[PATCH 03/16] vfs: don't evict uninitialized inode

From: Al Viro
Date: Sun Jul 29 2018 - 18:06:09 EST


From: Miklos Szeredi <mszeredi@xxxxxxxxxx>

iput() ends up calling ->evict() on new inode, which is not yet initialized
by owning fs. So use destroy_inode() instead.

Add to sb->s_inodes list only if inode is not in I_CREATING state (meaning
that it wasn't allocated with new_inode(), which already does the
insertion).

Reported-by: Al Viro <viro@xxxxxxxxxxxxxxxxxx>
Signed-off-by: Miklos Szeredi <mszeredi@xxxxxxxxxx>
Fixes: 80ea09a002bf ("vfs: factor out inode_insert5()")
Signed-off-by: Al Viro <viro@xxxxxxxxxxxxxxxxxx>
---
fs/inode.c | 8 ++++++--
1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/fs/inode.c b/fs/inode.c
index 04dd7e0d5142..0aa5b29b6f87 100644
--- a/fs/inode.c
+++ b/fs/inode.c
@@ -1050,6 +1050,7 @@ struct inode *inode_insert5(struct inode *inode, unsigned long hashval,
{
struct hlist_head *head = inode_hashtable + hash(inode->i_sb, hashval);
struct inode *old;
+ bool creating = inode->i_state & I_CREATING;

again:
spin_lock(&inode_hash_lock);
@@ -1083,6 +1084,8 @@ struct inode *inode_insert5(struct inode *inode, unsigned long hashval,
inode->i_state |= I_NEW;
hlist_add_head(&inode->i_hash, head);
spin_unlock(&inode->i_lock);
+ if (!creating)
+ inode_sb_list_add(inode);
unlock:
spin_unlock(&inode_hash_lock);

@@ -1117,12 +1120,13 @@ struct inode *iget5_locked(struct super_block *sb, unsigned long hashval,
struct inode *inode = ilookup5(sb, hashval, test, data);

if (!inode) {
- struct inode *new = new_inode(sb);
+ struct inode *new = alloc_inode(sb);

if (new) {
+ new->i_state = 0;
inode = inode_insert5(new, hashval, test, set, data);
if (unlikely(inode != new))
- iput(new);
+ destroy_inode(new);
}
}
return inode;
--
2.11.0