From: Paulo Alcantara <pc@manguebit.com>
Date: Wed, 29 Mar 2023 20:14:22 +0000 (-0300)
Subject: cifs: prevent infinite recursion in CIFSGetDFSRefer()
X-Git-Url: https://www.infradead.org/git/?a=commitdiff_plain;h=eb94ea52afff7f0d4dfcb200ba45855fcf7986a3;p=users%2Fjedix%2Flinux-maple.git

cifs: prevent infinite recursion in CIFSGetDFSRefer()

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>
---

diff --git a/fs/cifs/cifssmb.c b/fs/cifs/cifssmb.c
index 4bc6ba87baf4c..c90d4ec9292ca 100644
--- a/fs/cifs/cifssmb.c
+++ b/fs/cifs/cifssmb.c
@@ -4319,8 +4319,13 @@ 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;