From: Paulo Alcantara <pc@manguebit.com>
Date: Wed, 29 Mar 2023 17:14:22 -0300
Subject: [PATCH] cifs: prevent infinite recursion in CIFSGetDFSRefer()
References: bsc#1012628
Patch-mainline: 6.2.10
Git-commit: 09ba47b44d26b475bbdf9c80db9e0193d2b58956

commit 09ba47b44d26b475bbdf9c80db9e0193d2b58956 upstream.

We can't call smb_init() in CIFSGetDFSRefer() as cifs_reconnect_tcon()
may end up calling CIFSGetDFSRefer() again to get new DFS referrals
and thus causing an infinite recursion.

Signed-off-by: Paulo Alcantara (SUSE) <pc@manguebit.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Cc: stable@vger.kernel.org # 6.2
Signed-off-by: Steve French <stfrench@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
---
 fs/cifs/cifssmb.c | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/fs/cifs/cifssmb.c b/fs/cifs/cifssmb.c
index 5ca4a538..f71f8533 100644
--- a/fs/cifs/cifssmb.c
+++ b/fs/cifs/cifssmb.c
@@ -4377,8 +4377,13 @@ CIFSGetDFSRefer(const unsigned int xid, struct cifs_ses *ses,
 		return -ENODEV;
 
 getDFSRetry:
-	rc = smb_init(SMB_COM_TRANSACTION2, 15, ses->tcon_ipc, (void **) &pSMB,
-		      (void **) &pSMBr);
+	/*
+	 * Use smb_init_no_reconnect() instead of smb_init() as
+	 * CIFSGetDFSRefer() may be called from cifs_reconnect_tcon() and thus
+	 * causing an infinite recursion.
+	 */
+	rc = smb_init_no_reconnect(SMB_COM_TRANSACTION2, 15, ses->tcon_ipc,
+				   (void **)&pSMB, (void **)&pSMBr);
 	if (rc)
 		return rc;
 
-- 
2.35.3