Package: gftp
Version: 2.0.18-16
Severity: important
Tags: patch, security

gftp seems vulnerable to CVE-2006-7221:
http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2006-7221

"Multiple off-by-one errors in fsplib.c in fsplib before 0.8 allow
attackers to cause a denial of service via unspecified vectors involving
the (1) name and (2) d_name entry attributes."

Attached patch includes the upstream fsplib changes.

-- 
Kees Cook                                            @outflux.net
--- gftp-2.0.18.orig/lib/fsplib/fsplib.c
+++ gftp-2.0.18/lib/fsplib/fsplib.c
@@ -612,9 +612,9 @@
     entry->d_reclen = fentry.reclen;
     strncpy(entry->d_name,fentry.name,MAXNAMLEN);
 
-    if (fentry.namlen > MAXNAMLEN)
+    if (fentry.namlen >= MAXNAMLEN)
     {
-	entry->d_name[MAXNAMLEN + 1 ] = '\0';
+	entry->d_name[MAXNAMLEN] = '\0';
 #ifdef HAVE_NAMLEN
 	entry->d_namlen = MAXNAMLEN;
     } else
@@ -680,9 +680,19 @@
        /* skip file date and file size */
        dir->dirpos += 9;
        /* read file name */
-       entry->name[255 + 1] = '\0';
-       strncpy(entry->name,(char *)( dir->data + dir->dirpos ),MAXNAMLEN);
+       entry->name[255] = '\0';
+       strncpy(entry->name,(char *)( dir->data + dir->dirpos ),255);
+       /* check for ASCIIZ encoded filename */
+       if (memchr(dir->data + dir->dirpos,0,dir->datasize - dir->dirpos) != NULL)
+       {
        namelen = strlen( (char *) dir->data+dir->dirpos);
+       }
+       else
+       {
+            /* \0 terminator not found at end of filename */
+            *result = NULL;
+            return 0;
+       }
        /* skip over file name */
        dir->dirpos += namelen +1;
 
@@ -709,12 +719,12 @@
 
 struct dirent * fsp_readdir(FSP_DIR *dirp)
 {
-    static struct dirent entry;
+    static dirent_workaround entry;
     struct dirent *result;
     
     
     if (dirp == NULL) return NULL;
-    if ( fsp_readdir_r(dirp,&entry,&result) )
+    if ( fsp_readdir_r(dirp,&entry.dirent,&result) )
         return NULL;
     else
         return result;
--- gftp-2.0.18.orig/lib/fsplib/fsplib.h
+++ gftp-2.0.18/lib/fsplib/fsplib.h
@@ -1,13 +1,17 @@
 #ifndef _FSPLIB_H
 #define _FSPLIB_H 1
 #include <time.h>
+#include <dirent.h>
+#include <sys/stat.h>
+#include <stddef.h>
+
 /* The FSP v2 protocol support library - public interface */
 
 /*
 This file is part of fsplib - FSP protocol stack implemented in C
 language. See http://fsp.sourceforge.net for more information.
 
-Copyright (c) 2003-2005 by Radim HSN Kolar ([EMAIL PROTECTED])
+Copyright (c) 2003-2005 by Radim HSN Kolar ([EMAIL PROTECTED])
 
 You may copy or modify this file in any manner you wish, provided
 that this notice is always included, and that you hold the author
@@ -138,6 +142,12 @@
 		      unsigned int pos;          /* position of next packet */
 } FSP_FILE;
 
+
+typedef union dirent_workaround {
+      struct dirent dirent;
+      char fill[offsetof (struct dirent, d_name) + MAXNAMLEN + 1];
+} dirent_workaround;
+ 
 /* function prototypes */
 
 /* session management */

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