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authorFlorian Weimer <fweimer@redhat.com>2017-02-28 15:28:45 +0100
committerFlorian Weimer <fweimer@redhat.com>2017-02-28 15:36:17 +0100
commitcf0bd2f73bd65beab613865bba567d7787836888 (patch)
tree8cde5a2a9547382fac6546c9397aebbb914cb485 /sunrpc
parent37fb019cb02656d0ce0b8d40d56fe8c42f0d1658 (diff)
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sunrpc: Improvements for UDP client timeout handling [BZ #20257]
This commit fixes various aspects in the UDP client timeout handling. Timeouts are now applied in a more consistent fashion. Discarded UDP packets no longer prevent the timeout from happening at all.
Diffstat (limited to 'sunrpc')
-rw-r--r--sunrpc/Makefile10
-rw-r--r--sunrpc/clnt_udp.c127
-rw-r--r--sunrpc/tst-udp-garbage.c104
-rw-r--r--sunrpc/tst-udp-nonblocking.c333
-rw-r--r--sunrpc/tst-udp-timeout.c402
5 files changed, 919 insertions, 57 deletions
diff --git a/sunrpc/Makefile b/sunrpc/Makefile
index 0249e10..063a761 100644
--- a/sunrpc/Makefile
+++ b/sunrpc/Makefile
@@ -93,12 +93,13 @@ rpcgen-objs = rpc_main.o rpc_hout.o rpc_cout.o rpc_parse.o \
extra-objs = $(rpcgen-objs) $(addprefix cross-,$(rpcgen-objs))
others += rpcgen
-tests = tst-xdrmem tst-xdrmem2 test-rpcent tst-udp-error
+tests = tst-xdrmem tst-xdrmem2 test-rpcent tst-udp-error tst-udp-timeout \
+ tst-udp-nonblocking
xtests := tst-getmyaddr
ifeq ($(have-thread-library),yes)
xtests += thrsvc
-tests += tst-svc_register
+tests += tst-svc_register tst-udp-garbage
endif
ifeq ($(run-built-tests),yes)
@@ -238,3 +239,8 @@ $(rpcgen-tests): $(objpfx)%.out: %.x $(objpfx)rpcgen
$(built-program-cmd) -c $< -o $@; \
$(evaluate-test)
endif
+
+$(objpfx)tst-udp-timeout: $(common-objpfx)linkobj/libc.so
+$(objpfx)tst-udp-nonblocking: $(common-objpfx)linkobj/libc.so
+$(objpfx)tst-udp-garbage: \
+ $(common-objpfx)linkobj/libc.so $(shared-thread-library)
diff --git a/sunrpc/clnt_udp.c b/sunrpc/clnt_udp.c
index 1de25cb..6ce16eb 100644
--- a/sunrpc/clnt_udp.c
+++ b/sunrpc/clnt_udp.c
@@ -55,6 +55,7 @@
#endif
#include <kernel-features.h>
+#include <inet/net-internal.h>
extern u_long _create_xid (void);
@@ -80,7 +81,9 @@ static const struct clnt_ops udp_ops =
};
/*
- * Private data kept per client handle
+ * Private data kept per client handle. This private struct is
+ * unfortunately part of the ABI; ypbind contains a copy of it and
+ * accesses it through CLIENT::cl_private field.
*/
struct cu_data
{
@@ -278,28 +281,38 @@ clntudp_call (/* client handle */
int inlen;
socklen_t fromlen;
struct pollfd fd;
- int milliseconds = (cu->cu_wait.tv_sec * 1000) +
- (cu->cu_wait.tv_usec / 1000);
struct sockaddr_in from;
struct rpc_msg reply_msg;
XDR reply_xdrs;
- struct timeval time_waited;
bool_t ok;
int nrefreshes = 2; /* number of times to refresh cred */
- struct timeval timeout;
int anyup; /* any network interface up */
- if (cu->cu_total.tv_usec == -1)
- {
- timeout = utimeout; /* use supplied timeout */
- }
- else
+ struct deadline_current_time current_time = __deadline_current_time ();
+ struct deadline total_deadline; /* Determined once by overall timeout. */
+ struct deadline response_deadline; /* Determined anew for each query. */
+
+ /* Choose the timeout value. For non-sending usage (xargs == NULL),
+ the total deadline does not matter, only cu->cu_wait is used
+ below. */
+ if (xargs != NULL)
{
- timeout = cu->cu_total; /* use default timeout */
+ struct timeval tv;
+ if (cu->cu_total.tv_usec == -1)
+ /* Use supplied timeout. */
+ tv = utimeout;
+ else
+ /* Use default timeout. */
+ tv = cu->cu_total;
+ if (!__is_timeval_valid_timeout (tv))
+ return (cu->cu_error.re_status = RPC_TIMEDOUT);
+ total_deadline = __deadline_from_timeval (current_time, tv);
}
- time_waited.tv_sec = 0;
- time_waited.tv_usec = 0;
+ /* Guard against bad timeout specification. */
+ if (!__is_timeval_valid_timeout (cu->cu_wait))
+ return (cu->cu_error.re_status = RPC_TIMEDOUT);
+
call_again:
xdrs = &(cu->cu_outxdrs);
if (xargs == NULL)
@@ -325,27 +338,46 @@ send_again:
return (cu->cu_error.re_status = RPC_CANTSEND);
}
- /*
- * Hack to provide rpc-based message passing
- */
- if (timeout.tv_sec == 0 && timeout.tv_usec == 0)
- {
- return (cu->cu_error.re_status = RPC_TIMEDOUT);
- }
+ /* sendto may have blocked, so recompute the current time. */
+ current_time = __deadline_current_time ();
get_reply:
- /*
- * sub-optimal code appears here because we have
- * some clock time to spare while the packets are in flight.
- * (We assume that this is actually only executed once.)
- */
+ response_deadline = __deadline_from_timeval (current_time, cu->cu_wait);
+
reply_msg.acpted_rply.ar_verf = _null_auth;
reply_msg.acpted_rply.ar_results.where = resultsp;
reply_msg.acpted_rply.ar_results.proc = xresults;
fd.fd = cu->cu_sock;
fd.events = POLLIN;
anyup = 0;
+
+ /* Per-response retry loop. current_time must be up-to-date at the
+ top of the loop. */
for (;;)
{
+ int milliseconds;
+ if (xargs != NULL)
+ {
+ if (__deadline_elapsed (current_time, total_deadline))
+ /* Overall timeout expired. */
+ return (cu->cu_error.re_status = RPC_TIMEDOUT);
+ milliseconds = __deadline_to_ms
+ (current_time, __deadline_first (total_deadline,
+ response_deadline));
+ if (milliseconds == 0)
+ /* Per-query timeout expired. */
+ goto send_again;
+ }
+ else
+ {
+ /* xatgs == NULL. Collect a response without sending a
+ query. In this mode, we need to ignore the total
+ deadline. */
+ milliseconds = __deadline_to_ms (current_time, response_deadline);
+ if (milliseconds == 0)
+ /* Cannot send again, so bail out. */
+ return (cu->cu_error.re_status = RPC_CANTSEND);
+ }
+
switch (__poll (&fd, 1, milliseconds))
{
@@ -356,27 +388,10 @@ send_again:
if (!anyup)
return (cu->cu_error.re_status = RPC_CANTRECV);
}
-
- time_waited.tv_sec += cu->cu_wait.tv_sec;
- time_waited.tv_usec += cu->cu_wait.tv_usec;
- while (time_waited.tv_usec >= 1000000)
- {
- time_waited.tv_sec++;
- time_waited.tv_usec -= 1000000;
- }
- if ((time_waited.tv_sec < timeout.tv_sec) ||
- ((time_waited.tv_sec == timeout.tv_sec) &&
- (time_waited.tv_usec < timeout.tv_usec)))
- goto send_again;
- return (cu->cu_error.re_status = RPC_TIMEDOUT);
-
- /*
- * buggy in other cases because time_waited is not being
- * updated.
- */
+ goto next_response;
case -1:
if (errno == EINTR)
- continue;
+ goto next_response;
cu->cu_error.re_errno = errno;
return (cu->cu_error.re_status = RPC_CANTRECV);
}
@@ -440,20 +455,22 @@ send_again:
if (inlen < 0)
{
if (errno == EWOULDBLOCK)
- continue;
+ goto next_response;
cu->cu_error.re_errno = errno;
return (cu->cu_error.re_status = RPC_CANTRECV);
}
- if (inlen < 4)
- continue;
-
- /* see if reply transaction id matches sent id.
- Don't do this if we only wait for a replay */
- if (xargs != NULL
- && memcmp (cu->cu_inbuf, cu->cu_outbuf, sizeof (u_int32_t)) != 0)
- continue;
- /* we now assume we have the proper reply */
- break;
+ /* Accept the response if the packet is sufficiently long and
+ the transaction ID matches the query (if available). */
+ if (inlen >= 4
+ && (xargs == NULL
+ || memcmp (cu->cu_inbuf, cu->cu_outbuf,
+ sizeof (u_int32_t)) == 0))
+ break;
+
+ next_response:
+ /* Update the current time because poll and recvmsg waited for
+ an unknown time. */
+ current_time = __deadline_current_time ();
}
/*
diff --git a/sunrpc/tst-udp-garbage.c b/sunrpc/tst-udp-garbage.c
new file mode 100644
index 0000000..4abda93
--- /dev/null
+++ b/sunrpc/tst-udp-garbage.c
@@ -0,0 +1,104 @@
+/* Test that garbage packets do not affect timeout handling.
+ Copyright (C) 2017 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+
+ The GNU C Library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 of the License, or (at your option) any later version.
+
+ The GNU C Library is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with the GNU C Library; if not, see
+ <http://www.gnu.org/licenses/>. */
+
+#include <netinet/in.h>
+#include <rpc/clnt.h>
+#include <rpc/svc.h>
+#include <stdbool.h>
+#include <support/check.h>
+#include <support/namespace.h>
+#include <support/xsocket.h>
+#include <support/xthread.h>
+#include <sys/socket.h>
+#include <unistd.h>
+
+/* Descriptor for the server UDP socket. */
+static int server_fd;
+
+static void *
+garbage_sender_thread (void *unused)
+{
+ while (true)
+ {
+ struct sockaddr_storage sa;
+ socklen_t salen = sizeof (sa);
+ char buf[1];
+ if (recvfrom (server_fd, buf, sizeof (buf), 0,
+ (struct sockaddr *) &sa, &salen) < 0)
+ FAIL_EXIT1 ("recvfrom: %m");
+
+ /* Send garbage packets indefinitely. */
+ buf[0] = 0;
+ while (true)
+ {
+ /* sendto can fail if the client closed the socket. */
+ if (sendto (server_fd, buf, sizeof (buf), 0,
+ (struct sockaddr *) &sa, salen) < 0)
+ break;
+
+ /* Wait a bit, to avoid burning too many CPU cycles in a
+ tight loop. The wait period must be much shorter than
+ the client timeouts configured below. */
+ usleep (50 * 1000);
+ }
+ }
+}
+
+static int
+do_test (void)
+{
+ support_become_root ();
+ support_enter_network_namespace ();
+
+ server_fd = xsocket (AF_INET, SOCK_DGRAM | SOCK_CLOEXEC, IPPROTO_UDP);
+ struct sockaddr_in server_address =
+ {
+ .sin_family = AF_INET,
+ .sin_addr.s_addr = htonl (INADDR_LOOPBACK),
+ };
+ xbind (server_fd,
+ (struct sockaddr *) &server_address, sizeof (server_address));
+ {
+ socklen_t sinlen = sizeof (server_address);
+ xgetsockname (server_fd, (struct sockaddr *) &server_address, &sinlen);
+ TEST_VERIFY (sizeof (server_address) == sinlen);
+ }
+
+ /* Garbage packet source. */
+ xpthread_detach (xpthread_create (NULL, garbage_sender_thread, NULL));
+
+ /* Test client. Use an arbitrary timeout of one second, which is
+ much longer than the garbage packet interval, but still
+ reasonably short, so that the test completes quickly. */
+ int client_fd = RPC_ANYSOCK;
+ CLIENT *clnt = clntudp_create (&server_address,
+ 1, 2, /* Arbitrary RPC endpoint numbers. */
+ (struct timeval) { 1, 0 },
+ &client_fd);
+ if (clnt == NULL)
+ FAIL_EXIT1 ("clntudp_create: %m");
+
+ TEST_VERIFY (clnt_call (clnt, 3, /* Arbitrary RPC procedure number. */
+ (xdrproc_t) xdr_void, NULL,
+ (xdrproc_t) xdr_void, NULL,
+ ((struct timeval) { 1, 0 })));
+
+ return 0;
+}
+
+#include <support/test-driver.c>
diff --git a/sunrpc/tst-udp-nonblocking.c b/sunrpc/tst-udp-nonblocking.c
new file mode 100644
index 0000000..1d6a7f4
--- /dev/null
+++ b/sunrpc/tst-udp-nonblocking.c
@@ -0,0 +1,333 @@
+/* Test non-blocking use of the UDP client.
+ Copyright (C) 2017 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+
+ The GNU C Library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 of the License, or (at your option) any later version.
+
+ The GNU C Library is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with the GNU C Library; if not, see
+ <http://www.gnu.org/licenses/>. */
+
+#include <netinet/in.h>
+#include <rpc/clnt.h>
+#include <rpc/svc.h>
+#include <stdbool.h>
+#include <string.h>
+#include <support/check.h>
+#include <support/namespace.h>
+#include <support/test-driver.h>
+#include <support/xsocket.h>
+#include <support/xunistd.h>
+#include <sys/socket.h>
+#include <time.h>
+#include <unistd.h>
+
+/* Test data serialization and deserialization. */
+
+struct test_query
+{
+ uint32_t a;
+ uint32_t b;
+ uint32_t timeout_ms;
+};
+
+static bool_t
+xdr_test_query (XDR *xdrs, void *data, ...)
+{
+ struct test_query *p = data;
+ return xdr_uint32_t (xdrs, &p->a)
+ && xdr_uint32_t (xdrs, &p->b)
+ && xdr_uint32_t (xdrs, &p->timeout_ms);
+}
+
+struct test_response
+{
+ uint32_t server_id;
+ uint32_t seq;
+ uint32_t sum;
+};
+
+static bool_t
+xdr_test_response (XDR *xdrs, void *data, ...)
+{
+ struct test_response *p = data;
+ return xdr_uint32_t (xdrs, &p->server_id)
+ && xdr_uint32_t (xdrs, &p->seq)
+ && xdr_uint32_t (xdrs, &p->sum);
+}
+
+/* Implementation of the test server. */
+
+enum
+ {
+ /* Number of test servers to run. */
+ SERVER_COUNT = 3,
+
+ /* RPC parameters, chosen at random. */
+ PROGNUM = 8242,
+ VERSNUM = 19654,
+
+ /* Main RPC operation. */
+ PROC_ADD = 1,
+
+ /* Request process termination. */
+ PROC_EXIT,
+
+ /* Special exit status to mark successful processing. */
+ EXIT_MARKER = 55,
+ };
+
+/* Set by the parent process to tell test servers apart. */
+static int server_id;
+
+/* Implementation of the test server. */
+static void
+server_dispatch (struct svc_req *request, SVCXPRT *transport)
+{
+ /* Query sequence number. */
+ static uint32_t seq = 0;
+ ++seq;
+ static bool proc_add_seen;
+
+ if (test_verbose)
+ printf ("info: server_dispatch server_id=%d seq=%u rq_proc=%lu\n",
+ server_id, seq, request->rq_proc);
+
+ switch (request->rq_proc)
+ {
+ case PROC_ADD:
+ {
+ struct test_query query;
+ memset (&query, 0xc0, sizeof (query));
+ TEST_VERIFY_EXIT
+ (svc_getargs (transport, xdr_test_query,
+ (void *) &query));
+
+ if (test_verbose)
+ printf (" a=%u b=%u timeout_ms=%u\n",
+ query.a, query.b, query.timeout_ms);
+
+ usleep (query.timeout_ms * 1000);
+
+ struct test_response response =
+ {
+ .server_id = server_id,
+ .seq = seq,
+ .sum = query.a + query.b,
+ };
+ TEST_VERIFY (svc_sendreply (transport, xdr_test_response,
+ (void *) &response));
+ if (test_verbose)
+ printf (" server id %d response seq=%u sent\n", server_id, seq);
+ proc_add_seen = true;
+ }
+ break;
+
+ case PROC_EXIT:
+ TEST_VERIFY (proc_add_seen);
+ TEST_VERIFY (svc_sendreply (transport, (xdrproc_t) xdr_void, NULL));
+ _exit (EXIT_MARKER);
+ break;
+
+ default:
+ FAIL_EXIT1 ("invalid rq_proc value: %lu", request->rq_proc);
+ break;
+ }
+}
+
+/* Return the number seconds since an arbitrary point in time. */
+static double
+get_ticks (void)
+{
+ {
+ struct timespec ts;
+ if (clock_gettime (CLOCK_MONOTONIC, &ts) == 0)
+ return ts.tv_sec + ts.tv_nsec * 1e-9;
+ }
+ {
+ struct timeval tv;
+ TEST_VERIFY_EXIT (gettimeofday (&tv, NULL) == 0);
+ return tv.tv_sec + tv.tv_usec * 1e-6;
+ }
+}
+
+static int
+do_test (void)
+{
+ support_become_root ();
+ support_enter_network_namespace ();
+
+ /* Information about the test servers. */
+ struct
+ {
+ SVCXPRT *transport;
+ struct sockaddr_in address;
+ pid_t pid;
+ uint32_t xid;
+ } servers[SERVER_COUNT];
+
+ /* Spawn the test servers. */
+ for (int i = 0; i < SERVER_COUNT; ++i)
+ {
+ servers[i].transport = svcudp_create (RPC_ANYSOCK);
+ TEST_VERIFY_EXIT (servers[i].transport != NULL);
+ servers[i].address = (struct sockaddr_in)
+ {
+ .sin_family = AF_INET,
+ .sin_addr.s_addr = htonl (INADDR_LOOPBACK),
+ .sin_port = htons (servers[i].transport->xp_port),
+ };
+ servers[i].xid = 0xabcd0101 + i;
+ if (test_verbose)
+ printf ("info: setting up server %d xid=%x on port %d\n",
+ i, servers[i].xid, servers[i].transport->xp_port);
+
+ server_id = i;
+ servers[i].pid = xfork ();
+ if (servers[i].pid == 0)
+ {
+ TEST_VERIFY (svc_register (servers[i].transport,
+ PROGNUM, VERSNUM, server_dispatch, 0));
+ svc_run ();
+ FAIL_EXIT1 ("supposed to be unreachable");
+ }
+ /* We need to close the socket so that we do not accidentally
+ consume the request. */
+ TEST_VERIFY (close (servers[i].transport->xp_sock) == 0);
+ }
+
+
+ /* The following code mirrors what ypbind does. */
+
+ /* Copied from clnt_udp.c (like ypbind). */
+ struct cu_data
+ {
+ int cu_sock;
+ bool_t cu_closeit;
+ struct sockaddr_in cu_raddr;
+ int cu_rlen;
+ struct timeval cu_wait;
+ struct timeval cu_total;
+ struct rpc_err cu_error;
+ XDR cu_outxdrs;
+ u_int cu_xdrpos;
+ u_int cu_sendsz;
+ char *cu_outbuf;
+ u_int cu_recvsz;
+ char cu_inbuf[1];
+ };
+
+ int client_socket = xsocket (AF_INET, SOCK_DGRAM | SOCK_NONBLOCK, 0);
+ CLIENT *clnt = clntudp_create (&servers[0].address, PROGNUM, VERSNUM,
+ /* 5 seconds per-response timeout. */
+ ((struct timeval) { 5, 0 }),
+ &client_socket);
+ TEST_VERIFY (clnt != NULL);
+ clnt->cl_auth = authunix_create_default ();
+ {
+ struct timeval zero = { 0, 0 };
+ TEST_VERIFY (clnt_control (clnt, CLSET_TIMEOUT, (void *) &zero));
+ }
+
+ /* Poke at internal data structures (like ypbind). */
+ struct cu_data *cu = (struct cu_data *) clnt->cl_private;
+
+ /* Send a ping to each server. */
+ double before_pings = get_ticks ();
+ for (int i = 0; i < SERVER_COUNT; ++i)
+ {
+ if (test_verbose)
+ printf ("info: sending server %d ping\n", i);
+ /* Reset the xid because it is changed by each invocation of
+ clnt_call. Subtract one to compensate for the xid update
+ during the call. */
+ *((u_int32_t *) (cu->cu_outbuf)) = servers[i].xid - 1;
+ cu->cu_raddr = servers[i].address;
+
+ struct test_query query = { .a = 100, .b = i + 1 };
+ if (i == 1)
+ /* Shorter timeout to prefer this server. These timeouts must
+ be much shorter than the 5-second per-response timeout
+ configured with clntudp_create. */
+ query.timeout_ms = 700;
+ else
+ query.timeout_ms = 1400;
+ struct test_response response = { 0 };
+ /* NB: Do not check the return value. The server reply will
+ prove that the call worked. */
+ double before_one_ping = get_ticks ();
+ clnt_call (clnt, PROC_ADD,
+ xdr_test_query, (void *) &query,
+ xdr_test_response, (void *) &response,
+ ((struct timeval) { 0, 0 }));
+ double after_one_ping = get_ticks ();
+ if (test_verbose)
+ printf ("info: non-blocking send took %f seconds\n",
+ after_one_ping - before_one_ping);
+ /* clnt_call should return immediately. Accept some delay in
+ case the process is descheduled. */
+ TEST_VERIFY (after_one_ping - before_one_ping < 0.3);
+ }
+
+ /* Collect the non-blocking response. */
+ if (test_verbose)
+ printf ("info: collecting response\n");
+ struct test_response response = { 0 };
+ TEST_VERIFY
+ (clnt_call (clnt, PROC_ADD, NULL, NULL,
+ xdr_test_response, (void *) &response,
+ ((struct timeval) { 0, 0 })) == RPC_SUCCESS);
+ double after_pings = get_ticks ();
+ if (test_verbose)
+ printf ("info: send/receive took %f seconds\n",
+ after_pings - before_pings);
+ /* Expected timeout is 0.7 seconds. */
+ TEST_VERIFY (0.7 <= after_pings - before_pings);
+ TEST_VERIFY (after_pings - before_pings < 1.2);
+
+ uint32_t xid;
+ memcpy (&xid, &cu->cu_inbuf, sizeof (xid));
+ if (test_verbose)
+ printf ("info: non-blocking response: xid=%x server_id=%u seq=%u sum=%u\n",
+ xid, response.server_id, response.seq, response.sum);
+ /* Check that the reply from the preferred server was used. */
+ TEST_VERIFY (servers[1].xid == xid);
+ TEST_VERIFY (response.server_id == 1);
+ TEST_VERIFY (response.seq == 1);
+ TEST_VERIFY (response.sum == 102);
+
+ auth_destroy (clnt->cl_auth);
+ clnt_destroy (clnt);
+
+ for (int i = 0; i < SERVER_COUNT; ++i)
+ {
+ if (test_verbose)
+ printf ("info: requesting server %d termination\n", i);
+ client_socket = RPC_ANYSOCK;
+ clnt = clntudp_create (&servers[i].address, PROGNUM, VERSNUM,
+ ((struct timeval) { 5, 0 }),
+ &client_socket);
+ TEST_VERIFY_EXIT (clnt != NULL);
+ TEST_VERIFY (clnt_call (clnt, PROC_EXIT,
+ (xdrproc_t) xdr_void, NULL,
+ (xdrproc_t) xdr_void, NULL,
+ ((struct timeval) { 3, 0 })) == RPC_SUCCESS);
+ clnt_destroy (clnt);
+
+ int status;
+ xwaitpid (servers[i].pid, &status, 0);
+ TEST_VERIFY (WIFEXITED (status) && WEXITSTATUS (status) == EXIT_MARKER);
+ }
+
+ return 0;
+}
+
+#include <support/test-driver.c>
diff --git a/sunrpc/tst-udp-timeout.c b/sunrpc/tst-udp-timeout.c
new file mode 100644
index 0000000..db9943a
--- /dev/null
+++ b/sunrpc/tst-udp-timeout.c
@@ -0,0 +1,402 @@
+/* Test timeout handling in the UDP client.
+ Copyright (C) 2017 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+
+ The GNU C Library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 of the License, or (at your option) any later version.
+
+ The GNU C Library is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with the GNU C Library; if not, see
+ <http://www.gnu.org/licenses/>. */
+
+#include <netinet/in.h>
+#include <rpc/clnt.h>
+#include <rpc/svc.h>
+#include <stdbool.h>
+#include <string.h>
+#include <support/check.h>
+#include <support/namespace.h>
+#include <support/test-driver.h>
+#include <support/xsocket.h>
+#include <support/xunistd.h>
+#include <sys/socket.h>
+#include <time.h>
+#include <unistd.h>
+
+/* Test data serialization and deserialization. */
+
+struct test_query
+{
+ uint32_t a;
+ uint32_t b;
+ uint32_t timeout_ms;
+ uint32_t wait_for_seq;
+ uint32_t garbage_packets;
+};
+
+static bool_t
+xdr_test_query (XDR *xdrs, void *data, ...)
+{
+ struct test_query *p = data;
+ return xdr_uint32_t (xdrs, &p->a)
+ && xdr_uint32_t (xdrs, &p->b)
+ && xdr_uint32_t (xdrs, &p->timeout_ms)
+ && xdr_uint32_t (xdrs, &p->wait_for_seq)
+ && xdr_uint32_t (xdrs, &p->garbage_packets);
+}
+
+struct test_response
+{
+ uint32_t seq;
+ uint32_t sum;
+};
+
+static bool_t
+xdr_test_response (XDR *xdrs, void *data, ...)
+{
+ struct test_response *p = data;
+ return xdr_uint32_t (xdrs, &p->seq)
+ && xdr_uint32_t (xdrs, &p->sum);
+}
+
+/* Implementation of the test server. */
+
+enum
+ {
+ /* RPC parameters, chosen at random. */
+ PROGNUM = 15717,
+ VERSNUM = 13689,
+
+ /* Main RPC operation. */
+ PROC_ADD = 1,
+
+ /* Reset the sequence number. */
+ PROC_RESET_SEQ,
+
+ /* Request process termination. */
+ PROC_EXIT,
+
+ /* Special exit status to mark successful processing. */
+ EXIT_MARKER = 55,
+ };
+
+static void
+server_dispatch (struct svc_req *request, SVCXPRT *transport)
+{
+ /* Query sequence number. */
+ static uint32_t seq = 0;
+ ++seq;
+
+ if (test_verbose)
+ printf ("info: server_dispatch seq=%u rq_proc=%lu\n",
+ seq, request->rq_proc);
+
+ switch (request->rq_proc)
+ {
+ case PROC_ADD:
+ {
+ struct test_query query;
+ memset (&query, 0xc0, sizeof (query));
+ TEST_VERIFY_EXIT
+ (svc_getargs (transport, xdr_test_query,
+ (void *) &query));
+
+ if (test_verbose)
+ printf (" a=%u b=%u timeout_ms=%u wait_for_seq=%u"
+ " garbage_packets=%u\n",
+ query.a, query.b, query.timeout_ms, query.wait_for_seq,
+ query.garbage_packets);
+
+ if (seq < query.wait_for_seq)
+ {
+ /* No response at this point. */
+ if (test_verbose)
+ printf (" skipped response\n");
+ break;
+ }
+
+ if (query.garbage_packets > 0)
+ {
+ int per_packet_timeout;
+ if (query.timeout_ms > 0)
+ per_packet_timeout
+ = query.timeout_ms * 1000 / query.garbage_packets;
+ else
+ per_packet_timeout = 0;
+
+ char buf[20];
+ memset (&buf, 0xc0, sizeof (buf));
+ for (int i = 0; i < query.garbage_packets; ++i)
+ {
+ /* 13 is relatively prime to 20 = sizeof (buf) + 1, so
+ the len variable will cover the entire interval
+ [0, 20] if query.garbage_packets is sufficiently
+ large. */
+ size_t len = (i * 13 + 1) % (sizeof (buf) + 1);
+ TEST_VERIFY (sendto (transport->xp_sock,
+ buf, len, MSG_NOSIGNAL,
+ (struct sockaddr *) &transport->xp_raddr,
+ transport->xp_addrlen) == len);
+ if (per_packet_timeout > 0)
+ usleep (per_packet_timeout);
+ }
+ }
+ else if (query.timeout_ms > 0)
+ usleep (query.timeout_ms * 1000);
+
+ struct test_response response =
+ {
+ .seq = seq,
+ .sum = query.a + query.b,
+ };
+ TEST_VERIFY (svc_sendreply (transport, xdr_test_response,
+ (void *) &response));
+ }
+ break;
+
+ case PROC_RESET_SEQ:
+ seq = 0;
+ TEST_VERIFY (svc_sendreply (transport, (xdrproc_t) xdr_void, NULL));
+ break;
+
+ case PROC_EXIT:
+ TEST_VERIFY (svc_sendreply (transport, (xdrproc_t) xdr_void, NULL));
+ _exit (EXIT_MARKER);
+ break;
+
+ default:
+ FAIL_EXIT1 ("invalid rq_proc value: %lu", request->rq_proc);
+ break;
+ }
+}
+
+/* Implementation of the test client. */
+
+static struct test_response
+test_call (CLIENT *clnt, int proc, struct test_query query,
+ struct timeval timeout)
+{
+ if (test_verbose)
+ printf ("info: test_call proc=%d timeout=%lu.%06lu\n",
+ proc, (unsigned long) timeout.tv_sec,
+ (unsigned long) timeout.tv_usec);
+ struct test_response response;
+ TEST_VERIFY_EXIT (clnt_call (clnt, proc,
+ xdr_test_query, (void *) &query,
+ xdr_test_response, (void *) &response,
+ timeout)
+ == RPC_SUCCESS);
+ return response;
+}
+
+static void
+test_call_timeout (CLIENT *clnt, int proc, struct test_query query,
+ struct timeval timeout)
+{
+ struct test_response response;
+ TEST_VERIFY (clnt_call (clnt, proc,
+ xdr_test_query, (void *) &query,
+ xdr_test_response, (void *) &response,
+ timeout)
+ == RPC_TIMEDOUT);
+}
+
+/* Complete one regular RPC call to drain the server socket
+ buffer. Resets the sequence number. */
+static void
+test_call_flush (CLIENT *clnt)
+{
+ /* This needs a longer timeout to flush out all pending requests.
+ The choice of 5 seconds is larger than the per-response timeouts
+ requested via the timeout_ms field. */
+ if (test_verbose)
+ printf ("info: flushing pending queries\n");
+ TEST_VERIFY_EXIT (clnt_call (clnt, PROC_RESET_SEQ,
+ (xdrproc_t) xdr_void, NULL,
+ (xdrproc_t) xdr_void, NULL,
+ ((struct timeval) { 5, 0 }))
+ == RPC_SUCCESS);
+}
+
+/* Return the number seconds since an arbitrary point in time. */
+static double
+get_ticks (void)
+{
+ {
+ struct timespec ts;
+ if (clock_gettime (CLOCK_MONOTONIC, &ts) == 0)
+ return ts.tv_sec + ts.tv_nsec * 1e-9;
+ }
+ {
+ struct timeval tv;
+ TEST_VERIFY_EXIT (gettimeofday (&tv, NULL) == 0);
+ return tv.tv_sec + tv.tv_usec * 1e-6;
+ }
+}
+
+static void
+test_udp_server (int port)
+{
+ struct sockaddr_in sin =
+ {
+ .sin_family = AF_INET,
+ .sin_addr.s_addr = htonl (INADDR_LOOPBACK),
+ .sin_port = htons (port)
+ };
+ int sock = RPC_ANYSOCK;
+
+ /* The client uses a 1.5 second timeout for retries. The timeouts
+ are arbitrary, but chosen so that there is a substantial gap
+ between them, but the total time spent waiting is not too
+ large. */
+ CLIENT *clnt = clntudp_create (&sin, PROGNUM, VERSNUM,
+ (struct timeval) { 1, 500 * 1000 },
+ &sock);
+ TEST_VERIFY_EXIT (clnt != NULL);
+
+ /* Basic call/response test. */
+ struct test_response response = test_call
+ (clnt, PROC_ADD,
+ (struct test_query) { .a = 17, .b = 4 },
+ (struct timeval) { 3, 0 });
+ TEST_VERIFY (response.sum == 21);
+ TEST_VERIFY (response.seq == 1);
+
+ /* Check that garbage packets do not interfere with timeout
+ processing. */
+ double before = get_ticks ();
+ response = test_call
+ (clnt, PROC_ADD,
+ (struct test_query) {
+ .a = 19, .b = 4, .timeout_ms = 500, .garbage_packets = 21,
+ },
+ (struct timeval) { 3, 0 });
+ TEST_VERIFY (response.sum == 23);
+ TEST_VERIFY (response.seq == 2);
+ double after = get_ticks ();
+ if (test_verbose)
+ printf ("info: 21 garbage packets took %f seconds\n", after - before);
+ /* Expected timeout is 0.5 seconds. Add some slack in case process
+ scheduling delays processing the query or response, but do not
+ accept a retry (which would happen at 1.5 seconds). */
+ TEST_VERIFY (0.5 <= after - before);
+ TEST_VERIFY (after - before < 1.2);
+ test_call_flush (clnt);
+
+ /* Check that missing a response introduces a 1.5 second timeout, as
+ requested when calling clntudp_create. */
+ before = get_ticks ();
+ response = test_call
+ (clnt, PROC_ADD,
+ (struct test_query) { .a = 170, .b = 40, .wait_for_seq = 2 },
+ (struct timeval) { 3, 0 });
+ TEST_VERIFY (response.sum == 210);
+ TEST_VERIFY (response.seq == 2);
+ after = get_ticks ();
+ if (test_verbose)
+ printf ("info: skipping one response took %f seconds\n",
+ after - before);
+ /* Expected timeout is 1.5 seconds. Do not accept a second retry
+ (which would happen at 3 seconds). */
+ TEST_VERIFY (1.5 <= after - before);
+ TEST_VERIFY (after - before < 2.9);
+ test_call_flush (clnt);
+
+ /* Check that the overall timeout wins against the per-query
+ timeout. */
+ before = get_ticks ();
+ test_call_timeout
+ (clnt, PROC_ADD,
+ (struct test_query) { .a = 170, .b = 41, .wait_for_seq = 2 },
+ (struct timeval) { 0, 750 * 1000 });
+ after = get_ticks ();
+ if (test_verbose)
+ printf ("info: 0.75 second timeout took %f seconds\n",
+ after - before);
+ TEST_VERIFY (0.75 <= after - before);
+ TEST_VERIFY (after - before < 1.4);
+ test_call_flush (clnt);
+
+ for (int with_garbage = 0; with_garbage < 2; ++with_garbage)
+ {
+ /* Check that no response at all causes the client to bail out. */
+ before = get_ticks ();
+ test_call_timeout
+ (clnt, PROC_ADD,
+ (struct test_query) {
+ .a = 170, .b = 40, .timeout_ms = 1200,
+ .garbage_packets = with_garbage * 21
+ },
+ (struct timeval) { 0, 750 * 1000 });
+ after = get_ticks ();
+ if (test_verbose)
+ printf ("info: test_udp_server: 0.75 second timeout took %f seconds"
+ " (garbage %d)\n",
+ after - before, with_garbage);
+ TEST_VERIFY (0.75 <= after - before);
+ TEST_VERIFY (after - before < 1.4);
+ test_call_flush (clnt);
+
+ /* As above, but check the total timeout. */
+ before = get_ticks ();
+ test_call_timeout
+ (clnt, PROC_ADD,
+ (struct test_query) {
+ .a = 170, .b = 40, .timeout_ms = 3000,
+ .garbage_packets = with_garbage * 30
+ },
+ (struct timeval) { 2, 300 * 1000 });
+ after = get_ticks ();
+ if (test_verbose)
+ printf ("info: test_udp_server: 2.3 second timeout took %f seconds"
+ " (garbage %d)\n",
+ after - before, with_garbage);
+ TEST_VERIFY (2.3 <= after - before);
+ TEST_VERIFY (after - before < 3.0);
+ test_call_flush (clnt);
+ }
+
+ TEST_VERIFY_EXIT (clnt_call (clnt, PROC_EXIT,
+ (xdrproc_t) xdr_void, NULL,
+ (xdrproc_t) xdr_void, NULL,
+ ((struct timeval) { 5, 0 }))
+ == RPC_SUCCESS);
+ clnt_destroy (clnt);
+}
+
+static int
+do_test (void)
+{
+ support_become_root ();
+ support_enter_network_namespace ();
+
+ SVCXPRT *transport = svcudp_create (RPC_ANYSOCK);
+ TEST_VERIFY_EXIT (transport != NULL);
+ TEST_VERIFY (svc_register (transport, PROGNUM, VERSNUM, server_dispatch, 0));
+
+ pid_t pid = xfork ();
+ if (pid == 0)
+ {
+ svc_run ();
+ FAIL_EXIT1 ("supposed to be unreachable");
+ }
+ test_udp_server (transport->xp_port);
+
+ int status;
+ xwaitpid (pid, &status, 0);
+ TEST_VERIFY (WIFEXITED (status) && WEXITSTATUS (status) == EXIT_MARKER);
+
+ SVC_DESTROY (transport);
+ return 0;
+}
+
+/* The minimum run time is around 17 seconds. */
+#define TIMEOUT 25
+#include <support/test-driver.c>