All dentries in a case-insensitive filesystem have the same set of
dentry operations. Therefore, we should let VFS propagate them from
sb->s_d_op d_alloc instead of setting at lookup time.
This was already the case before commit bb9cd9106b22 ("fscrypt: Have
filesystems handle their d_ops"), but it was changed to set at
lookup-time to facilitate the integration with fscrypt. But it's a
problem because dentries that don't get created through ->lookup() won't
have any visibility of the operations. Let's revert to the previous
implementation.
Suggested-by: Al Viro <viro@xxxxxxxxxxxxxxxxxx>
Signed-off-by: Gabriel Krisman Bertazi <krisman@xxxxxxx>
---
changes since v1:
- Fix CONFIG_UNICODE=n build (lkp)
---
fs/ext4/namei.c | 6 +++++-
fs/ext4/super.c | 5 +++++
2 files changed, 10 insertions(+), 1 deletion(-)
diff --git a/fs/ext4/namei.c b/fs/ext4/namei.c
index d252935f9c8a..463e73fb5bf0 100644
--- a/fs/ext4/namei.c
+++ b/fs/ext4/namei.c
@@ -1762,7 +1762,11 @@ static struct buffer_head *ext4_lookup_entry(struct inode *dir,
struct buffer_head *bh;
err = ext4_fname_prepare_lookup(dir, dentry, &fname);
- generic_set_encrypted_ci_d_ops(dentry);
+
+ /* Case-insensitive volumes set dentry ops through sb->s_d_op. */
+ if (!dir->i_sb->s_d_op)
+ generic_set_encrypted_ci_d_ops(dentry);
+
if (err == -ENOENT)
return NULL;
if (err)
diff --git a/fs/ext4/super.c b/fs/ext4/super.c
index c5fcf377ab1f..e0680d0641aa 100644
--- a/fs/ext4/super.c
+++ b/fs/ext4/super.c
@@ -5493,6 +5493,11 @@ static int __ext4_fill_super(struct fs_context *fc, struct super_block *sb)
goto failed_mount4;
}
+#if IS_ENABLED(CONFIG_UNICODE)
+ if (sb->s_encoding)
+ sb->s_d_op = &generic_ci_dentry_ops;
+#endif
+
sb->s_root = d_make_root(root);
if (!sb->s_root) {
ext4_msg(sb, KERN_ERR, "get root dentry failed");
--
2.43.0
