Observed issue
==============
For the following scenario:
lttng-relayd: 64 bit
lttng-sessiond: 64 bit
lttng-consumerd: 32 bit
application: 32 bit
Commands
lttng create --set-url=net://127.0.0.1
lttng enable-event -u -a
lttng start
./application
On application start the lttng-relayd reports this error:
DEBUG1 - 14:16:38.
216442600 [
2004731/
2004735]: Done receiving control command payload: fd = 19, payload size = 4376 bytes (in relay_process_control_receive_payload() at main.c:3456)
DEBUG3 - 14:16:38.
216469462 [
2004731/
2004735]: Processing "RELAYD_ADD_STREAM" command for socket 19 (in relay_process_control_command() at main.c:3327)
Error: Unexpected payload size in "cmd_recv_stream_2_11": expected >=
3519925694 bytes, got 4376 bytes
Cause
=====
In `relayd_add_stream`, instead of taking the > 2.11 protocol path, the
`relayd_add_stream_2_2` function is called.
The value of the rsock version number are:
major: 21845
minor: 2
Which is simply invalid since we know that the version should be 2.12.
The relayd sock version numbers are set during the
LTTNG_CONSUMER_ADD_RELAYD_SOCKET command between the lttng-sessiond and
the lttng-consumerd process. It is important to note here that both
processes do NOT have the same bitness.
The serialization and deserialization of `struct lttcomm_relayd_sock` is
the culprit.
`struct lttcomm_relayd_sock` contains a `struct lttcomm_sock`:
struct lttcomm_sock {
int32_t fd;
enum lttcomm_sock_proto proto;
struct lttcomm_sockaddr sockaddr;
const struct lttcomm_proto_ops *ops;
} LTTNG_PACKED;
Note that `ops` is a pointer and its size varies based on the bitness of
the application. Hence the size of the `struct lttcomm_sock` differs
across bitness. Since it is the first member of `struct
lttcomm_relayd_sock`, the memory layout is simply invalid across
bitness (amd64/x86).
This results in invalid parsing for the overall "struct
lttcomm_relayd_sock" when dealing with a lttng-consumerd with a
different bitness than the lttng-sessiond. As far as I know local
tracing scenarios are not affected since this is only relevant when
dealing with a lttng-relayd.
Solution
========
Pass the socket protocol type, relayd major, relayd minor in
`lttcomm_consumer_msg`. On the receiver side, query the network stack to
get the peer information to populate a basic `lttcomm_sock`. Leaving
this work to the OS saves us from having to serialize the `sockaddr_in*`
structs.
Known drawbacks
=========
We rely on `getpeername` for the first time. Compatibility might be a
problem.
This code path assumes a lot of thing that cannot be asserted against
such as the fact that the socket from which we fetch the info must be
`connected`. Still at this point, the socket is completely setup and the
rest of the code depends on it already.
From GETPEERNAME(2):
```
For stream sockets, once a connect(2) has been performed, either
socket can call getpeername() to obtain the address of the peer
socket. On the other hand, datagram sockets are connectionless.
Calling connect(2) on a datagram socket merely sets the peer
address for outgoing datagrams sent with write(2) or recv(2).
The caller of connect(2) can use getpeername() to obtain the
peer address that it earlier set for the socket. However, the
peer socket is unaware of this information, and calling
getpeername() on the peer socket will return no useful
information (unless a connect(2) call was also executed on the
peer). Note also that the receiver of a datagram can obtain the
address of the sender when using recvfrom(2).
```
But here we are always "the caller of connect".
Signed-off-by: Jonathan Rajotte <jonathan.rajotte-julien@efficios.com>
Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>
Change-Id: Ic157c4137b2f20e394c907136687fcbd126f90a0
msg.u.relayd_sock.net_index = consumer->net_seq_index;
msg.u.relayd_sock.type = type;
msg.u.relayd_sock.session_id = session_id;
- memcpy(&msg.u.relayd_sock.sock, rsock, sizeof(msg.u.relayd_sock.sock));
+ msg.u.relayd_sock.major = rsock->major;
+ msg.u.relayd_sock.minor = rsock->minor;
+ msg.u.relayd_sock.relayd_socket_protocol = rsock->sock.proto;
DBG3("Sending relayd sock info to consumer on %d", *consumer_sock->fd_ptr);
ret = consumer_send_msg(consumer_sock, &msg);
*/
#include "common/index/ctf-index.h"
+#include <stdint.h>
#define _LGPL_SOURCE
#include <poll.h>
#include <pthread.h>
* This will create a relayd socket pair and add it to the relayd hash table.
* The caller MUST acquire a RCU read side lock before calling it.
*/
- void consumer_add_relayd_socket(uint64_t net_seq_idx, int sock_type,
- struct lttng_consumer_local_data *ctx, int sock,
+void consumer_add_relayd_socket(uint64_t net_seq_idx,
+ int sock_type,
+ struct lttng_consumer_local_data *ctx,
+ int sock,
struct pollfd *consumer_sockpoll,
- struct lttcomm_relayd_sock *relayd_sock, uint64_t sessiond_id,
- uint64_t relayd_session_id)
+ uint64_t sessiond_id,
+ uint64_t relayd_session_id,
+ uint32_t relayd_version_major,
+ uint32_t relayd_version_minor,
+ enum lttcomm_sock_proto relayd_socket_protocol)
{
int fd = -1, ret = -1, relayd_created = 0;
enum lttcomm_return_code ret_code = LTTCOMM_CONSUMERD_SUCCESS;
struct consumer_relayd_sock_pair *relayd = NULL;
LTTNG_ASSERT(ctx);
- LTTNG_ASSERT(relayd_sock);
+ LTTNG_ASSERT(sock >= 0);
ASSERT_RCU_READ_LOCKED();
DBG("Consumer adding relayd socket (idx: %" PRIu64 ")", net_seq_idx);
switch (sock_type) {
case LTTNG_STREAM_CONTROL:
/* Copy received lttcomm socket */
- lttcomm_copy_sock(&relayd->control_sock.sock, &relayd_sock->sock);
- ret = lttcomm_create_sock(&relayd->control_sock.sock);
- /* Handle create_sock error. */
- if (ret < 0) {
- ret_code = LTTCOMM_CONSUMERD_ENOMEM;
- goto error;
- }
- /*
- * Close the socket created internally by
- * lttcomm_create_sock, so we can replace it by the one
- * received from sessiond.
- */
- if (close(relayd->control_sock.sock.fd)) {
- PERROR("close");
- }
+ ret = lttcomm_populate_sock_from_open_socket(
+ &relayd->control_sock.sock, fd,
+ relayd_socket_protocol);
- /* Assign new file descriptor */
- relayd->control_sock.sock.fd = fd;
/* Assign version values. */
- relayd->control_sock.major = relayd_sock->major;
- relayd->control_sock.minor = relayd_sock->minor;
+ relayd->control_sock.major = relayd_version_major;
+ relayd->control_sock.minor = relayd_version_minor;
relayd->relayd_session_id = relayd_session_id;
break;
case LTTNG_STREAM_DATA:
/* Copy received lttcomm socket */
- lttcomm_copy_sock(&relayd->data_sock.sock, &relayd_sock->sock);
- ret = lttcomm_create_sock(&relayd->data_sock.sock);
- /* Handle create_sock error. */
- if (ret < 0) {
- ret_code = LTTCOMM_CONSUMERD_ENOMEM;
- goto error;
- }
- /*
- * Close the socket created internally by
- * lttcomm_create_sock, so we can replace it by the one
- * received from sessiond.
- */
- if (close(relayd->data_sock.sock.fd)) {
- PERROR("close");
- }
-
- /* Assign new file descriptor */
- relayd->data_sock.sock.fd = fd;
+ ret = lttcomm_populate_sock_from_open_socket(
+ &relayd->data_sock.sock, fd,
+ relayd_socket_protocol);
/* Assign version values. */
- relayd->data_sock.major = relayd_sock->major;
- relayd->data_sock.minor = relayd_sock->minor;
+ relayd->data_sock.major = relayd_version_major;
+ relayd->data_sock.minor = relayd_version_minor;
break;
default:
ERR("Unknown relayd socket type (%d)", sock_type);
goto error;
}
+ if (ret < 0) {
+ ret_code = LTTCOMM_CONSUMERD_FATAL;
+ goto error;
+ }
+
DBG("Consumer %s socket created successfully with net idx %" PRIu64 " (fd: %d)",
sock_type == LTTNG_STREAM_CONTROL ? "control" : "data",
relayd->net_seq_idx, fd);
#include <limits.h>
#include <poll.h>
+#include <stdint.h>
#include <unistd.h>
#include <urcu/list.h>
struct lttng_consumer_local_data *ctx,
bool locked_by_caller);
int lttng_consumer_on_recv_stream(struct lttng_consumer_stream *stream);
-void consumer_add_relayd_socket(uint64_t net_seq_idx, int sock_type,
- struct lttng_consumer_local_data *ctx, int sock,
- struct pollfd *consumer_sockpoll, struct lttcomm_relayd_sock *relayd_sock,
- uint64_t sessiond_id, uint64_t relayd_session_id);
+void consumer_add_relayd_socket(uint64_t net_seq_idx,
+ int sock_type,
+ struct lttng_consumer_local_data *ctx,
+ int sock,
+ struct pollfd *consumer_sockpoll,
+ uint64_t sessiond_id,
+ uint64_t relayd_session_id,
+ uint32_t relayd_version_major,
+ uint32_t relayd_version_minor,
+ enum lttcomm_sock_proto relayd_socket_protocol);
void consumer_flag_relayd_for_destroy(
struct consumer_relayd_sock_pair *relayd);
int consumer_data_pending(uint64_t id);
switch (msg.cmd_type) {
case LTTNG_CONSUMER_ADD_RELAYD_SOCKET:
{
+ uint32_t major = msg.u.relayd_sock.major;
+ uint32_t minor = msg.u.relayd_sock.minor;
+ enum lttcomm_sock_proto protocol = (enum lttcomm_sock_proto)
+ msg.u.relayd_sock.relayd_socket_protocol;
+
/* Session daemon status message are handled in the following call. */
consumer_add_relayd_socket(msg.u.relayd_sock.net_index,
- msg.u.relayd_sock.type, ctx, sock, consumer_sockpoll,
- &msg.u.relayd_sock.sock, msg.u.relayd_sock.session_id,
- msg.u.relayd_sock.relayd_session_id);
+ msg.u.relayd_sock.type, ctx, sock,
+ consumer_sockpoll, msg.u.relayd_sock.session_id,
+ msg.u.relayd_sock.relayd_session_id, major,
+ minor, protocol);
goto end_nosignal;
}
case LTTNG_CONSUMER_ADD_CHANNEL:
*
*/
+#include <sys/socket.h>
#define _LGPL_SOURCE
#include <limits.h>
#include <stdio.h>
{
return network_timeout;
}
+
+/*
+ * Only valid for an ipv4 and ipv6 bound socket that is already connected to its
+ * peer.
+ */
+int lttcomm_populate_sock_from_open_socket(
+ struct lttcomm_sock *sock,
+ int fd,
+ enum lttcomm_sock_proto protocol)
+{
+ int ret = 0;
+ socklen_t storage_len;
+ struct sockaddr_storage storage = { 0 };
+
+ assert(sock);
+ assert(fd >= 0);
+
+ sock->proto = protocol;
+
+ storage_len = sizeof(storage);
+ ret = getpeername(fd, (struct sockaddr *) &storage,
+ &storage_len);
+ if (ret) {
+ ERR("Failed to get peer info for socket %d (errno: %d)", fd,
+ errno);
+ ret = -1;
+ goto end;
+ }
+
+ if (storage_len > sizeof(storage)) {
+ ERR("Failed to get peer info for socket %d: storage size is too small", fd);
+ ret = -1;
+ goto end;
+ }
+
+ switch (storage.ss_family) {
+ case AF_INET:
+ sock->sockaddr.type = LTTCOMM_INET;
+ memcpy(&sock->sockaddr.addr, &storage,
+ sizeof(struct sockaddr_in));
+ break;
+ case AF_INET6:
+ sock->sockaddr.type = LTTCOMM_INET6;
+ memcpy(&sock->sockaddr.addr, &storage,
+ sizeof(struct sockaddr_in6));
+ break;
+ default:
+ abort();
+ break;
+ }
+
+ /* Create a valid socket object with a temporary fd. */
+ ret = lttcomm_create_sock(sock);
+ if (ret < 0) {
+ ERR("Failed to create temporary socket object");
+ ret = -1;
+ goto end;
+ }
+
+ /* Substitute the fd. */
+ if (sock->ops->close(sock)) {
+ ret = -1;
+ goto end;
+ }
+ sock->fd = fd;
+
+end:
+ return ret;
+}
#include <arpa/inet.h>
#include <netinet/in.h>
+#include <stdint.h>
#include <sys/un.h>
#include "inet.h"
struct sockaddr_in sin;
struct sockaddr_in6 sin6;
} addr;
-} LTTNG_PACKED;
+};
struct lttcomm_sock {
int32_t fd;
enum lttcomm_sock_proto proto;
struct lttcomm_sockaddr sockaddr;
const struct lttcomm_proto_ops *ops;
-} LTTNG_PACKED;
+};
/*
* Relayd sock. Adds the protocol version to use for the communications with
struct lttcomm_sock sock;
uint32_t major;
uint32_t minor;
-} LTTNG_PACKED;
+};
struct lttcomm_net_family {
int family;
struct {
uint64_t net_index;
enum lttng_stream_type type;
- /* Open socket to the relayd */
- struct lttcomm_relayd_sock sock;
+ uint32_t major;
+ uint32_t minor;
+ uint8_t relayd_socket_protocol;
/* Tracing session id associated to the relayd. */
uint64_t session_id;
/* Relayd session id, only used with control socket. */
const char *ip, unsigned int port);
struct lttcomm_sock *lttcomm_alloc_sock(enum lttcomm_sock_proto proto);
+int lttcomm_populate_sock_from_open_socket(struct lttcomm_sock *sock,
+ int fd,
+ enum lttcomm_sock_proto protocol);
int lttcomm_create_sock(struct lttcomm_sock *sock);
struct lttcomm_sock *lttcomm_alloc_sock_from_uri(struct lttng_uri *uri);
void lttcomm_destroy_sock(struct lttcomm_sock *sock);
switch (msg.cmd_type) {
case LTTNG_CONSUMER_ADD_RELAYD_SOCKET:
{
+ uint32_t major = msg.u.relayd_sock.major;
+ uint32_t minor = msg.u.relayd_sock.minor;
+ enum lttcomm_sock_proto protocol =
+ (enum lttcomm_sock_proto) msg.u.relayd_sock
+ .relayd_socket_protocol;
+
/* Session daemon status message are handled in the following call. */
consumer_add_relayd_socket(msg.u.relayd_sock.net_index,
- msg.u.relayd_sock.type, ctx, sock, consumer_sockpoll,
- &msg.u.relayd_sock.sock, msg.u.relayd_sock.session_id,
- msg.u.relayd_sock.relayd_session_id);
+ msg.u.relayd_sock.type, ctx, sock,
+ consumer_sockpoll, msg.u.relayd_sock.session_id,
+ msg.u.relayd_sock.relayd_session_id, major,
+ minor, protocol);
goto end_nosignal;
}
case LTTNG_CONSUMER_DESTROY_RELAYD:
projects / lttng-tools.git / commitdiff
