Fix CVE-2017-12836:

http://cve.mitre.org/cgi-bin/cvename.cgi?name=2017-12836
https://security-tracker.debian.org/tracker/CVE-2017-12836

Patch adpated from Debian (comments and changelog annotations removed):

https://anonscm.debian.org/cgit/collab-maint/cvs.git/commit/?h=stretch&id=41e077396e35efb6c879951f44c62dd8a1d0f094

From 41e077396e35efb6c879951f44c62dd8a1d0f094 Mon Sep 17 00:00:00 2001
From: mirabilos <m@mirbsd.org>
Date: Sat, 12 Aug 2017 03:17:18 +0200
Subject: Fix CVE-2017-12836 (Closes: #871810) for stretch

---
 debian/changelog |  6 ++++++
 src/rsh-client.c | 10 ++++++++--
 2 files changed, 14 insertions(+), 2 deletions(-)

diff --git a/src/rsh-client.c b/src/rsh-client.c
index fe0cfc4..1fc860d 100644
--- a/src/rsh-client.c
+++ b/src/rsh-client.c
@@ -105,6 +106,9 @@ start_rsh_server (cvsroot_t *root, struct buffer **to_server_p,
 	rsh_argv[i++] = argvport;
     }
 
+    /* Only non-option arguments from here. (CVE-2017-12836) */
+    rsh_argv[i++] = "--";
+
     rsh_argv[i++] = root->hostname;
     rsh_argv[i++] = cvs_server;
     if (readonlyfs)
@@ -189,6 +193,8 @@ start_rsh_server (cvsroot_t *root, struct buffer **to_server_p,
 		*p++ = argvport;
 	}
 
+	*p++ = "--";
+
 	*p++ = root->hostname;
 	*p++ = command;
 	*p++ = NULL;
-- 
cgit v0.12

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<tr><td><span title='2024-03-09 18:55:49 +0100'>2024-03-09</span></td><td><a href='/guix/commit/tests/lint.scm?id=47a0e5d9fb2209a27c2bffa163becbcb3356bf00'>lint: archival: Trigger “Save Code Now” for VCSes other than Git.</a><span class='msg-avail'>...</span></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2024-02-12 12:03:53 +0100'>2024-02-12</span></td><td><a href='/guix/commit/tests/lint.scm?id=29f3089c841f00144f24f5c32296aebf22d752cc'>lint: archival: Check with ‘lookup-directory-by-nar-hash’.</a><span class='msg-avail'>...</span></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2023-09-08 19:12:15 +0200'>2023-09-08</span></td><td><a href='/guix/commit/tests/lint.scm?id=96eda590e1eb288359532d92bbfc4795c60f3df5'>lint: Check that (cc-for-target) and friends are used.</a><span class='msg-avail'>...</span></td><td>Maxime Devos</td></tr>
<tr><td><span title='2023-05-06 17:12:45 +0200'>2023-05-06</span></td><td><a href='/guix/commit/tests/lint.scm?id=71fd35c1d55988c413a37c7d15006b4d38d7dde7'>lint: archival: Warn against non-origin package sources.</a><span class='msg-avail'>...</span></td><td>Ludovic Courtès</td></tr>