fs/cifs: make share unaccessible at root level mountable
if, when mounting //HOST/share/sub/dir/foo we can query /sub/dir/foo but
not any of the path components above:
- store the /sub/dir/foo prefix in the cifs super_block info
- in the superblock, set root dentry to the subpath dentry (instead of
the share root)
- set a flag in the superblock to remember it
- use prefixpath when building path from a dentry
fixes bso#8950
Signed-off-by: Aurelien Aptel <aaptel@suse.com>
CC: Stable <stable@vger.kernel.org>
Reviewed-by: Pavel Shilovsky <pshilovsky@samba.org>
Signed-off-by: Steve French <smfrench@gmail.com>
diff --git a/fs/cifs/inode.c b/fs/cifs/inode.c
index 514dadb..b87efd0 100644
--- a/fs/cifs/inode.c
+++ b/fs/cifs/inode.c
@@ -1002,10 +1002,26 @@
struct inode *inode = NULL;
long rc;
struct cifs_tcon *tcon = cifs_sb_master_tcon(cifs_sb);
+ char *path = NULL;
+ int len;
+
+ if ((cifs_sb->mnt_cifs_flags & CIFS_MOUNT_USE_PREFIX_PATH)
+ && cifs_sb->prepath) {
+ len = strlen(cifs_sb->prepath);
+ path = kzalloc(len + 2 /* leading sep + null */, GFP_KERNEL);
+ if (path == NULL)
+ return ERR_PTR(-ENOMEM);
+ path[0] = '/';
+ memcpy(path+1, cifs_sb->prepath, len);
+ } else {
+ path = kstrdup("", GFP_KERNEL);
+ if (path == NULL)
+ return ERR_PTR(-ENOMEM);
+ }
xid = get_xid();
if (tcon->unix_ext) {
- rc = cifs_get_inode_info_unix(&inode, "", sb, xid);
+ rc = cifs_get_inode_info_unix(&inode, path, sb, xid);
/* some servers mistakenly claim POSIX support */
if (rc != -EOPNOTSUPP)
goto iget_no_retry;
@@ -1013,7 +1029,8 @@
tcon->unix_ext = false;
}
- rc = cifs_get_inode_info(&inode, "", NULL, sb, xid, NULL);
+ convert_delimiter(path, CIFS_DIR_SEP(cifs_sb));
+ rc = cifs_get_inode_info(&inode, path, NULL, sb, xid, NULL);
iget_no_retry:
if (!inode) {
@@ -1042,6 +1059,7 @@
}
out:
+ kfree(path);
/* can not call macro free_xid here since in a void func
* TODO: This is no longer true
*/