From: Ronnie Sahlberg <lsahlber@redhat.com>
Date: Tue, 31 May 2022 03:01:17 +0000 (+1000)
Subject: cifs: fix potential double free during failed mount
X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=ce0008a0e410cdd95f0d8cd81b2902ec10a660c4;p=linux.git

cifs: fix potential double free during failed mount

commit 8378a51e3f8140f60901fb27208cc7a6e47047b5 upstream.

RHBZ: https://bugzilla.redhat.com/show_bug.cgi?id=2088799

Cc: stable@vger.kernel.org
Signed-off-by: Roberto Bergantinos <rbergant@redhat.com>
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---

diff --git a/fs/cifs/cifsfs.c b/fs/cifs/cifsfs.c
index 8f8d281e31510..1e4f5ee9768ab 100644
--- a/fs/cifs/cifsfs.c
+++ b/fs/cifs/cifsfs.c
@@ -826,7 +826,7 @@ cifs_smb3_do_mount(struct file_system_type *fs_type,
 	      int flags, struct smb3_fs_context *old_ctx)
 {
 	int rc;
-	struct super_block *sb;
+	struct super_block *sb = NULL;
 	struct cifs_sb_info *cifs_sb = NULL;
 	struct cifs_mnt_data mnt_data;
 	struct dentry *root;
@@ -922,9 +922,11 @@ out_super:
 	return root;
 out:
 	if (cifs_sb) {
-		kfree(cifs_sb->prepath);
-		smb3_cleanup_fs_context(cifs_sb->ctx);
-		kfree(cifs_sb);
+		if (!sb || IS_ERR(sb)) {  /* otherwise kill_sb will handle */
+			kfree(cifs_sb->prepath);
+			smb3_cleanup_fs_context(cifs_sb->ctx);
+			kfree(cifs_sb);
+		}
 	}
 	return root;
 }