cifs: if deferred close is disabled then close files immediately

jira VULN-131073
cve-pre CVE-2025-38527
commit-author Bharath SM <[email protected]>
commit df9d70c

If defer close timeout value is set to 0, then there is no
need to include files in the deferred close list and utilize
the delayed worker for closing. Instead, we can close them
immediately.

	Signed-off-by: Bharath SM <[email protected]>
	Reviewed-by: Shyam Prasad N <[email protected]>
	Cc: [email protected]
	Signed-off-by: Steve French <[email protected]>
(cherry picked from commit df9d70c)
	Signed-off-by: Brett Mastbergen <[email protected]>

Author: bmastbergen

fs/cifs/file.c

@@ -948,8 +948,8 @@ int cifs_close(struct inode *inode, struct file *file)
 		cfile = file->private_data;
 		file->private_data = NULL;
 		dclose = kmalloc(sizeof(struct cifs_deferred_close), GFP_KERNEL);
-		if ((cinode->oplock == CIFS_CACHE_RHW_FLG) &&
-		    cinode->lease_granted &&
+		if ((cifs_sb->ctx->closetimeo && cinode->oplock == CIFS_CACHE_RHW_FLG)
+		    && cinode->lease_granted &&
 		    !test_bit(CIFS_INO_CLOSE_ON_LOCK, &cinode->flags) &&
 		    dclose) {
 			if (test_and_clear_bit(CIFS_INO_MODIFIED_ATTR, &cinode->flags)) {