proc: Pass file mode to proc_pid_make_inode

Pass the file mode of the proc inode to be created to
proc_pid_make_inode.  In proc_pid_make_inode, initialize inode->i_mode
before calling security_task_to_inode.  This allows selinux to set
isec->sclass right away without introducing "half-initialized" inode
security structs.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>

4 files changed, 13 insertions, 21 deletions

diff --git a/fs/proc/base.c b/fs/proc/base.c
index 8e654468ab67..9de05e5854ef 100644
--- a/fs/proc/base.c
+++ b/fs/proc/base.c
@@ -1663,7 +1663,8 @@ const struct inode_operations proc_pid_link_inode_operations = {
 
 /* building an inode */
 
-struct inode *proc_pid_make_inode(struct super_block * sb, struct task_struct *task)
+struct inode *proc_pid_make_inode(struct super_block * sb,
+                                  struct task_struct *task, umode_t mode)
 {
         struct inode * inode;
         struct proc_inode *ei;
@@ -1677,6 +1678,7 @@ struct inode *proc_pid_make_inode(struct super_block * sb, struct task_struct *t
 
         /* Common stuff */
         ei = PROC_I(inode);
+        inode->i_mode = mode;
         inode->i_ino = get_next_ino();
         inode->i_mtime = inode->i_atime = inode->i_ctime = current_time(inode);
         inode->i_op = &proc_def_inode_operations;
@@ -2003,7 +2005,9 @@ proc_map_files_instantiate(struct inode *dir, struct dentry *dentry,
         struct proc_inode *ei;
         struct inode *inode;
 
-        inode = proc_pid_make_inode(dir->i_sb, task);
+        inode = proc_pid_make_inode(dir->i_sb, task, S_IFLNK |
+                                    ((mode & FMODE_READ ) ? S_IRUSR : 0) |
+                                    ((mode & FMODE_WRITE) ? S_IWUSR : 0));
         if (!inode)
                 return -ENOENT;
 
@@ -2012,12 +2016,6 @@ proc_map_files_instantiate(struct inode *dir, struct dentry *dentry,
 
         inode->i_op = &proc_map_files_link_inode_operations;
         inode->i_size = 64;
-        inode->i_mode = S_IFLNK;
-
-        if (mode & FMODE_READ)
-                inode->i_mode |= S_IRUSR;
-        if (mode & FMODE_WRITE)
-                inode->i_mode |= S_IWUSR;
 
         d_set_d_op(dentry, &tid_map_files_dentry_operations);
         d_add(dentry, inode);
@@ -2371,12 +2369,11 @@ static int proc_pident_instantiate(struct inode *dir,
         struct inode *inode;
         struct proc_inode *ei;
 
-        inode = proc_pid_make_inode(dir->i_sb, task);
+        inode = proc_pid_make_inode(dir->i_sb, task, p->mode);
         if (!inode)
                 goto out;
 
         ei = PROC_I(inode);
-        inode->i_mode = p->mode;
         if (S_ISDIR(inode->i_mode))
                 set_nlink(inode, 2);    /* Use getattr to fix if necessary */
         if (p->iop)
@@ -3058,11 +3055,10 @@ static int proc_pid_instantiate(struct inode *dir,
 {
         struct inode *inode;
 
-        inode = proc_pid_make_inode(dir->i_sb, task);
+        inode = proc_pid_make_inode(dir->i_sb, task, S_IFDIR | S_IRUGO | S_IXUGO);
         if (!inode)
                 goto out;
 
-        inode->i_mode = S_IFDIR|S_IRUGO|S_IXUGO;
         inode->i_op = &proc_tgid_base_inode_operations;
         inode->i_fop = &proc_tgid_base_operations;
         inode->i_flags|=S_IMMUTABLE;
@@ -3351,11 +3347,10 @@ static int proc_task_instantiate(struct inode *dir,
         struct dentry *dentry, struct task_struct *task, const void *ptr)
 {
         struct inode *inode;
-        inode = proc_pid_make_inode(dir->i_sb, task);
+        inode = proc_pid_make_inode(dir->i_sb, task, S_IFDIR | S_IRUGO | S_IXUGO);
 
         if (!inode)
                 goto out;
-        inode->i_mode = S_IFDIR|S_IRUGO|S_IXUGO;
         inode->i_op = &proc_tid_base_inode_operations;
         inode->i_fop = &proc_tid_base_operations;
         inode->i_flags|=S_IMMUTABLE;
diff --git a/fs/proc/fd.c b/fs/proc/fd.c
index d21dafef3102..4274f83bf100 100644
--- a/fs/proc/fd.c
+++ b/fs/proc/fd.c
@@ -183,14 +183,13 @@ proc_fd_instantiate(struct inode *dir, struct dentry *dentry,
         struct proc_inode *ei;
         struct inode *inode;
 
-        inode = proc_pid_make_inode(dir->i_sb, task);
+        inode = proc_pid_make_inode(dir->i_sb, task, S_IFLNK);
         if (!inode)
                 goto out;
 
         ei = PROC_I(inode);
         ei->fd = fd;
 
-        inode->i_mode = S_IFLNK;
         inode->i_op = &proc_pid_link_inode_operations;
         inode->i_size = 64;
 
@@ -322,14 +321,13 @@ proc_fdinfo_instantiate(struct inode *dir, struct dentry *dentry,
         struct proc_inode *ei;
         struct inode *inode;
 
-        inode = proc_pid_make_inode(dir->i_sb, task);
+        inode = proc_pid_make_inode(dir->i_sb, task, S_IFREG | S_IRUSR);
         if (!inode)
                 goto out;
 
         ei = PROC_I(inode);
         ei->fd = fd;
 
-        inode->i_mode = S_IFREG | S_IRUSR;
         inode->i_fop = &proc_fdinfo_file_operations;
 
         d_set_d_op(dentry, &tid_fd_dentry_operations);
diff --git a/fs/proc/internal.h b/fs/proc/internal.h
index 5378441ec1b7..f4494dcbdc8b 100644
--- a/fs/proc/internal.h
+++ b/fs/proc/internal.h
@@ -162,7 +162,7 @@ extern int proc_pid_statm(struct seq_file *, struct pid_namespace *,
 extern const struct dentry_operations pid_dentry_operations;
 extern int pid_getattr(struct vfsmount *, struct dentry *, struct kstat *);
 extern int proc_setattr(struct dentry *, struct iattr *);
-extern struct inode *proc_pid_make_inode(struct super_block *, struct task_struct *);
+extern struct inode *proc_pid_make_inode(struct super_block *, struct task_struct *, umode_t);
 extern int pid_revalidate(struct dentry *, unsigned int);
 extern int pid_delete_dentry(const struct dentry *);
 extern int proc_pid_readdir(struct file *, struct dir_context *);
diff --git a/fs/proc/namespaces.c b/fs/proc/namespaces.c
index 51b8b0a8ad91..766f0c637ad1 100644
--- a/fs/proc/namespaces.c
+++ b/fs/proc/namespaces.c
@@ -92,12 +92,11 @@ static int proc_ns_instantiate(struct inode *dir,
         struct inode *inode;
         struct proc_inode *ei;
 
-        inode = proc_pid_make_inode(dir->i_sb, task);
+        inode = proc_pid_make_inode(dir->i_sb, task, S_IFLNK | S_IRWXUGO);
         if (!inode)
                 goto out;
 
         ei = PROC_I(inode);
-        inode->i_mode = S_IFLNK|S_IRWXUGO;
         inode->i_op = &proc_ns_link_inode_operations;
         ei->ns_ops = ns_ops;