1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
|
From ccf53dfdcd39f3526dbc2f20e1245674155380ff Mon Sep 17 00:00:00 2001
From: Zheng Ruoqin <zhengrq.fnst@cn.fujitsu.com>
Date: Fri, 11 Dec 2020 11:32:44 +0900
Subject: [PATCH] s4: torture: Add smb2.notify.handle-permissions test.
s3: smbd: Ensure change notifies can't get set unless the
directory handle is open for SEC_DIR_LIST.
CVE-2020-14318
BUG: https://bugzilla.samba.org/show_bug.cgi?id=14434
Signed-off-by: Jeremy Allison <jra@samba.org>
Signed-off-by: Zheng Ruoqin <zhengrq.fnst@cn.fujitsu.com>
---
source3/smbd/notify.c | 8 ++++
source4/torture/smb2/notify.c | 82 ++++++++++++++++++++++++++++++++++-
2 files changed, 89 insertions(+), 1 deletion(-)
diff --git a/source3/smbd/notify.c b/source3/smbd/notify.c
index 44c0b09..d23c03b 100644
--- a/source3/smbd/notify.c
+++ b/source3/smbd/notify.c
@@ -283,6 +283,14 @@ NTSTATUS change_notify_create(struct files_struct *fsp, uint32_t filter,
char fullpath[len+1];
NTSTATUS status = NT_STATUS_NOT_IMPLEMENTED;
+ /*
+ * Setting a changenotify needs READ/LIST access
+ * on the directory handle.
+ */
+ if (!(fsp->access_mask & SEC_DIR_LIST)) {
+ return NT_STATUS_ACCESS_DENIED;
+ }
+
if (fsp->notify != NULL) {
DEBUG(1, ("change_notify_create: fsp->notify != NULL, "
"fname = %s\n", fsp->fsp_name->base_name));
diff --git a/source4/torture/smb2/notify.c b/source4/torture/smb2/notify.c
index ebb4f8a..a5c9b94 100644
--- a/source4/torture/smb2/notify.c
+++ b/source4/torture/smb2/notify.c
@@ -2569,6 +2569,83 @@ done:
return ok;
}
+/*
+ Test asking for a change notify on a handle without permissions.
+*/
+
+#define BASEDIR_HPERM BASEDIR "_HPERM"
+
+static bool torture_smb2_notify_handle_permissions(
+ struct torture_context *torture,
+ struct smb2_tree *tree)
+{
+ bool ret = true;
+ NTSTATUS status;
+ union smb_notify notify;
+ union smb_open io;
+ struct smb2_handle h1 = {{0}};
+ struct smb2_request *req;
+
+ smb2_deltree(tree, BASEDIR_HPERM);
+ smb2_util_rmdir(tree, BASEDIR_HPERM);
+
+ torture_comment(torture,
+ "TESTING CHANGE NOTIFY "
+ "ON A HANDLE WITHOUT PERMISSIONS\n");
+
+ /*
+ get a handle on the directory
+ */
+ ZERO_STRUCT(io.smb2);
+ io.generic.level = RAW_OPEN_SMB2;
+ io.smb2.in.create_flags = 0;
+ io.smb2.in.desired_access = SEC_FILE_READ_ATTRIBUTE;
+ io.smb2.in.create_options = NTCREATEX_OPTIONS_DIRECTORY;
+ io.smb2.in.file_attributes = FILE_ATTRIBUTE_NORMAL;
+ io.smb2.in.share_access = NTCREATEX_SHARE_ACCESS_READ |
+ NTCREATEX_SHARE_ACCESS_WRITE;
+ io.smb2.in.alloc_size = 0;
+ io.smb2.in.create_disposition = NTCREATEX_DISP_CREATE;
+ io.smb2.in.impersonation_level = SMB2_IMPERSONATION_ANONYMOUS;
+ io.smb2.in.security_flags = 0;
+ io.smb2.in.fname = BASEDIR_HPERM;
+
+ status = smb2_create(tree, torture, &io.smb2);
+ CHECK_STATUS(status, NT_STATUS_OK);
+ h1 = io.smb2.out.file.handle;
+
+ /* ask for a change notify,
+ on file or directory name changes */
+ ZERO_STRUCT(notify.smb2);
+ notify.smb2.level = RAW_NOTIFY_SMB2;
+ notify.smb2.in.buffer_size = 1000;
+ notify.smb2.in.completion_filter = FILE_NOTIFY_CHANGE_NAME;
+ notify.smb2.in.file.handle = h1;
+ notify.smb2.in.recursive = true;
+
+ req = smb2_notify_send(tree, ¬ify.smb2);
+ torture_assert_goto(torture,
+ req != NULL,
+ ret,
+ done,
+ "smb2_notify_send failed\n");
+
+ /*
+ * Cancel it, we don't really want to wait.
+ */
+ smb2_cancel(req);
+ status = smb2_notify_recv(req, torture, ¬ify.smb2);
+ /* Handle h1 doesn't have permissions for ChangeNotify. */
+ CHECK_STATUS(status, NT_STATUS_ACCESS_DENIED);
+
+done:
+ if (!smb2_util_handle_empty(h1)) {
+ smb2_util_close(tree, h1);
+ }
+ smb2_deltree(tree, BASEDIR_HPERM);
+ return ret;
+}
+
/*
basic testing of SMB2 change notify
*/
@@ -2602,7 +2679,10 @@ struct torture_suite *torture_smb2_notify_init(TALLOC_CTX *ctx)
torture_smb2_notify_rmdir3);
torture_suite_add_2smb2_test(suite, "rmdir4",
torture_smb2_notify_rmdir4);
-
+ torture_suite_add_1smb2_test(suite,
+ "handle-permissions",
+ torture_smb2_notify_handle_permissions);
+
suite->description = talloc_strdup(suite, "SMB2-NOTIFY tests");
return suite;
--
2.25.1
|
