[pl/f17] Fix CVE-2012-6090

[Petr Pisar]

commit 8e4707fdb925de7b6236b68a0b1fcf7f83545c05
Author: Petr Písař <ppisar at redhat.com>
Date:   Fri Jan 4 12:53:27 2013 +0100

    Fix CVE-2012-6090

 pl-6.0.2-CVE-2012-6090.patch |  112 ++++++++++++++++++++++++++++++++++++++++++
 pl.spec                      |    5 ++
 2 files changed, 117 insertions(+), 0 deletions(-)
---
diff --git a/pl-6.0.2-CVE-2012-6090.patch b/pl-6.0.2-CVE-2012-6090.patch
new file mode 100644
index 0000000..bb6fe94
--- /dev/null
+++ b/pl-6.0.2-CVE-2012-6090.patch
@@ -0,0 +1,112 @@
+From b2c88972e7515ada025e97e7d3ce3e34f81cf33e Mon Sep 17 00:00:00 2001
+From: Jan Wielemaker <J.Wielemaker at cs.vu.nl>
+Date: Sun, 16 Dec 2012 17:29:37 +0100
+Subject: [PATCH] SECURITY: Possible buffer overflows when expanding
+ file-names with long paths.  Affects expand_file_name/2.
+
+Can lead to crashes (DoS attacks) and possibly execution of arbitrary
+code if an attacker can control the names of the files searched for,
+e.g., if expand_file_name/2 is used in a directory to which an attacker
+can upload files for which he can control the name.
+---
+ src/os/pl-glob.c | 46 ++++++++++++++++++++++++++++------------------
+ 1 file changed, 28 insertions(+), 18 deletions(-)
+
+diff --git a/src/os/pl-glob.c b/src/os/pl-glob.c
+index 46ddf5b..0b1baeb 100644
+--- a/src/os/pl-glob.c
++++ b/src/os/pl-glob.c
+@@ -424,6 +424,7 @@ expand(const char *pattern, GlobInfo info)
+   compiled_pattern cbuf;
+   char prefix[MAXPATHLEN];		/* before first pattern */
+   char patbuf[MAXPATHLEN];		/* pattern buffer */
++  size_t prefix_len;
+   int end, dot;
+ 
+   initBuffer(&info->files);
+@@ -442,20 +443,25 @@ expand(const char *pattern, GlobInfo info)
+       switch( (c=*s++) )
+       { case EOS:
+ 	  if ( s > pat )		/* something left and expanded */
+-	  { un_escape(prefix, pat, s);
++	  { size_t prefix_len;
++
++	    un_escape(prefix, pat, s);
++	    prefix_len = strlen(prefix);
+ 
+ 	    end = info->end;
+ 	    for( ; info->start < end; info->start++ )
+ 	    { char path[MAXPATHLEN];
+-	      size_t plen;
+-
+-	      strcpy(path, expand_entry(info, info->start));
+-	      plen = strlen(path);
+-	      if ( prefix[0] && plen > 0 && path[plen-1] != '/' )
+-		path[plen++] = '/';
+-	      strcpy(&path[plen], prefix);
+-	      if ( end == 1 || AccessFile(path, ACCESS_EXIST) )
+-		add_path(path, info);
++	      const char *entry = expand_entry(info, info->start);
++	      size_t plen = strlen(entry);
++
++	      if ( plen+prefix_len+2 <= MAXPATHLEN )
++	      { strcpy(path, entry);
++		if ( prefix[0] && plen > 0 && path[plen-1] != '/' )
++		  path[plen++] = '/';
++		strcpy(&path[plen], prefix);
++		if ( end == 1 || AccessFile(path, ACCESS_EXIST) )
++		  add_path(path, info);
++	      }
+ 	    }
+ 	  }
+ 	  succeed;
+@@ -490,8 +496,9 @@ expand(const char *pattern, GlobInfo info)
+ */
+     un_escape(prefix, pat, head);
+     un_escape(patbuf, head, tail);
++    prefix_len = strlen(prefix);
+ 
+-    if ( !compilePattern(patbuf, &cbuf) )		/* syntax error */
++    if ( !compilePattern(patbuf, &cbuf) )	/* syntax error */
+       fail;
+     dot = (patbuf[0] == '.');			/* do dots as well */
+ 
+@@ -503,12 +510,16 @@ expand(const char *pattern, GlobInfo info)
+       char path[MAXPATHLEN];
+       char tmp[MAXPATHLEN];
+       const char *current = expand_entry(info, info->start);
++      size_t clen = strlen(current);
++
++      if ( clen+prefix_len+1 > sizeof(path) )
++	continue;
+ 
+       strcpy(path, current);
+-      strcat(path, prefix);
++      strcpy(&path[clen], prefix);
+ 
+       if ( (d=opendir(path[0] ? OsPath(path, tmp) : ".")) )
+-      { size_t plen = strlen(path);
++      { size_t plen = clen+prefix_len;
+ 
+ 	if ( plen > 0 && path[plen-1] != '/' )
+ 	  path[plen++] = '/';
+@@ -522,12 +533,11 @@ expand(const char *pattern, GlobInfo info)
+ 	       matchPattern(e->d_name, &cbuf) )
+ 	  { char newp[MAXPATHLEN];
+ 
+-	    strcpy(newp, path);
+-	    strcpy(&newp[plen], e->d_name);
+-/*	    if ( !tail[0] || ExistsDirectory(newp) )
+-	    Saves memory, but involves one more file-access
+-*/
++	    if ( plen+strlen(e->d_name)+1 < sizeof(newp) )
++	    { strcpy(newp, path);
++	      strcpy(&newp[plen], e->d_name);
+ 	      add_path(newp, info);
++	    }
+ 	  }
+ 	}
+ 	closedir(d);
+-- 
+1.7.11.7
+
diff --git a/pl.spec b/pl.spec
index 4a1537d..0c4fdff 100644
--- a/pl.spec
+++ b/pl.spec
@@ -29,6 +29,8 @@ Patch3:     %{name}-6.0.2-jni.patch
 Patch4:     %{name}-5.10.5-pc.patch
 # Fix CVE-2012-6089, in upstream 6.2.5, bug #891666
 Patch5:     %{name}-6.0.2-CVE-2012-6089.patch
+# Fix CVE-2012-6090, in upstream 6.2.5, bug #891666
+Patch6:     %{name}-6.0.2-CVE-2012-6090.patch
 
 # Base
 BuildRequires:  gmp-devel
@@ -168,6 +170,7 @@ in Prolog. In both setups it provides a re-entrant bidirectional interface.
 %patch3 -p1 -b .jni
 %patch4 -p1 -b .pc
 %patch5 -p1 -b .CVE-2012-6089
+%patch6 -p1 -b .CVE-2012-6090
 (
    cd src
    autoconf
@@ -329,6 +332,8 @@ rm $RPM_BUILD_ROOT%{_libdir}/swipl-%{version}/xpce/bin/*-linux/xpce-client
 %changelog
 * Fri Jan 04 2013 Petr Pisar <ppisar at redhat.com> - 6.0.2-4
 - Fix CVE-2012-6089 (buffer overflows in path canonisation code) (bug #891666)
+- Fix CVE-2012-6090 (buffer overflows when expanding file-names with long
+  paths) (bug #891666)
 
 * Thu Mar 22 2012 Petr Pisar <ppisar at redhat.com> - 6.0.2-3
 - Remove JDK version constrain by hacking JDK paths (bug #740897)