File ppp-2.4.3-fork-fix.diff of Package ppp

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File ppp-2.4.3-fork-fix.diff of Package ppp (Revision 78337385bfc2deeb3e6cfb5f0b029570)

Currently displaying revision 78337385bfc2deeb3e6cfb5f0b029570 , Show latest

--- pppd/main.c
+++ pppd/main.c
@@ -1540,14 +1540,6 @@
 	int fd, pipefd[2];
 	char buf[1];
 
-	/* make sure fds 0, 1, 2 are occupied (probably not necessary) */
-	while ((fd = dup(fd_devnull)) >= 0) {
-		if (fd > 2) {
-			close(fd);
-			break;
-		}
-	}
-
 	if (pipe(pipefd) == -1)
 		pipefd[0] = pipefd[1] = -1;
 	pid = fork();
@@ -1570,25 +1562,31 @@
 	tdb_close(pppdb);
 #endif
 
-	/* make sure infd, outfd and errfd won't get tromped on below */
-	if (infd == 1 || infd == 2)
-		infd = dup(infd);
-	if (outfd == 0 || outfd == 2)
-		outfd = dup(outfd);
-	if (errfd == 0 || errfd == 1)
-		errfd = dup(errfd);
-
+        /* make sure fds 0, 1, 2 are occupied, so the duplicated  fds always > 2 */
+        while ((fd = dup(fd_devnull)) >= 0) {
+                if (fd > 2) {
+                        close(fd);
+                        break;
+                }
+        }
+
+        /* always copy fd's to avoid to use a already closed fd later */
+        {
+                int     fdi = infd, fdo = outfd;
+ 
+                infd = dup(infd);
+                outfd = dup(outfd);
+                if (errfd >= 0) {
+                        fd = errfd;
+                        errfd = dup(errfd);
+                        close(fd);
+                }
+                close(fdi);
+                close(fdo);
+        }
 	closelog();
 
-	/* dup the in, out, err fds to 0, 1, 2 */
-	if (infd != 0)
-		dup2(infd, 0);
-	if (outfd != 1)
-		dup2(outfd, 1);
-	if (errfd != 2)
-		dup2(errfd, 2);
-
-	if (log_to_fd > 2)
+	if (log_to_fd > 0)
 		close(log_to_fd);
 	if (the_channel->close)
 		(*the_channel->close)();
@@ -1596,12 +1594,18 @@
 		close(devfd);	/* some plugins don't have a close function */
 	close(fd_ppp);
 	close(fd_devnull);
-	if (infd != 0)
-		close(infd);
-	if (outfd != 1)
-		close(outfd);
-	if (errfd != 2)
-		close(errfd);
+
+	close(0);
+        dup2(infd, 0);
+        close(infd);
+        close(1);
+        dup2(outfd, 1);
+        close(outfd);
+        if (errfd >= 0) {
+                close(2);
+                dup2(errfd, 2);
+ 		close(errfd);
+	}
 
 	notify(fork_notifier, 0);
 	close(pipefd[0]);

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File ppp-2.4.3-fork-fix.diff of Package ppp (Revision 78337385bfc2deeb3e6cfb5f0b029570)

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