btrfs: switch to discard_new_inode()

Make sure that no partially set up inodes can be returned by
open-by-handle.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

1 files changed, 39 insertions, 67 deletions

diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index e9482f0db9d0..9382e0881900 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -6335,8 +6335,10 @@ static struct inode *btrfs_new_inode(struct btrfs_trans_handle *trans,
         location->type = BTRFS_INODE_ITEM_KEY;
 
         ret = btrfs_insert_inode_locked(inode);
-        if (ret < 0)
+        if (ret < 0) {
+                iput(inode);
                 goto fail;
+        }
 
         path->leave_spinning = 1;
         ret = btrfs_insert_empty_items(trans, root, path, key, sizes, nitems);
@@ -6395,12 +6397,11 @@ static struct inode *btrfs_new_inode(struct btrfs_trans_handle *trans,
         return inode;
 
 fail_unlock:
-        unlock_new_inode(inode);
+        discard_new_inode(inode);
 fail:
         if (dir && name)
                 BTRFS_I(dir)->index_cnt--;
         btrfs_free_path(path);
-        iput(inode);
         return ERR_PTR(ret);
 }
 
@@ -6505,7 +6506,6 @@ static int btrfs_mknod(struct inode *dir, struct dentry *dentry,
         struct btrfs_root *root = BTRFS_I(dir)->root;
         struct inode *inode = NULL;
         int err;
-        int drop_inode = 0;
         u64 objectid;
         u64 index = 0;
 
@@ -6527,6 +6527,7 @@ static int btrfs_mknod(struct inode *dir, struct dentry *dentry,
                         mode, &index);
         if (IS_ERR(inode)) {
                 err = PTR_ERR(inode);
+                inode = NULL;
                 goto out_unlock;
         }
 
@@ -6541,31 +6542,24 @@ static int btrfs_mknod(struct inode *dir, struct dentry *dentry,
 
         err = btrfs_init_inode_security(trans, inode, dir, &dentry->d_name);
         if (err)
-                goto out_unlock_inode;
+                goto out_unlock;
 
         err = btrfs_add_nondir(trans, BTRFS_I(dir), dentry, BTRFS_I(inode),
                         0, index);
-        if (err) {
-                goto out_unlock_inode;
-        } else {
-                btrfs_update_inode(trans, root, inode);
-                d_instantiate_new(dentry, inode);
-        }
+        if (err)
+                goto out_unlock;
+
+        btrfs_update_inode(trans, root, inode);
+        d_instantiate_new(dentry, inode);
 
 out_unlock:
         btrfs_end_transaction(trans);
         btrfs_btree_balance_dirty(fs_info);
-        if (drop_inode) {
+        if (err && inode) {
                 inode_dec_link_count(inode);
-                iput(inode);
+                discard_new_inode(inode);
         }
         return err;
-
-out_unlock_inode:
-        drop_inode = 1;
-        unlock_new_inode(inode);
-        goto out_unlock;
-
 }
 
 static int btrfs_create(struct inode *dir, struct dentry *dentry,
@@ -6575,7 +6569,6 @@ static int btrfs_create(struct inode *dir, struct dentry *dentry,
         struct btrfs_trans_handle *trans;
         struct btrfs_root *root = BTRFS_I(dir)->root;
         struct inode *inode = NULL;
-        int drop_inode_on_err = 0;
         int err;
         u64 objectid;
         u64 index = 0;
@@ -6598,9 +6591,9 @@ static int btrfs_create(struct inode *dir, struct dentry *dentry,
                         mode, &index);
         if (IS_ERR(inode)) {
                 err = PTR_ERR(inode);
+                inode = NULL;
                 goto out_unlock;
         }
-        drop_inode_on_err = 1;
         /*
         * If the active LSM wants to access the inode during
         * d_instantiate it needs these. Smack checks to see
@@ -6613,33 +6606,28 @@ static int btrfs_create(struct inode *dir, struct dentry *dentry,
 
         err = btrfs_init_inode_security(trans, inode, dir, &dentry->d_name);
         if (err)
-                goto out_unlock_inode;
+                goto out_unlock;
 
         err = btrfs_update_inode(trans, root, inode);
         if (err)
-                goto out_unlock_inode;
+                goto out_unlock;
 
         err = btrfs_add_nondir(trans, BTRFS_I(dir), dentry, BTRFS_I(inode),
                         0, index);
         if (err)
-                goto out_unlock_inode;
+                goto out_unlock;
 
         BTRFS_I(inode)->io_tree.ops = &btrfs_extent_io_ops;
         d_instantiate_new(dentry, inode);
 
 out_unlock:
         btrfs_end_transaction(trans);
-        if (err && drop_inode_on_err) {
+        if (err && inode) {
                 inode_dec_link_count(inode);
-                iput(inode);
+                discard_new_inode(inode);
         }
         btrfs_btree_balance_dirty(fs_info);
         return err;
-
-out_unlock_inode:
-        unlock_new_inode(inode);
-        goto out_unlock;
-
 }
 
 static int btrfs_link(struct dentry *old_dentry, struct inode *dir,
@@ -6748,6 +6736,7 @@ static int btrfs_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
                         S_IFDIR | mode, &index);
         if (IS_ERR(inode)) {
                 err = PTR_ERR(inode);
+                inode = NULL;
                 goto out_fail;
         }
 
@@ -6758,34 +6747,30 @@ static int btrfs_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
 
         err = btrfs_init_inode_security(trans, inode, dir, &dentry->d_name);
         if (err)
-                goto out_fail_inode;
+                goto out_fail;
 
         btrfs_i_size_write(BTRFS_I(inode), 0);
         err = btrfs_update_inode(trans, root, inode);
         if (err)
-                goto out_fail_inode;
+                goto out_fail;
 
         err = btrfs_add_link(trans, BTRFS_I(dir), BTRFS_I(inode),
                         dentry->d_name.name,
                         dentry->d_name.len, 0, index);
         if (err)
-                goto out_fail_inode;
+                goto out_fail;
 
         d_instantiate_new(dentry, inode);
         drop_on_err = 0;
 
 out_fail:
         btrfs_end_transaction(trans);
-        if (drop_on_err) {
+        if (err && inode) {
                 inode_dec_link_count(inode);
-                iput(inode);
+                discard_new_inode(inode);
         }
         btrfs_btree_balance_dirty(fs_info);
         return err;
-
-out_fail_inode:
-        unlock_new_inode(inode);
-        goto out_fail;
 }
 
 static noinline int uncompress_inline(struct btrfs_path *path,
@@ -10112,7 +10097,6 @@ static int btrfs_symlink(struct inode *dir, struct dentry *dentry,
         struct btrfs_key key;
         struct inode *inode = NULL;
         int err;
-        int drop_inode = 0;
         u64 objectid;
         u64 index = 0;
         int name_len;
@@ -10145,6 +10129,7 @@ static int btrfs_symlink(struct inode *dir, struct dentry *dentry,
                                 objectid, S_IFLNK|S_IRWXUGO, &index);
         if (IS_ERR(inode)) {
                 err = PTR_ERR(inode);
+                inode = NULL;
                 goto out_unlock;
         }
 
@@ -10161,12 +10146,12 @@ static int btrfs_symlink(struct inode *dir, struct dentry *dentry,
 
         err = btrfs_init_inode_security(trans, inode, dir, &dentry->d_name);
         if (err)
-                goto out_unlock_inode;
+                goto out_unlock;
 
         path = btrfs_alloc_path();
         if (!path) {
                 err = -ENOMEM;
-                goto out_unlock_inode;
+                goto out_unlock;
         }
         key.objectid = btrfs_ino(BTRFS_I(inode));
         key.offset = 0;
@@ -10176,7 +10161,7 @@ static int btrfs_symlink(struct inode *dir, struct dentry *dentry,
                                       datasize);
         if (err) {
                 btrfs_free_path(path);
-                goto out_unlock_inode;
+                goto out_unlock;
         }
         leaf = path->nodes[0];
         ei = btrfs_item_ptr(leaf, path->slots[0],
@@ -10208,26 +10193,19 @@ static int btrfs_symlink(struct inode *dir, struct dentry *dentry,
         if (!err)
                 err = btrfs_add_nondir(trans, BTRFS_I(dir), dentry,
                                 BTRFS_I(inode), 0, index);
-        if (err) {
-                drop_inode = 1;
-                goto out_unlock_inode;
-        }
+        if (err)
+                goto out_unlock;
 
         d_instantiate_new(dentry, inode);
 
 out_unlock:
         btrfs_end_transaction(trans);
-        if (drop_inode) {
+        if (err && inode) {
                 inode_dec_link_count(inode);
-                iput(inode);
+                discard_new_inode(inode);
         }
         btrfs_btree_balance_dirty(fs_info);
         return err;
-
-out_unlock_inode:
-        drop_inode = 1;
-        unlock_new_inode(inode);
-        goto out_unlock;
 }
 
 static int __btrfs_prealloc_file_range(struct inode *inode, int mode,
@@ -10436,14 +10414,14 @@ static int btrfs_tmpfile(struct inode *dir, struct dentry *dentry, umode_t mode)
 
         ret = btrfs_init_inode_security(trans, inode, dir, NULL);
         if (ret)
-                goto out_inode;
+                goto out;
 
         ret = btrfs_update_inode(trans, root, inode);
         if (ret)
-                goto out_inode;
+                goto out;
         ret = btrfs_orphan_add(trans, BTRFS_I(inode));
         if (ret)
-                goto out_inode;
+                goto out;
 
         /*
          * We set number of links to 0 in btrfs_new_inode(), and here we set
@@ -10453,21 +10431,15 @@ static int btrfs_tmpfile(struct inode *dir, struct dentry *dentry, umode_t mode)
          *    d_tmpfile() -> inode_dec_link_count() -> drop_nlink()
          */
         set_nlink(inode, 1);
-        unlock_new_inode(inode);
         d_tmpfile(dentry, inode);
+        unlock_new_inode(inode);
         mark_inode_dirty(inode);
-
 out:
         btrfs_end_transaction(trans);
-        if (ret)
-                iput(inode);
+        if (ret && inode)
+                discard_new_inode(inode);
         btrfs_btree_balance_dirty(fs_info);
         return ret;
-
-out_inode:
-        unlock_new_inode(inode);
-        goto out;
-
 }
 
 __attribute__((const))