From: Ronnie Sahlberg <lsahlber@redhat.com>
Date: Tue, 9 Mar 2021 09:07:30 +1000
Subject: [PATCH] cifs: store a pointer to the root dentry in cifs_sb_info once
we have completed mounting the share
Git-commit: 269f67e1ffead61777b1b0cf2ea0f61d06f8c56d
Patch-mainline: v5.13-rc1
References: bsc#1192606
And use this to only allow to take out a shared handle once the mount has completed and the
sb becomes available.
This will become important in follow up patches where we will start holding a reference to the
directory dentry for the shared handle during the lifetime of the handle.
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Acked-by: Enzo Matsumiya <ematsumiya@suse.de>
---
fs/cifs/cifs_fs_sb.h | 4 ++++
fs/cifs/cifsfs.c | 9 +++++++++
fs/cifs/smb2ops.c | 5 ++++-
3 files changed, 17 insertions(+), 1 deletion(-)
diff --git a/fs/cifs/cifs_fs_sb.h b/fs/cifs/cifs_fs_sb.h
index aa77edc12212..2a5325a7ae49 100644
--- a/fs/cifs/cifs_fs_sb.h
+++ b/fs/cifs/cifs_fs_sb.h
@@ -81,5 +81,9 @@ struct cifs_sb_info {
* (cifs_autodisable_serverino) in order to match new mounts.
*/
bool mnt_cifs_serverino_autodisabled;
+ /*
+ * Available once the mount has completed.
+ */
+ struct dentry *root;
};
#endif /* _CIFS_FS_SB_H */
diff --git a/fs/cifs/cifsfs.c b/fs/cifs/cifsfs.c
index 8dc2306c9092..cf8eceb1d5a5 100644
--- a/fs/cifs/cifsfs.c
+++ b/fs/cifs/cifsfs.c
@@ -257,6 +257,12 @@ cifs_read_super(struct super_block *sb)
static void cifs_kill_sb(struct super_block *sb)
{
struct cifs_sb_info *cifs_sb = CIFS_SB(sb);
+
+ if (cifs_sb->root) {
+ dput(cifs_sb->root);
+ cifs_sb->root = NULL;
+ }
+
kill_anon_super(sb);
cifs_umount(cifs_sb);
}
@@ -886,6 +892,9 @@ cifs_smb3_do_mount(struct file_system_type *fs_type,
if (IS_ERR(root))
goto out_super;
+ if (cifs_sb)
+ cifs_sb->root = dget(root);
+
cifs_dbg(FYI, "dentry root is: %p\n", root);
return root;
diff --git a/fs/cifs/smb2ops.c b/fs/cifs/smb2ops.c
index 89269a5c02c7..3ff460035705 100644
--- a/fs/cifs/smb2ops.c
+++ b/fs/cifs/smb2ops.c
@@ -751,8 +751,11 @@ int open_cached_dir(unsigned int xid, struct cifs_tcon *tcon,
if (tcon->nohandlecache)
return -ENOTSUPP;
+ if (cifs_sb->root == NULL)
+ return -ENOENT;
+
if (strlen(path))
- return -ENOTSUPP;
+ return -ENOENT;
mutex_lock(&tcon->crfid.fid_mutex);
if (tcon->crfid.is_valid) {
--
2.33.1