- Fix NLnetLabs#782: Segmentation fault in stats.c:404.

Author: wcawijngaards

doc/Changelog

@@ -1,3 +1,6 @@
+30 November 2022: Wouter
+	- Fix #782: Segmentation fault in stats.c:404.
+
 28 November 2022: Wouter
 	- Fix for the ignore of tcp events for closed comm points, preserve
 	  the use after free protection features.

util/tube.c

@@ -45,6 +45,9 @@
 #include "util/netevent.h"
 #include "util/fptr_wlist.h"
 #include "util/ub_event.h"
+#ifdef HAVE_POLL_H
+#include <poll.h>
+#endif
 
 #ifndef USE_WINSOCK
 /* on unix */
@@ -396,20 +399,28 @@ int tube_read_msg(struct tube* tube, uint8_t** buf, uint32_t* len,
 	return 1;
 }
 
-/** perform a select() on the fd */
+/** perform poll() on the fd */
 static int
 pollit(int fd, struct timeval* t)
 {
-	fd_set r;
+	struct pollfd fds;
+	int pret;
+	int msec = -1;
+	memset(&fds, 0, sizeof(fds));
+	fds.fd = fd;
+	fds.events = POLLIN | POLLERR | POLLHUP;
 #ifndef S_SPLINT_S
-	FD_ZERO(&r);
-	FD_SET(FD_SET_T fd, &r);
+	if(t)
+		msec = t->tv_sec*1000 + t->tv_usec/1000;
 #endif
-	if(select(fd+1, &r, NULL, NULL, t) == -1) {
+
+	pret = poll(&fds, 1, msec);
+
+	if(pret == -1)
 		return 0;
-	}
-	errno = 0;
-	return (int)(FD_ISSET(fd, &r));
+	if(pret != 0)
+		return 1;
+	return 0;
 }
 
 int tube_poll(struct tube* tube)
@@ -426,24 +437,27 @@ int tube_wait(struct tube* tube)
 
 int tube_wait_timeout(struct tube* tube, int msec)
 {
-	struct timeval t;
-	int fd = tube->sr;
-	fd_set r;
-	t.tv_sec = msec/1000;
-	t.tv_usec = (msec%1000)*1000;
-#ifndef S_SPLINT_S
-	FD_ZERO(&r);
-	FD_SET(FD_SET_T fd, &r);
-#endif
+	int ret = 0;
+
 	while(1) {
-		if(select(fd+1, &r, NULL, NULL, &t) == -1) {
+		struct pollfd fds;
+		memset(&fds, 0, sizeof(fds));
+
+		fds.fd = tube->sr;
+		fds.events = POLLIN | POLLERR | POLLHUP;
+		ret = poll(&fds, 1, msec);
+
+		if(ret == -1) {
 			if(errno == EAGAIN || errno == EINTR)
 				continue;
 			return -1;
 		}
 		break;
 	}
-	return (int)(FD_ISSET(fd, &r));
+
+	if(ret != 0)
+		return 1;
+	return 0;
 }
 
 int tube_read_fd(struct tube* tube)