samba/sme10/CVE-2017-15275.patch

From 6dd87a82a733184df3a6f09e020f6a3c2b365ca2 Mon Sep 17 00:00:00 2001
From: Jeremy Allison <jra@samba.org>
Date: Wed, 20 Sep 2017 11:04:50 -0700
Subject: [PATCH] s3: smbd: Chain code can return uninitialized memory when
 talloc buffer is grown.

Ensure we zero out unused grown area.

CVE-2017-15275

BUG: https://bugzilla.samba.org/show_bug.cgi?id=13077

Signed-off-by: Jeremy Allison <jra@samba.org>
---
 source3/smbd/srvstr.c | 14 ++++++++++++++
 1 file changed, 14 insertions(+)

diff --git a/source3/smbd/srvstr.c b/source3/smbd/srvstr.c
index 56dceba8c6c..c2d70b32c32 100644
--- a/source3/smbd/srvstr.c
+++ b/source3/smbd/srvstr.c
@@ -110,6 +110,20 @@ ssize_t message_push_string(uint8_t **outbuf, const char *str, int flags)
                DEBUG(0, ("srvstr_push failed\n"));
                return -1;
        }
+
+       /*
+        * Ensure we clear out the extra data we have
+        * grown the buffer by, but not written to.
+        */
+       if (buf_size + result < buf_size) {
+               return -1;
+       }
+       if (grow_size < result) {
+               return -1;
+       }
+
+       memset(tmp + buf_size + result, '\0', grow_size - result);
+
        set_message_bcc((char *)tmp, smb_buflen(tmp) + result);
 
        *outbuf = tmp;
-- 
2.14.2.920.gcf0c67979c-goog

1	From 6dd87a82a733184df3a6f09e020f6a3c2b365ca2 Mon Sep 17 00:00:00 2001
2	From: Jeremy Allison <jra@samba.org>
3	Date: Wed, 20 Sep 2017 11:04:50 -0700
4	Subject: [PATCH] s3: smbd: Chain code can return uninitialized memory when
5	talloc buffer is grown.
6
7	Ensure we zero out unused grown area.
8
9	CVE-2017-15275
10
11	BUG: https://bugzilla.samba.org/show_bug.cgi?id=13077
12
13	Signed-off-by: Jeremy Allison <jra@samba.org>
14	---
15	source3/smbd/srvstr.c \| 14 ++++++++++++++
16	1 file changed, 14 insertions(+)
17
18	diff --git a/source3/smbd/srvstr.c b/source3/smbd/srvstr.c
19	index 56dceba8c6c..c2d70b32c32 100644
20	--- a/source3/smbd/srvstr.c
21	+++ b/source3/smbd/srvstr.c
22	@@ -110,6 +110,20 @@ ssize_t message_push_string(uint8_t *outbuf, const char str, int flags)
23	DEBUG(0, ("srvstr_push failed\n"));
24	return -1;
25	}
26	+
27	+ /*
28	+ * Ensure we clear out the extra data we have
29	+ * grown the buffer by, but not written to.
30	+ */
31	+ if (buf_size + result < buf_size) {
32	+ return -1;
33	+ }
34	+ if (grow_size < result) {
35	+ return -1;
36	+ }
37	+
38	+ memset(tmp + buf_size + result, '\0', grow_size - result);
39	+
40	set_message_bcc((char *)tmp, smb_buflen(tmp) + result);
41
42	*outbuf = tmp;
43	--
44	2.14.2.920.gcf0c67979c-goog
45