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authorDenys Vlasenko <vda.linux@googlemail.com>2011-09-11 14:48:21 (GMT)
committer Denys Vlasenko <vda.linux@googlemail.com>2011-09-11 14:48:21 (GMT)
commit223b9417b3789e60f3a91510661b00a92c0db027 (patch)
tree2616985d865a3ddbc8653db23f1b106e9e39a039
parentd2fe2ba08dd84cd7e94d1ae3e2e9c12ca2b4d561 (diff)
downloadbusybox-223b9417b3789e60f3a91510661b00a92c0db027.tar.gz
busybox-223b9417b3789e60f3a91510661b00a92c0db027.tar.bz2
inetd: close new udp fd in "udp nowait" case
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
-rw-r--r--networking/inetd.c66
1 files changed, 55 insertions, 11 deletions
diff --git a/networking/inetd.c b/networking/inetd.c
index 873fd95..fc6847b 100644
--- a/networking/inetd.c
+++ b/networking/inetd.c
@@ -357,10 +357,26 @@ struct BUG_G_too_big {
config_filename = "/etc/inetd.conf"; \
} while (0)
+#if 1
+# define dbg(...) ((void)0)
+#else
+# define dbg(...) \
+do { \
+ int dbg_fd = open("inetd_debug.log", O_WRONLY | O_CREAT | O_APPEND, 0666); \
+ if (dbg_fd >= 0) { \
+ fdprintf(dbg_fd, "%d: ", getpid()); \
+ fdprintf(dbg_fd, __VA_ARGS__); \
+ close(dbg_fd); \
+ } \
+} while (0)
+#endif
+
static void maybe_close(int fd)
{
- if (fd >= 0)
+ if (fd >= 0) {
close(fd);
+ dbg("closed fd:%d\n", fd);
+ }
}
// TODO: move to libbb?
@@ -464,7 +480,9 @@ static void remove_fd_from_set(int fd)
{
if (fd >= 0) {
FD_CLR(fd, &allsock);
+ dbg("stopped listening on fd:%d\n", fd);
maxsock = -1;
+ dbg("maxsock:%d\n", maxsock);
}
}
@@ -472,8 +490,10 @@ static void add_fd_to_set(int fd)
{
if (fd >= 0) {
FD_SET(fd, &allsock);
+ dbg("started listening on fd:%d\n", fd);
if (maxsock >= 0 && fd > maxsock) {
prev_maxsock = maxsock = fd;
+ dbg("maxsock:%d\n", maxsock);
if ((rlim_t)fd > rlim_ofile_cur - FD_MARGIN)
bump_nofile();
}
@@ -492,6 +512,7 @@ static void recalculate_maxsock(void)
maxsock = fd;
fd++;
}
+ dbg("recalculated maxsock:%d\n", maxsock);
prev_maxsock = maxsock;
if ((rlim_t)maxsock > rlim_ofile_cur - FD_MARGIN)
bump_nofile();
@@ -549,8 +570,13 @@ static void prepare_socket_fd(servtab_t *sep)
rearm_alarm();
return;
}
- if (sep->se_socktype == SOCK_STREAM)
+
+ if (sep->se_socktype == SOCK_STREAM) {
listen(fd, global_queuelen);
+ dbg("new sep->se_fd:%d (stream)\n", fd);
+ } else {
+ dbg("new sep->se_fd:%d (!stream)\n", fd);
+ }
add_fd_to_set(fd);
sep->se_fd = fd;
@@ -1012,7 +1038,7 @@ static void reread_config_file(int sig UNUSED_PARAM)
* new config file doesnt have them. */
block_CHLD_HUP_ALRM(&omask);
sepp = &serv_list;
- while ((sep = *sepp)) {
+ while ((sep = *sepp) != NULL) {
if (sep->se_checked) {
sepp = &sep->se_next;
continue;
@@ -1206,11 +1232,13 @@ int inetd_main(int argc UNUSED_PARAM, char **argv)
}
continue;
}
+ dbg("ready_fd_cnt:%d\n", ready_fd_cnt);
for (sep = serv_list; ready_fd_cnt && sep; sep = sep->se_next) {
if (sep->se_fd == -1 || !FD_ISSET(sep->se_fd, &readable))
continue;
+ dbg("ready fd:%d\n", sep->se_fd);
ready_fd_cnt--;
ctrl = sep->se_fd;
accepted_fd = -1;
@@ -1218,6 +1246,7 @@ int inetd_main(int argc UNUSED_PARAM, char **argv)
if (!sep->se_wait) {
if (sep->se_socktype == SOCK_STREAM) {
ctrl = accepted_fd = accept(sep->se_fd, NULL, NULL);
+ dbg("accepted_fd:%d\n", accepted_fd);
if (ctrl < 0) {
if (errno != EINTR)
bb_perror_msg("accept (for %s)", sep->se_service);
@@ -1238,19 +1267,22 @@ int inetd_main(int argc UNUSED_PARAM, char **argv)
* (can create many copies of same child, etc).
* Parent must create and use new socket instead. */
new_udp_fd = socket(sep->se_family, SOCK_DGRAM, 0);
+ dbg("new_udp_fd:%d\n", new_udp_fd);
if (new_udp_fd < 0) { /* error: eat packet, forget about it */
udp_err:
recv(sep->se_fd, line, LINE_SIZE, MSG_DONTWAIT);
continue;
}
setsockopt_reuseaddr(new_udp_fd);
- /* TODO: better do bind after vfork in parent,
+ /* TODO: better do bind after fork in parent,
* so that we don't have two wildcard bound sockets
* even for a brief moment? */
if (bind(new_udp_fd, &sep->se_lsa->u.sa, sep->se_lsa->len) < 0) {
+ dbg("bind(new_udp_fd) failed\n");
close(new_udp_fd);
goto udp_err;
}
+ dbg("bind(new_udp_fd) succeeded\n");
}
}
@@ -1278,6 +1310,7 @@ int inetd_main(int argc UNUSED_PARAM, char **argv)
sep->se_count = 0;
rearm_alarm(); /* will revive it in RETRYTIME sec */
restore_sigmask(&omask);
+ maybe_close(new_udp_fd);
maybe_close(accepted_fd);
continue; /* -> check next fd in fd set */
}
@@ -1298,17 +1331,18 @@ int inetd_main(int argc UNUSED_PARAM, char **argv)
bb_perror_msg("vfork"+1);
sleep(1);
restore_sigmask(&omask);
+ maybe_close(new_udp_fd);
maybe_close(accepted_fd);
continue; /* -> check next fd in fd set */
}
if (pid == 0)
pid--; /* -1: "we did fork and we are child" */
}
- /* if pid == 0 here, we never forked */
+ /* if pid == 0 here, we didn't fork */
if (pid > 0) { /* parent */
if (sep->se_wait) {
- /* tcp wait: we passed listening socket to child,
+ /* wait: we passed socket to child,
* will wait for child to terminate */
sep->se_wait = pid;
remove_fd_from_set(sep->se_fd);
@@ -1317,17 +1351,19 @@ int inetd_main(int argc UNUSED_PARAM, char **argv)
/* udp nowait: child connected the socket,
* we created and will use new, unconnected one */
xmove_fd(new_udp_fd, sep->se_fd);
+ dbg("moved new_udp_fd:%d to sep->se_fd:%d\n", new_udp_fd, sep->se_fd);
}
restore_sigmask(&omask);
maybe_close(accepted_fd);
continue; /* -> check next fd in fd set */
}
- /* we are either child or didn't vfork at all */
+ /* we are either child or didn't fork at all */
#ifdef INETD_BUILTINS_ENABLED
if (sep->se_builtin) {
- if (pid) { /* "pid" is -1: we did vfork */
+ if (pid) { /* "pid" is -1: we did fork */
close(sep->se_fd); /* listening socket */
+ dbg("closed sep->se_fd:%d\n", sep->se_fd);
logmode = LOGMODE_NONE; /* make xwrite etc silent */
}
restore_sigmask(&omask);
@@ -1335,7 +1371,7 @@ int inetd_main(int argc UNUSED_PARAM, char **argv)
sep->se_builtin->bi_stream_fn(ctrl, sep);
else
sep->se_builtin->bi_dgram_fn(ctrl, sep);
- if (pid) /* we did vfork */
+ if (pid) /* we did fork */
_exit(EXIT_FAILURE);
maybe_close(accepted_fd);
continue; /* -> check next fd in fd set */
@@ -1345,9 +1381,14 @@ int inetd_main(int argc UNUSED_PARAM, char **argv)
setsid();
/* "nowait" udp */
if (new_udp_fd >= 0) {
- len_and_sockaddr *lsa = xzalloc_lsa(sep->se_family);
+ len_and_sockaddr *lsa;
+ int r;
+
+ close(new_udp_fd);
+ dbg("closed new_udp_fd:%d\n", new_udp_fd);
+ lsa = xzalloc_lsa(sep->se_family);
/* peek at the packet and remember peer addr */
- int r = recvfrom(ctrl, NULL, 0, MSG_PEEK|MSG_DONTWAIT,
+ r = recvfrom(ctrl, NULL, 0, MSG_PEEK|MSG_DONTWAIT,
&lsa->u.sa, &lsa->len);
if (r < 0)
goto do_exit1;
@@ -1355,6 +1396,7 @@ int inetd_main(int argc UNUSED_PARAM, char **argv)
* only packets from this peer will be recv'ed,
* and bare write()/send() will work on it */
connect(ctrl, &lsa->u.sa, lsa->len);
+ dbg("connected ctrl:%d to remote peer\n", ctrl);
free(lsa);
}
/* prepare env and exec program */
@@ -1391,6 +1433,7 @@ int inetd_main(int argc UNUSED_PARAM, char **argv)
*/
xmove_fd(ctrl, STDIN_FILENO);
xdup2(STDIN_FILENO, STDOUT_FILENO);
+ dbg("moved ctrl:%d to fd 0,1[,2]\n", ctrl);
/* manpages of inetd I managed to find either say
* that stderr is also redirected to the network,
* or do not talk about redirection at all (!) */
@@ -1403,6 +1446,7 @@ int inetd_main(int argc UNUSED_PARAM, char **argv)
maybe_close(sep2->se_fd);
sigaction_set(SIGPIPE, &saved_pipe_handler);
restore_sigmask(&omask);
+ dbg("execing:'%s'\n", sep->se_program);
BB_EXECVP(sep->se_program, sep->se_argv);
bb_perror_msg("can't execute '%s'", sep->se_program);
do_exit1: