From: Baruch Siach Date: Tue, 12 Feb 2019 12:13:04 +0000 (+0200) Subject: openssh: add upstream security fixes X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=7fe3741bc4197f6bff48236f357f5db1269586c7;p=buildroot.git openssh: add upstream security fixes CVE-2019-6109: Due to missing character encoding in the progress display, a malicious server (or Man-in-The-Middle attacker) can employ crafted object names to manipulate the client output, e.g., by using ANSI control codes to hide additional files being transferred. This affects refresh_progress_meter() in progressmeter.c. CVE-2019-6111: Due to the scp implementation being derived from 1983 rcp, the server chooses which files/directories are sent to the client. However, the scp client only performs cursory validation of the object name returned (only directory traversal attacks are prevented). A malicious scp server (or Man-in-The-Middle attacker) can overwrite arbitrary files in the scp client target directory. If recursive operation (-r) is performed, the server can manipulate subdirectories as well (for example, to overwrite the .ssh/authorized_keys file). Signed-off-by: Baruch Siach Signed-off-by: Peter Korsgaard --- diff --git a/package/openssh/0002-upstream-Sanitize-scp-filenames-via-snmprintf.-To-do.patch b/package/openssh/0002-upstream-Sanitize-scp-filenames-via-snmprintf.-To-do.patch new file mode 100644 index 0000000000..e5d137ef11 --- /dev/null +++ b/package/openssh/0002-upstream-Sanitize-scp-filenames-via-snmprintf.-To-do.patch @@ -0,0 +1,275 @@ +From 5979bdfeca813dd7e997a1edb0f928d77ce70304 Mon Sep 17 00:00:00 2001 +From: "dtucker@openbsd.org" +Date: Wed, 23 Jan 2019 08:01:46 +0000 +Subject: [PATCH] upstream: Sanitize scp filenames via snmprintf. To do this we + move + +the progressmeter formatting outside of signal handler context and have the +atomicio callback called for EINTR too. bz#2434 with contributions from djm +and jjelen at redhat.com, ok djm@ + +OpenBSD-Commit-ID: 1af61c1f70e4f3bd8ab140b9f1fa699481db57d8 +Signed-off-by: Baruch Siach +--- +Upstream status (openssh-portable): backported from commit 8976f1c4b27 +--- + atomicio.c | 20 ++++++++++++++----- + progressmeter.c | 53 ++++++++++++++++++++++--------------------------- + progressmeter.h | 3 ++- + scp.c | 1 + + sftp-client.c | 16 ++++++++------- + 5 files changed, 51 insertions(+), 42 deletions(-) + +diff --git a/atomicio.c b/atomicio.c +index f854a06f5f50..d91bd7621c12 100644 +--- a/atomicio.c ++++ b/atomicio.c +@@ -1,4 +1,4 @@ +-/* $OpenBSD: atomicio.c,v 1.28 2016/07/27 23:18:12 djm Exp $ */ ++/* $OpenBSD: atomicio.c,v 1.29 2019/01/23 08:01:46 dtucker Exp $ */ + /* + * Copyright (c) 2006 Damien Miller. All rights reserved. + * Copyright (c) 2005 Anil Madhavapeddy. All rights reserved. +@@ -65,9 +65,14 @@ atomicio6(ssize_t (*f) (int, void *, size_t), int fd, void *_s, size_t n, + res = (f) (fd, s + pos, n - pos); + switch (res) { + case -1: +- if (errno == EINTR) ++ if (errno == EINTR) { ++ /* possible SIGALARM, update callback */ ++ if (cb != NULL && cb(cb_arg, 0) == -1) { ++ errno = EINTR; ++ return pos; ++ } + continue; +- if (errno == EAGAIN || errno == EWOULDBLOCK) { ++ } else if (errno == EAGAIN || errno == EWOULDBLOCK) { + #ifndef BROKEN_READ_COMPARISON + (void)poll(&pfd, 1, -1); + #endif +@@ -122,9 +127,14 @@ atomiciov6(ssize_t (*f) (int, const struct iovec *, int), int fd, + res = (f) (fd, iov, iovcnt); + switch (res) { + case -1: +- if (errno == EINTR) ++ if (errno == EINTR) { ++ /* possible SIGALARM, update callback */ ++ if (cb != NULL && cb(cb_arg, 0) == -1) { ++ errno = EINTR; ++ return pos; ++ } + continue; +- if (errno == EAGAIN || errno == EWOULDBLOCK) { ++ } else if (errno == EAGAIN || errno == EWOULDBLOCK) { + #ifndef BROKEN_READV_COMPARISON + (void)poll(&pfd, 1, -1); + #endif +diff --git a/progressmeter.c b/progressmeter.c +index fe9bf52e4c90..add462dde500 100644 +--- a/progressmeter.c ++++ b/progressmeter.c +@@ -1,4 +1,4 @@ +-/* $OpenBSD: progressmeter.c,v 1.45 2016/06/30 05:17:05 dtucker Exp $ */ ++/* $OpenBSD: progressmeter.c,v 1.46 2019/01/23 08:01:46 dtucker Exp $ */ + /* + * Copyright (c) 2003 Nils Nordman. All rights reserved. + * +@@ -31,6 +31,7 @@ + + #include + #include ++#include + #include + #include + #include +@@ -39,6 +40,7 @@ + #include "progressmeter.h" + #include "atomicio.h" + #include "misc.h" ++#include "utf8.h" + + #define DEFAULT_WINSIZE 80 + #define MAX_WINSIZE 512 +@@ -61,7 +63,7 @@ static void setscreensize(void); + void refresh_progress_meter(void); + + /* signal handler for updating the progress meter */ +-static void update_progress_meter(int); ++static void sig_alarm(int); + + static double start; /* start progress */ + static double last_update; /* last progress update */ +@@ -74,6 +76,7 @@ static long stalled; /* how long we have been stalled */ + static int bytes_per_second; /* current speed in bytes per second */ + static int win_size; /* terminal window size */ + static volatile sig_atomic_t win_resized; /* for window resizing */ ++static volatile sig_atomic_t alarm_fired; + + /* units for format_size */ + static const char unit[] = " KMGT"; +@@ -126,9 +129,17 @@ refresh_progress_meter(void) + off_t bytes_left; + int cur_speed; + int hours, minutes, seconds; +- int i, len; + int file_len; + ++ if ((!alarm_fired && !win_resized) || !can_output()) ++ return; ++ alarm_fired = 0; ++ ++ if (win_resized) { ++ setscreensize(); ++ win_resized = 0; ++ } ++ + transferred = *counter - (cur_pos ? cur_pos : start_pos); + cur_pos = *counter; + now = monotime_double(); +@@ -158,16 +169,11 @@ refresh_progress_meter(void) + + /* filename */ + buf[0] = '\0'; +- file_len = win_size - 35; ++ file_len = win_size - 36; + if (file_len > 0) { +- len = snprintf(buf, file_len + 1, "\r%s", file); +- if (len < 0) +- len = 0; +- if (len >= file_len + 1) +- len = file_len; +- for (i = len; i < file_len; i++) +- buf[i] = ' '; +- buf[file_len] = '\0'; ++ buf[0] = '\r'; ++ snmprintf(buf+1, sizeof(buf)-1 , &file_len, "%*s", ++ file_len * -1, file); + } + + /* percent of transfer done */ +@@ -228,22 +234,11 @@ refresh_progress_meter(void) + + /*ARGSUSED*/ + static void +-update_progress_meter(int ignore) ++sig_alarm(int ignore) + { +- int save_errno; +- +- save_errno = errno; +- +- if (win_resized) { +- setscreensize(); +- win_resized = 0; +- } +- if (can_output()) +- refresh_progress_meter(); +- +- signal(SIGALRM, update_progress_meter); ++ signal(SIGALRM, sig_alarm); ++ alarm_fired = 1; + alarm(UPDATE_INTERVAL); +- errno = save_errno; + } + + void +@@ -259,10 +254,9 @@ start_progress_meter(const char *f, off_t filesize, off_t *ctr) + bytes_per_second = 0; + + setscreensize(); +- if (can_output()) +- refresh_progress_meter(); ++ refresh_progress_meter(); + +- signal(SIGALRM, update_progress_meter); ++ signal(SIGALRM, sig_alarm); + signal(SIGWINCH, sig_winch); + alarm(UPDATE_INTERVAL); + } +@@ -286,6 +280,7 @@ stop_progress_meter(void) + static void + sig_winch(int sig) + { ++ signal(SIGWINCH, sig_winch); + win_resized = 1; + } + +diff --git a/progressmeter.h b/progressmeter.h +index bf179dca6518..8f6678060195 100644 +--- a/progressmeter.h ++++ b/progressmeter.h +@@ -1,4 +1,4 @@ +-/* $OpenBSD: progressmeter.h,v 1.3 2015/01/14 13:54:13 djm Exp $ */ ++/* $OpenBSD: progressmeter.h,v 1.4 2019/01/23 08:01:46 dtucker Exp $ */ + /* + * Copyright (c) 2002 Nils Nordman. All rights reserved. + * +@@ -24,4 +24,5 @@ + */ + + void start_progress_meter(const char *, off_t, off_t *); ++void refresh_progress_meter(void); + void stop_progress_meter(void); +diff --git a/scp.c b/scp.c +index 4f3fdcd3db89..4a342a63873c 100644 +--- a/scp.c ++++ b/scp.c +@@ -585,6 +585,7 @@ scpio(void *_cnt, size_t s) + off_t *cnt = (off_t *)_cnt; + + *cnt += s; ++ refresh_progress_meter(); + if (limit_kbps > 0) + bandwidth_limit(&bwlimit, s); + return 0; +diff --git a/sftp-client.c b/sftp-client.c +index 4986d6d8d291..2bc698f868bc 100644 +--- a/sftp-client.c ++++ b/sftp-client.c +@@ -101,7 +101,9 @@ sftpio(void *_bwlimit, size_t amount) + { + struct bwlimit *bwlimit = (struct bwlimit *)_bwlimit; + +- bandwidth_limit(bwlimit, amount); ++ refresh_progress_meter(); ++ if (bwlimit != NULL) ++ bandwidth_limit(bwlimit, amount); + return 0; + } + +@@ -121,8 +123,8 @@ send_msg(struct sftp_conn *conn, struct sshbuf *m) + iov[1].iov_base = (u_char *)sshbuf_ptr(m); + iov[1].iov_len = sshbuf_len(m); + +- if (atomiciov6(writev, conn->fd_out, iov, 2, +- conn->limit_kbps > 0 ? sftpio : NULL, &conn->bwlimit_out) != ++ if (atomiciov6(writev, conn->fd_out, iov, 2, sftpio, ++ conn->limit_kbps > 0 ? &conn->bwlimit_out : NULL) != + sshbuf_len(m) + sizeof(mlen)) + fatal("Couldn't send packet: %s", strerror(errno)); + +@@ -138,8 +140,8 @@ get_msg_extended(struct sftp_conn *conn, struct sshbuf *m, int initial) + + if ((r = sshbuf_reserve(m, 4, &p)) != 0) + fatal("%s: buffer error: %s", __func__, ssh_err(r)); +- if (atomicio6(read, conn->fd_in, p, 4, +- conn->limit_kbps > 0 ? sftpio : NULL, &conn->bwlimit_in) != 4) { ++ if (atomicio6(read, conn->fd_in, p, 4, sftpio, ++ conn->limit_kbps > 0 ? &conn->bwlimit_in : NULL) != 4) { + if (errno == EPIPE || errno == ECONNRESET) + fatal("Connection closed"); + else +@@ -157,8 +159,8 @@ get_msg_extended(struct sftp_conn *conn, struct sshbuf *m, int initial) + + if ((r = sshbuf_reserve(m, msg_len, &p)) != 0) + fatal("%s: buffer error: %s", __func__, ssh_err(r)); +- if (atomicio6(read, conn->fd_in, p, msg_len, +- conn->limit_kbps > 0 ? sftpio : NULL, &conn->bwlimit_in) ++ if (atomicio6(read, conn->fd_in, p, msg_len, sftpio, ++ conn->limit_kbps > 0 ? &conn->bwlimit_in : NULL) + != msg_len) { + if (errno == EPIPE) + fatal("Connection closed"); +-- +2.20.1 + diff --git a/package/openssh/0003-upstream-check-in-scp-client-that-filenames-sent-dur.patch b/package/openssh/0003-upstream-check-in-scp-client-that-filenames-sent-dur.patch new file mode 100644 index 0000000000..98ce5cd876 --- /dev/null +++ b/package/openssh/0003-upstream-check-in-scp-client-that-filenames-sent-dur.patch @@ -0,0 +1,186 @@ +From f853123eda6b279a87be48e18bbea8dec82a94f2 Mon Sep 17 00:00:00 2001 +From: "djm@openbsd.org" +Date: Sat, 26 Jan 2019 22:41:28 +0000 +Subject: [PATCH] upstream: check in scp client that filenames sent during + +remote->local directory copies satisfy the wildcard specified by the user. + +This checking provides some protection against a malicious server +sending unexpected filenames, but it comes at a risk of rejecting wanted +files due to differences between client and server wildcard expansion rules. + +For this reason, this also adds a new -T flag to disable the check. + +reported by Harry Sintonen +fix approach suggested by markus@; +has been in snaps for ~1wk courtesy deraadt@ + +OpenBSD-Commit-ID: 00f44b50d2be8e321973f3c6d014260f8f7a8eda +Signed-off-by: Baruch Siach +--- +Upstream status (openssh-portable): backported from commit 8976f1c4b2 +--- + scp.1 | 12 +++++++++++- + scp.c | 37 +++++++++++++++++++++++++++++-------- + 2 files changed, 40 insertions(+), 9 deletions(-) + +diff --git a/scp.1 b/scp.1 +index 0e5cc1b2d675..397e7709195a 100644 +--- a/scp.1 ++++ b/scp.1 +@@ -18,7 +18,7 @@ + .Nd secure copy (remote file copy program) + .Sh SYNOPSIS + .Nm scp +-.Op Fl 346BCpqrv ++.Op Fl 346BCpqrTv + .Op Fl c Ar cipher + .Op Fl F Ar ssh_config + .Op Fl i Ar identity_file +@@ -208,6 +208,16 @@ to use for the encrypted connection. + The program must understand + .Xr ssh 1 + options. ++.It Fl T ++Disable strict filename checking. ++By default when copying files from a remote host to a local directory ++.Nm ++checks that the received filenames match those requested on the command-line ++to prevent the remote end from sending unexpected or unwanted files. ++Because of differences in how various operating systems and shells interpret ++filename wildcards, these checks may cause wanted files to be rejected. ++This option disables these checks at the expense of fully trusting that ++the server will not send unexpected filenames. + .It Fl v + Verbose mode. + Causes +diff --git a/scp.c b/scp.c +index 4a342a63873c..7b0a08efb274 100644 +--- a/scp.c ++++ b/scp.c +@@ -94,6 +94,7 @@ + #include + #include + #include ++#include + #include + #include + #include +@@ -375,14 +376,14 @@ void verifydir(char *); + struct passwd *pwd; + uid_t userid; + int errs, remin, remout; +-int pflag, iamremote, iamrecursive, targetshouldbedirectory; ++int Tflag, pflag, iamremote, iamrecursive, targetshouldbedirectory; + + #define CMDNEEDS 64 + char cmd[CMDNEEDS]; /* must hold "rcp -r -p -d\0" */ + + int response(void); + void rsource(char *, struct stat *); +-void sink(int, char *[]); ++void sink(int, char *[], const char *); + void source(int, char *[]); + void tolocal(int, char *[]); + void toremote(int, char *[]); +@@ -421,8 +422,9 @@ main(int argc, char **argv) + addargs(&args, "-oRemoteCommand=none"); + addargs(&args, "-oRequestTTY=no"); + +- fflag = tflag = 0; +- while ((ch = getopt(argc, argv, "dfl:prtvBCc:i:P:q12346S:o:F:")) != -1) ++ fflag = Tflag = tflag = 0; ++ while ((ch = getopt(argc, argv, ++ "dfl:prtTvBCc:i:P:q12346S:o:F:")) != -1) { + switch (ch) { + /* User-visible flags. */ + case '1': +@@ -501,9 +503,13 @@ main(int argc, char **argv) + setmode(0, O_BINARY); + #endif + break; ++ case 'T': ++ Tflag = 1; ++ break; + default: + usage(); + } ++ } + argc -= optind; + argv += optind; + +@@ -534,7 +540,7 @@ main(int argc, char **argv) + } + if (tflag) { + /* Receive data. */ +- sink(argc, argv); ++ sink(argc, argv, NULL); + exit(errs != 0); + } + if (argc < 2) +@@ -792,7 +798,7 @@ tolocal(int argc, char **argv) + continue; + } + free(bp); +- sink(1, argv + argc - 1); ++ sink(1, argv + argc - 1, src); + (void) close(remin); + remin = remout = -1; + } +@@ -968,7 +974,7 @@ rsource(char *name, struct stat *statp) + (sizeof(type) != 4 && sizeof(type) != 8)) + + void +-sink(int argc, char **argv) ++sink(int argc, char **argv, const char *src) + { + static BUF buffer; + struct stat stb; +@@ -984,6 +990,7 @@ sink(int argc, char **argv) + unsigned long long ull; + int setimes, targisdir, wrerrno = 0; + char ch, *cp, *np, *targ, *why, *vect[1], buf[2048], visbuf[2048]; ++ char *src_copy = NULL, *restrict_pattern = NULL; + struct timeval tv[2]; + + #define atime tv[0] +@@ -1008,6 +1015,17 @@ sink(int argc, char **argv) + (void) atomicio(vwrite, remout, "", 1); + if (stat(targ, &stb) == 0 && S_ISDIR(stb.st_mode)) + targisdir = 1; ++ if (src != NULL && !iamrecursive && !Tflag) { ++ /* ++ * Prepare to try to restrict incoming filenames to match ++ * the requested destination file glob. ++ */ ++ if ((src_copy = strdup(src)) == NULL) ++ fatal("strdup failed"); ++ if ((restrict_pattern = strrchr(src_copy, '/')) != NULL) { ++ *restrict_pattern++ = '\0'; ++ } ++ } + for (first = 1;; first = 0) { + cp = buf; + if (atomicio(read, remin, cp, 1) != 1) +@@ -1112,6 +1130,9 @@ sink(int argc, char **argv) + run_err("error: unexpected filename: %s", cp); + exit(1); + } ++ if (restrict_pattern != NULL && ++ fnmatch(restrict_pattern, cp, 0) != 0) ++ SCREWUP("filename does not match request"); + if (targisdir) { + static char *namebuf; + static size_t cursize; +@@ -1149,7 +1170,7 @@ sink(int argc, char **argv) + goto bad; + } + vect[0] = xstrdup(np); +- sink(1, vect); ++ sink(1, vect, src); + if (setimes) { + setimes = 0; + if (utimes(vect[0], tv) < 0) +-- +2.20.1 +