From a1d29cc36a5e6eeabc935065a8780e1ba5b67014 Mon Sep 17 00:00:00 2001 From: "deraadt@openbsd.org" Date: Wed, 15 May 2019 04:43:31 +0000 Subject: upstream: When doing the fork+exec'ing for ssh-keysign, rearrange the socket into fd3, so as to not mistakenly leak other fd forward accidentally. ok djm OpenBSD-Commit-ID: 24cc753f5aa2c6a7d0fbf62766adbc75cd785296 --- sshconnect2.c | 16 +++++++++------- 1 file changed, 9 insertions(+), 7 deletions(-) (limited to 'sshconnect2.c') diff --git a/sshconnect2.c b/sshconnect2.c index dffee90b1..d2b5d4c04 100644 --- a/sshconnect2.c +++ b/sshconnect2.c @@ -1,4 +1,4 @@ -/* $OpenBSD: sshconnect2.c,v 1.303 2019/02/12 23:53:10 djm Exp $ */ +/* $OpenBSD: sshconnect2.c,v 1.304 2019/05/15 04:43:31 deraadt Exp $ */ /* * Copyright (c) 2000 Markus Friedl. All rights reserved. * Copyright (c) 2008 Damien Miller. All rights reserved. @@ -1833,7 +1833,7 @@ ssh_keysign(struct ssh *ssh, struct sshkey *key, u_char **sigp, size_t *lenp, struct sshbuf *b; struct stat st; pid_t pid; - int i, r, to[2], from[2], status; + int r, to[2], from[2], status; int sock = ssh_packet_get_connection_in(ssh); u_char rversion = 0, version = 2; void (*osigchld)(int); @@ -1863,8 +1863,6 @@ ssh_keysign(struct ssh *ssh, struct sshkey *key, u_char **sigp, size_t *lenp, } osigchld = signal(SIGCHLD, SIG_DFL); if (pid == 0) { - /* keep the socket on exec */ - fcntl(sock, F_SETFD, 0); close(from[0]); if (dup2(from[1], STDOUT_FILENO) < 0) fatal("%s: dup2: %s", __func__, strerror(errno)); @@ -1873,10 +1871,13 @@ ssh_keysign(struct ssh *ssh, struct sshkey *key, u_char **sigp, size_t *lenp, fatal("%s: dup2: %s", __func__, strerror(errno)); close(from[1]); close(to[0]); - /* Close everything but stdio and the socket */ - for (i = STDERR_FILENO + 1; i < sock; i++) - close(i); + + if (dup2(sock, STDERR_FILENO + 1) < 0) + fatal("%s: dup2: %s", __func__, strerror(errno)); + sock = STDERR_FILENO + 1; + fcntl(sock, F_SETFD, 0); /* keep the socket on exec */ closefrom(sock + 1); + debug3("%s: [child] pid=%ld, exec %s", __func__, (long)getpid(), _PATH_SSH_KEY_SIGN); execl(_PATH_SSH_KEY_SIGN, _PATH_SSH_KEY_SIGN, (char *)NULL); @@ -1885,6 +1886,7 @@ ssh_keysign(struct ssh *ssh, struct sshkey *key, u_char **sigp, size_t *lenp, } close(from[1]); close(to[0]); + sock = STDIN_FILENO + 1; if ((b = sshbuf_new()) == NULL) fatal("%s: sshbuf_new failed", __func__); -- cgit v1.2.3