Commit 6c06be90 authored Oct 19, 2024 by Pali Rohár Committed by Steve French Mar 26, 2025

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>

parent 5eeebd99

fs/smb/client/cifssmb.c

+3 −0

Original line number	Diff line number	Diff line
		@@ -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,

fs/smb/client/link.c

+2 −1

Original line number	Diff line number	Diff line
		@@ -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,

fs/smb/client/smb2inode.c

+8 −0

Original line number	Diff line number	Diff line
		@@ -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 \|

fs/smb/client/smb2ops.c

+2 −2

Original line number	Diff line number	Diff line
		@@ -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);
		}