texlive[58283] Build/source/texk/web2c/lib: Disable commands

[commits+kakuto at tug.org]

Revision: 58283
          http://tug.org/svn/texlive?view=revision&revision=58283
Author:   kakuto
Date:     2021-03-12 00:48:40 +0100 (Fri, 12 Mar 2021)
Log Message:
-----------
Disable commands containing a character '|' for write18 in restricted mode for security.

Modified Paths:
--------------
    trunk/Build/source/texk/web2c/lib/ChangeLog
    trunk/Build/source/texk/web2c/lib/texmfmp.c

Modified: trunk/Build/source/texk/web2c/lib/ChangeLog
===================================================================
--- trunk/Build/source/texk/web2c/lib/ChangeLog	2021-03-11 23:05:10 UTC (rev 58282)
+++ trunk/Build/source/texk/web2c/lib/ChangeLog	2021-03-11 23:48:40 UTC (rev 58283)
@@ -1,3 +1,8 @@
+2021-03-12  Akira Kakuto  <kakuto at w32tex.org>
+
+	* texmfmp.c: Disable commands containing a character '|' for
+	write18 in restricted mode for security.
+
 2021-01-01  Akira Kakuto  <kakuto at w32tex.org>
 
 	* printversion.c: Update copyright year.

Modified: trunk/Build/source/texk/web2c/lib/texmfmp.c
===================================================================
--- trunk/Build/source/texk/web2c/lib/texmfmp.c	2021-03-11 23:05:10 UTC (rev 58282)
+++ trunk/Build/source/texk/web2c/lib/texmfmp.c	2021-03-11 23:48:40 UTC (rev 58283)
@@ -610,8 +610,18 @@
 
   if (allow == 1)
     status = system (cmd);
-  else if (allow == 2)
+  else if (allow == 2) {
+/*
+  command including a character '|' is not allowed in
+  restricted mode for security.
+*/
+    size_t k;
+    for (k = 0; k < strlen (safecmd); k++) {
+      if (safecmd[k] == '|')
+        return 0;
+    }
     status =  system (safecmd);
+  }
 
   /* Not really meaningful, but we have to manage the return value of system. */
   if (status != 0)