[PATCH] Multipath: Remove duplicated memset() for multipathd show command.
[PATCH] multipath-tools: New way to limit the IPC command length.
[PATCH] multipath-tools: Perform socket client uid check on IPC commands.
Signed-off-by: Gris Ge <fge@redhat.com>
---
libmultipath/print.c | 10 ----------
libmultipath/uxsock.c | 38 +++++++++++++++++++++++++++++---------
libmultipath/uxsock.h | 9 +++++++++
multipathd/main.c | 15 +++++++++++++--
multipathd/uxlsnr.c | 31 ++++++++++++++++++++++++++-----
multipathd/uxlsnr.h | 8 +++++---
6 files changed, 82 insertions(+), 29 deletions(-)
Index: multipath-tools-130222/libmultipath/print.c
===================================================================
--- multipath-tools-130222.orig/libmultipath/print.c
+++ multipath-tools-130222/libmultipath/print.c
@@ -771,8 +771,6 @@ snprint_multipath_header (char * line, i
int fwd;
struct multipath_data * data;
- memset(line, 0, len);
-
do {
if (!TAIL)
break;
@@ -806,8 +804,6 @@ snprint_multipath (char * line, int len,
struct multipath_data * data;
char buff[MAX_FIELD_LEN] = {};
- memset(line, 0, len);
-
do {
if (!TAIL)
break;
@@ -842,8 +838,6 @@ snprint_path_header (char * line, int le
int fwd;
struct path_data * data;
- memset(line, 0, len);
-
do {
if (!TAIL)
break;
@@ -877,8 +871,6 @@ snprint_path (char * line, int len, char
struct path_data * data;
char buff[MAX_FIELD_LEN];
- memset(line, 0, len);
-
do {
if (!TAIL)
break;
@@ -914,8 +906,6 @@ snprint_pathgroup (char * line, int len,
struct pathgroup_data * data;
char buff[MAX_FIELD_LEN];
- memset(line, 0, len);
-
do {
if (!TAIL)
break;
Index: multipath-tools-130222/libmultipath/uxsock.c
===================================================================
--- multipath-tools-130222.orig/libmultipath/uxsock.c
+++ multipath-tools-130222/libmultipath/uxsock.c
@@ -20,6 +20,15 @@
#include "memory.h"
#include "uxsock.h"
+
+/*
+ * Code is similar with mpath_recv_reply() with data size limitation
+ * and debug-able malloc.
+ * When limit == 0, it means no limit on data size, used for socket client
+ * to receiving data from multipathd.
+ */
+static int _recv_packet(int fd, char **buf, ssize_t limit);
+
/*
* create a unix domain socket and start listening on it
* return a file descriptor open on the socket
@@ -95,27 +104,38 @@ int send_packet(int fd, const char *buf)
return ret;
}
-/*
- * receive a packet in length prefix format
- */
-int recv_packet(int fd, char **buf)
+static int _recv_packet(int fd, char **buf, ssize_t limit)
{
- int err;
- ssize_t len;
+ int err = 0;
+ ssize_t len = 0;
unsigned int timeout = DEFAULT_REPLY_TIMEOUT;
*buf = NULL;
len = mpath_recv_reply_len(fd, timeout);
if (len <= 0)
return len;
+ if ((limit > 0) && (len > limit))
+ return -EINVAL;
(*buf) = MALLOC(len);
if (!*buf)
return -ENOMEM;
err = mpath_recv_reply_data(fd, *buf, len, timeout);
- if (err) {
+ if (err != 0) {
FREE(*buf);
(*buf) = NULL;
- return err;
}
- return 0;
+ return err;
+}
+
+/*
+ * receive a packet in length prefix format
+ */
+int recv_packet(int fd, char **buf)
+{
+ return _recv_packet(fd, buf, 0 /* no limit */);
+}
+
+int recv_packet_from_client(int fd, char **buf)
+{
+ return _recv_packet(fd, buf, _MAX_CMD_LEN);
}
Index: multipath-tools-130222/libmultipath/uxsock.h
===================================================================
--- multipath-tools-130222.orig/libmultipath/uxsock.h
+++ multipath-tools-130222/libmultipath/uxsock.h
@@ -3,3 +3,12 @@ int ux_socket_listen(const char *name);
int send_packet(int fd, const char *buf);
int recv_packet(int fd, char **buf);
size_t write_all(int fd, const void *buf, size_t len);
+
+#define _MAX_CMD_LEN 512
+
+/*
+ * Used for receiving socket command from untrusted socket client where data
+ * size is restricted to 512(_MAX_CMD_LEN) at most.
+ * Return -EINVAL if data length requested by client exceeded the _MAX_CMD_LEN.
+ */
+int recv_packet_from_client(int fd, char **buf);
Index: multipath-tools-130222/multipathd/main.c
===================================================================
--- multipath-tools-130222.orig/multipathd/main.c
+++ multipath-tools-130222/multipathd/main.c
@@ -18,6 +18,7 @@
#include <linux/oom.h>
#include <libudev.h>
#include <semaphore.h>
+#include <stdbool.h>
#include <mpath_persist.h>
#include "prioritizers/alua_rtpg.h"
@@ -859,7 +860,8 @@ map_discovery (struct vectors * vecs)
}
int
-uxsock_trigger (char * str, char ** reply, int * len, void * trigger_data)
+uxsock_trigger (char * str, char ** reply, int * len, bool is_root,
+ void * trigger_data)
{
struct vectors * vecs;
int r;
@@ -872,6 +874,15 @@ uxsock_trigger (char * str, char ** repl
lock(vecs->lock);
pthread_testcancel();
+ if ((str != NULL) && (is_root == false) &&
+ (strncmp(str, "list", strlen("list")) != 0) &&
+ (strncmp(str, "show", strlen("show")) != 0)) {
+ *reply = STRDUP("permission deny: need to be root");
+ *len = strlen(*reply) + 1;
+ r = 1;
+ goto out;
+ }
+
r = parse_cmd(str, reply, len, vecs);
if (r > 0) {
@@ -885,7 +896,7 @@ uxsock_trigger (char * str, char ** repl
r = 0;
}
/* else if (r < 0) leave *reply alone */
-
+out:
lock_cleanup_pop(vecs->lock);
return r;
}
Index: multipath-tools-130222/multipathd/uxlsnr.c
===================================================================
--- multipath-tools-130222.orig/multipathd/uxlsnr.c
+++ multipath-tools-130222/multipathd/uxlsnr.c
@@ -21,6 +21,7 @@
#include <sys/un.h>
#include <sys/poll.h>
#include <signal.h>
+#include <stdbool.h>
#include <checkers.h>
#include <memory.h>
#include <debug.h>
@@ -48,6 +49,23 @@ struct pollfd *polls;
volatile sig_atomic_t reconfig_sig = 0;
volatile sig_atomic_t log_reset_sig = 0;
+static bool _socket_client_is_root(int fd);
+
+static bool _socket_client_is_root(int fd)
+{
+ socklen_t len = 0;
+ struct ucred uc;
+
+ len = sizeof(struct ucred);
+ if ((fd >= 0) &&
+ (getsockopt(fd, SOL_SOCKET, SO_PEERCRED, &uc, &len) == 0) &&
+ (uc.uid == 0))
+ return true;
+
+ /* Treat error as not root client */
+ return false;
+}
+
/*
* handle a new client joining
*/
@@ -105,8 +123,7 @@ void uxsock_cleanup(void *arg)
/*
* entry point
*/
-void * uxsock_listen(int (*uxsock_trigger)(char *, char **, int *, void *),
- void * trigger_data)
+void * uxsock_listen(uxsock_trigger_fn uxsock_trigger, void * trigger_data)
{
int ux_sock;
int rlen;
@@ -171,12 +188,16 @@ void * uxsock_listen(int (*uxsock_trigge
struct client *next = c->next;
if (polls[i].revents & POLLIN) {
- if (recv_packet(c->fd, &inbuf) != 0) {
+ if (recv_packet_from_client(c->fd,
+ &inbuf) != 0) {
dead_client(c);
+ } else if (!inbuf) {
+ condlog(4, "recv_packet_from_client "
+ "get null request");
+ continue;
} else {
condlog(4, "Got request [%s]", inbuf);
- uxsock_trigger(inbuf, &reply, &rlen,
- trigger_data);
+ uxsock_trigger(inbuf, &reply, &rlen, _socket_client_is_root(c->fd), trigger_data);
if (reply) {
if (send_packet(c->fd,
reply) != 0) {
Index: multipath-tools-130222/multipathd/uxlsnr.h
===================================================================
--- multipath-tools-130222.orig/multipathd/uxlsnr.h
+++ multipath-tools-130222/multipathd/uxlsnr.h
@@ -1,9 +1,11 @@
#ifndef _UXLSNR_H
#define _UXLSNR_H
-void * uxsock_listen(int (*uxsock_trigger)
- (char *, char **, int *, void *),
- void * trigger_data);
+#include <stdbool.h>
+
+typedef int (uxsock_trigger_fn)(char *, char **, int *, bool, void *);
+
+void *uxsock_listen(uxsock_trigger_fn uxsock_trigger, void * trigger_data);
extern volatile sig_atomic_t reconfig_sig;
extern volatile sig_atomic_t log_reset_sig;