inode *dir, struct dentry *dentry);
 	int (*inode_symlink) (struct inode *dir, struct dentry *dentry,
 			      struct vfsmount *mnt, const char *old_name);
@@ -1628,12 +1631,15 @@ static inline int security_inode_create 
 }
 
 static inline int security_inode_link (struct dentry *old_dentry,
+				       struct vfsmount *old_mnt,
 				       struct inode *dir,
-				       struct dentry *new_dentry)
+				       struct dentry *new_dentry,
+				       struct vfsmount *new_mnt)
 {
 	if (unlikely (IS_PRIVATE (old_dentry->d_inode)))
 		return 0;
-	return security_ops->inode_link (old_dentry, dir, new_dentry);
+	return security_ops->inode_link (old_dentry, old_mnt, dir,
+					 new_dentry, new_mnt);
 }
 
 static inline int security_inode_unlink (struct inode *dir,
@@ -2359,8 +2365,10 @@ static inline int security_inode_create 
 }
 
 static inline int security_inode_link (struct dentry *old_dentry,
+				       struct vfsmount *old_mnt,
 				       struct inode *dir,
-				       struct dentry *new_dentry)
+				       struct dentry *new_dentry,
+				       struct vfsmount *new_mnt)
 {
 	return 0;
 }
--- a/security/dummy.c
+++ b/security/dummy.c
@@ -270,8 +270,10 @@ static int dummy_inode_create (struct in
 	return 0;
 }
 
-static int dummy_inode_link (struct dentry *old_dentry, struct inode *inode,
-			     struct dentry *new_dentry)
+static int dummy_inode_link (struct dentry *old_dentry,
+			     struct vfsmount *old_mnt, struct inode *inode,
+			     struct dentry *new_dentry,
+			     struct vfsmount *new_mnt)
 {
 	return 0;
 }
--- a/security/selinux/hooks.c
+++ b/security/selinux/hooks.c
@@ -2182,11 +2182,16 @@ static int selinux_inode_create(struct i
 	return may_create(dir, dentry, SECCLASS_FILE);
 }
 
-static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry)
+static int selinux_inode_link(struct dentry *old_dentry,
+			      struct vfsmount *old_mnt,
+			      struct inode *dir,
+			      struct dentry *new_dentry,
+			      struct vfsmount *new_mnt)
 {
 	int rc;
 
-	rc = secondary_ops->inode_link(old_dentry,dir,new_dentry);
+	rc = secondary_ops->inode_link(old_dentry, old_mnt, dir, new_dentry,
+				       new_mnt);
 	if (rc)
 		return rc;
 	return may_link(dir, old_dentry, MAY_LINK);

--