Update Linux to v5.4.2
Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/net/dns_resolver/Kconfig b/net/dns_resolver/Kconfig
index 50d49f7..0a1c223 100644
--- a/net/dns_resolver/Kconfig
+++ b/net/dns_resolver/Kconfig
@@ -1,3 +1,4 @@
+# SPDX-License-Identifier: GPL-2.0-only
#
# Configuration for DNS Resolver
#
diff --git a/net/dns_resolver/Makefile b/net/dns_resolver/Makefile
index d5c13c2..877532d 100644
--- a/net/dns_resolver/Makefile
+++ b/net/dns_resolver/Makefile
@@ -1,3 +1,4 @@
+# SPDX-License-Identifier: GPL-2.0-only
#
# Makefile for the Linux DNS Resolver.
#
diff --git a/net/dns_resolver/dns_key.c b/net/dns_resolver/dns_key.c
index 7f45348..3e1a906 100644
--- a/net/dns_resolver/dns_key.c
+++ b/net/dns_resolver/dns_key.c
@@ -29,6 +29,7 @@
#include <linux/keyctl.h>
#include <linux/err.h>
#include <linux/seq_file.h>
+#include <linux/dns_resolver.h>
#include <keys/dns_resolver-type.h>
#include <keys/user-type.h>
#include "internal.h"
@@ -48,27 +49,86 @@
/*
* Preparse instantiation data for a dns_resolver key.
*
- * The data must be a NUL-terminated string, with the NUL char accounted in
- * datalen.
+ * For normal hostname lookups, the data must be a NUL-terminated string, with
+ * the NUL char accounted in datalen.
*
* If the data contains a '#' characters, then we take the clause after each
* one to be an option of the form 'key=value'. The actual data of interest is
* the string leading up to the first '#'. For instance:
*
* "ip1,ip2,...#foo=bar"
+ *
+ * For server list requests, the data must begin with a NUL char and be
+ * followed by a byte indicating the version of the data format. Version 1
+ * looks something like (note this is packed):
+ *
+ * u8 Non-string marker (ie. 0)
+ * u8 Content (DNS_PAYLOAD_IS_*)
+ * u8 Version (e.g. 1)
+ * u8 Source of server list
+ * u8 Lookup status of server list
+ * u8 Number of servers
+ * foreach-server {
+ * __le16 Name length
+ * __le16 Priority (as per SRV record, low first)
+ * __le16 Weight (as per SRV record, higher first)
+ * __le16 Port
+ * u8 Source of address list
+ * u8 Lookup status of address list
+ * u8 Protocol (DNS_SERVER_PROTOCOL_*)
+ * u8 Number of addresses
+ * char[] Name (not NUL-terminated)
+ * foreach-address {
+ * u8 Family (DNS_ADDRESS_IS_*)
+ * union {
+ * u8[4] ipv4_addr
+ * u8[16] ipv6_addr
+ * }
+ * }
+ * }
+ *
*/
static int
dns_resolver_preparse(struct key_preparsed_payload *prep)
{
+ const struct dns_payload_header *bin;
struct user_key_payload *upayload;
unsigned long derrno;
int ret;
int datalen = prep->datalen, result_len = 0;
const char *data = prep->data, *end, *opt;
+ if (datalen <= 1 || !data)
+ return -EINVAL;
+
+ if (data[0] == 0) {
+ /* It may be a server list. */
+ if (datalen <= sizeof(*bin))
+ return -EINVAL;
+
+ bin = (const struct dns_payload_header *)data;
+ kenter("[%u,%u],%u", bin->content, bin->version, datalen);
+ if (bin->content != DNS_PAYLOAD_IS_SERVER_LIST) {
+ pr_warn_ratelimited(
+ "dns_resolver: Unsupported content type (%u)\n",
+ bin->content);
+ return -EINVAL;
+ }
+
+ if (bin->version != 1) {
+ pr_warn_ratelimited(
+ "dns_resolver: Unsupported server list version (%u)\n",
+ bin->version);
+ return -EINVAL;
+ }
+
+ result_len = datalen;
+ goto store_result;
+ }
+
kenter("'%*.*s',%u", datalen, datalen, data, datalen);
- if (datalen <= 1 || !data || data[datalen - 1] != '\0')
+ if (!data || data[datalen - 1] != '\0')
return -EINVAL;
datalen--;
@@ -144,6 +204,7 @@
return 0;
}
+store_result:
kdebug("store result");
prep->quotalen = result_len;
@@ -253,6 +314,7 @@
struct key_type key_type_dns_resolver = {
.name = "dns_resolver",
+ .flags = KEY_TYPE_NET_DOMAIN,
.preparse = dns_resolver_preparse,
.free_preparse = dns_resolver_free_preparse,
.instantiate = generic_key_instantiate,
diff --git a/net/dns_resolver/dns_query.c b/net/dns_resolver/dns_query.c
index 49da670..cab4e0d 100644
--- a/net/dns_resolver/dns_query.c
+++ b/net/dns_resolver/dns_query.c
@@ -40,6 +40,7 @@
#include <linux/cred.h>
#include <linux/dns_resolver.h>
#include <linux/err.h>
+#include <net/net_namespace.h>
#include <keys/dns_resolver-type.h>
#include <keys/user-type.h>
@@ -48,12 +49,14 @@
/**
* dns_query - Query the DNS
+ * @net: The network namespace to operate in.
* @type: Query type (or NULL for straight host->IP lookup)
* @name: Name to look up
* @namelen: Length of name
* @options: Request options (or NULL if no options)
* @_result: Where to place the returned data (or NULL)
* @_expiry: Where to store the result expiry time (or NULL)
+ * @invalidate: Always invalidate the key after use
*
* The data will be returned in the pointer at *result, if provided, and the
* caller is responsible for freeing it.
@@ -68,8 +71,10 @@
*
* Returns the size of the result on success, -ve error code otherwise.
*/
-int dns_query(const char *type, const char *name, size_t namelen,
- const char *options, char **_result, time64_t *_expiry)
+int dns_query(struct net *net,
+ const char *type, const char *name, size_t namelen,
+ const char *options, char **_result, time64_t *_expiry,
+ bool invalidate)
{
struct key *rkey;
struct user_key_payload *upayload;
@@ -94,8 +99,6 @@
desclen += typelen + 1;
}
- if (!namelen)
- namelen = strnlen(name, 256);
if (namelen < 3 || namelen > 255)
return -EINVAL;
desclen += namelen + 1;
@@ -122,7 +125,7 @@
* add_key() to preinstall malicious redirections
*/
saved_cred = override_creds(dns_resolver_cache);
- rkey = request_key(&key_type_dns_resolver, desc, options);
+ rkey = request_key_net(&key_type_dns_resolver, desc, net, options);
revert_creds(saved_cred);
kfree(desc);
if (IS_ERR(rkey)) {
@@ -148,12 +151,9 @@
if (_result) {
ret = -ENOMEM;
- *_result = kmalloc(len + 1, GFP_KERNEL);
+ *_result = kmemdup_nul(upayload->data, len, GFP_KERNEL);
if (!*_result)
goto put;
-
- memcpy(*_result, upayload->data, len);
- (*_result)[len] = '\0';
}
if (_expiry)
@@ -162,6 +162,8 @@
ret = len;
put:
up_read(&rkey->sem);
+ if (invalidate)
+ key_invalidate(rkey);
key_put(rkey);
out:
kleave(" = %d", ret);