samba/CVE-2020-10745-6.patch

56 lines
1.7 KiB
Diff

From 83b00656ea0e8cfdce8a9c1cef71e41477e8e6f0 Mon Sep 17 00:00:00 2001
From: Douglas Bagnall <douglas.bagnall@catalyst.net.nz>
Date: Fri, 15 May 2020 00:06:08 +1200
Subject: [PATCH 17/22] CVE-2020-10745: dns_util/push: forbid names longer than
255 bytes
As per RFC 1035.
BUG: https://bugzilla.samba.org/show_bug.cgi?id=14378
Signed-off-by: Douglas Bagnall <douglas.bagnall@catalyst.net.nz>
---
librpc/ndr/ndr_dns_utils.c | 10 +++++++++-
selftest/knownfail.d/ndr_dns_nbt | 1 -
2 files changed, 9 insertions(+), 2 deletions(-)
diff --git a/librpc/ndr/ndr_dns_utils.c b/librpc/ndr/ndr_dns_utils.c
index 6931dac422d..b7f11dbab4e 100644
--- a/librpc/ndr/ndr_dns_utils.c
+++ b/librpc/ndr/ndr_dns_utils.c
@@ -11,6 +11,8 @@ enum ndr_err_code ndr_push_dns_string_list(struct ndr_push *ndr,
int ndr_flags,
const char *s)
{
+ const char *start = s;
+
if (!(ndr_flags & NDR_SCALARS)) {
return NDR_ERR_SUCCESS;
}
@@ -84,7 +86,13 @@ enum ndr_err_code ndr_push_dns_string_list(struct ndr_push *ndr,
talloc_free(compname);
s += complen;
- if (*s == '.') s++;
+ if (*s == '.') {
+ s++;
+ }
+ if (s - start > 255) {
+ return ndr_push_error(ndr, NDR_ERR_STRING,
+ "name > 255 character long");
+ }
}
/* if we reach the end of the string and have pushed the last component
diff --git a/selftest/knownfail.d/ndr_dns_nbt b/selftest/knownfail.d/ndr_dns_nbt
index e11c121b7a7..603395c8c50 100644
--- a/selftest/knownfail.d/ndr_dns_nbt
+++ b/selftest/knownfail.d/ndr_dns_nbt
@@ -1,3 +1,2 @@
-librpc.ndr.ndr_dns_nbt.test_ndr_dns_string_half_dots
librpc.ndr.ndr_dns_nbt.test_ndr_nbt_string_all_dots
librpc.ndr.ndr_dns_nbt.test_ndr_nbt_string_half_dots
--
2.17.1