cifs: Check if server supports reparse points before using them

Do not attempt to query or create reparse point when server fs does not
support it. This will prevent creating unusable empty object on the server.

Signed-off-by: Pali Rohár <pali@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>

diff --git a/fs/smb/client/cifssmb.c b/fs/smb/client/cifssmb.c
index 4fc9485c5d91a3481c1c67cfd9d7f3763d3b52eb..364ab7573b360223862c8ced91e923917d5a37ed 100644 (file)
--- a/fs/smb/client/cifssmb.c
+++ b/fs/smb/client/cifssmb.c
@@ -2709,6 +2709,9 @@ int cifs_query_reparse_point(const unsigned int xid,
        if (cap_unix(tcon->ses))
                return -EOPNOTSUPP;
 
+       if (!(le32_to_cpu(tcon->fsAttrInfo.Attributes) & FILE_SUPPORTS_REPARSE_POINTS))
+               return -EOPNOTSUPP;
+
        oparms = (struct cifs_open_parms) {
                .tcon = tcon,
                .cifs_sb = cifs_sb,

diff --git a/fs/smb/client/link.c b/fs/smb/client/link.c
index 6e6c09cc5ce7abad829282923730c114de212cd7..a88253668286035676a17e876d2908b7d7c6d10d 100644 (file)
--- a/fs/smb/client/link.c
+++ b/fs/smb/client/link.c
@@ -643,7 +643,8 @@ cifs_symlink(struct mnt_idmap *idmap, struct inode *inode,
        case CIFS_SYMLINK_TYPE_NATIVE:
        case CIFS_SYMLINK_TYPE_NFS:
        case CIFS_SYMLINK_TYPE_WSL:
-               if (server->ops->create_reparse_symlink) {
+               if (server->ops->create_reparse_symlink &&
+                   (le32_to_cpu(pTcon->fsAttrInfo.Attributes) & FILE_SUPPORTS_REPARSE_POINTS)) {
                        rc = server->ops->create_reparse_symlink(xid, inode,
                                                                 direntry,
                                                                 pTcon,

diff --git a/fs/smb/client/smb2inode.c b/fs/smb/client/smb2inode.c
index 826b57a5a2a8d2afb8e5d9b8351248ee855937a1..e9fd3e204a6f4081e9d3b99a1de19e21b2fd3f6c 100644 (file)
--- a/fs/smb/client/smb2inode.c
+++ b/fs/smb/client/smb2inode.c
@@ -1273,6 +1273,14 @@ struct inode *smb2_get_reparse_inode(struct cifs_open_info_data *data,
        int rc;
        int i;
 
+       /*
+        * If server filesystem does not support reparse points then do not
+        * attempt to create reparse point. This will prevent creating unusable
+        * empty object on the server.
+        */
+       if (!(le32_to_cpu(tcon->fsAttrInfo.Attributes) & FILE_SUPPORTS_REPARSE_POINTS))
+               return ERR_PTR(-EOPNOTSUPP);
+
        oparms = CIFS_OPARMS(cifs_sb, tcon, full_path,
                             SYNCHRONIZE | DELETE |
                             FILE_READ_ATTRIBUTES |

diff --git a/fs/smb/client/smb2ops.c b/fs/smb/client/smb2ops.c
index 6958825431af25e5a646cbebcc367994144829e2..a700e592196149ab92a43bb4e3c9dd3f2284c04c 100644 (file)
--- a/fs/smb/client/smb2ops.c
+++ b/fs/smb/client/smb2ops.c
@@ -5229,7 +5229,7 @@ static int smb2_make_node(unsigned int xid, struct inode *inode,
                          const char *full_path, umode_t mode, dev_t dev)
 {
        struct cifs_sb_info *cifs_sb = CIFS_SB(inode->i_sb);
-       int rc;
+       int rc = -EOPNOTSUPP;
 
        /*
         * Check if mounted with mount parm 'sfu' mount parm.
@@ -5240,7 +5240,7 @@ static int smb2_make_node(unsigned int xid, struct inode *inode,
        if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_UNX_EMUL) {
                rc = cifs_sfu_make_node(xid, inode, dentry, tcon,
                                        full_path, mode, dev);
-       } else {
+       } else if (le32_to_cpu(tcon->fsAttrInfo.Attributes) & FILE_SUPPORTS_REPARSE_POINTS) {
                rc = smb2_mknod_reparse(xid, inode, dentry, tcon,
                                        full_path, mode, dev);
        }