CVE-2014-3707.patch

From 3696fc1ba79d9b34660c44150be5e93ecf87dd9e Mon Sep 17 00:00:00 2001
From: Daniel Stenberg <daniel@haxx.se>
Date: Fri, 17 Oct 2014 12:59:32 +0200
Subject: [PATCH] curl_easy_duphandle: CURLOPT_COPYPOSTFIELDS read out of
 bounds

When duplicating a handle, the data to post was duplicated using
strdup() when it could be binary and contain zeroes and it was not even
zero terminated! This caused read out of bounds crashes/segfaults.

Since the lib/strdup.c file no longer is easily shared with the curl
tool with this change, it now uses its own version instead.

Bug: https://curl.haxx.se/docs/adv_20141105.html
CVE: CVE-2014-3707
Reported-By: Symeon Paraschoudis
---
 lib/formdata.c    | 52 +++++++++-------------------------------------------
 lib/strdup.c      | 32 +++++++++++++++++++++++++++-----
 lib/strdup.h      |  3 ++-
 lib/url.c         | 22 +++++++++++++++++-----
 lib/urldata.h     | 11 +++++++++--
 src/Makefile.inc  |  4 ++--
 src/tool_setup.h  |  5 ++---
 src/tool_strdup.c | 47 +++++++++++++++++++++++++++++++++++++++++++++++
 src/tool_strdup.h | 30 ++++++++++++++++++++++++++++++
 9 files changed, 145 insertions(+), 61 deletions(-)
 create mode 100644 src/tool_strdup.c
 create mode 100644 src/tool_strdup.h

diff --git a/lib/formdata.c b/lib/formdata.c
index 1abfbc4..73d3b6d 100644
--- a/lib/formdata.c
+++ b/lib/formdata.c
@@ -34,10 +34,11 @@
 #include "formdata.h"
 #include "vtls/vtls.h"
 #include "strequal.h"
 #include "curl_memory.h"
 #include "sendf.h"
+#include "strdup.h"
 
 #define _MPRINTF_REPLACE /* use our functions only */
 #include <curl/mprintf.h>
 
 /* The last #include file should be: */
@@ -208,50 +209,10 @@ static const char *ContentTypeForFilename(const char *filename,
   return contenttype;
 }
 
 /***************************************************************************
  *
- * memdup()
- *
- * Copies the 'source' data to a newly allocated buffer buffer (that is
- * returned). Uses buffer_length if not null, else uses strlen to determine
- * the length of the buffer to be copied
- *
- * Returns the new pointer or NULL on failure.
- *
- ***************************************************************************/
-static char *memdup(const char *src, size_t buffer_length)
-{
-  size_t length;
-  bool add = FALSE;
-  char *buffer;
-
-  if(buffer_length)
-    length = buffer_length;
-  else if(src) {
-    length = strlen(src);
-    add = TRUE;
-  }
-  else
-    /* no length and a NULL src pointer! */
-    return strdup("");
-
-  buffer = malloc(length+add);
-  if(!buffer)
-    return NULL; /* fail */
-
-  memcpy(buffer, src, length);
-
-  /* if length unknown do null termination */
-  if(add)
-    buffer[length] = '\0';
-
-  return buffer;
-}
-
-/***************************************************************************
- *
  * FormAdd()
  *
  * Stores a formpost parameter and builds the appropriate linked list.
  *
  * Has two principal functionalities: using files and byte arrays as
@@ -676,24 +637,29 @@ CURLFORMcode FormAdd(struct curl_httppost **httppost,
         }
         if(!(form->flags & HTTPPOST_PTRNAME) &&
            (form == first_form) ) {
           /* Note that there's small risk that form->name is NULL here if the
              app passed in a bad combo, so we better check for that first. */
-          if(form->name)
+          if(form->name) {
             /* copy name (without strdup; possibly contains null characters) */
-            form->name = memdup(form->name, form->namelength);
+            form->name = Curl_memdup(form->name, form->namelength?
+                                     form->namelength:
+                                     strlen(form->name)+1);
+          }
           if(!form->name) {
             return_value = CURL_FORMADD_MEMORY;
             break;
           }
           form->name_alloc = TRUE;
         }
         if(!(form->flags & (HTTPPOST_FILENAME | HTTPPOST_READFILE |
                             HTTPPOST_PTRCONTENTS | HTTPPOST_PTRBUFFER |
                             HTTPPOST_CALLBACK)) && form->value) {
           /* copy value (without strdup; possibly contains null characters) */
-          form->value = memdup(form->value, form->contentslength);
+          form->value = Curl_memdup(form->value, form->contentslength?
+                                    form->contentslength:
+                                    strlen(form->value)+1);
           if(!form->value) {
             return_value = CURL_FORMADD_MEMORY;
             break;
           }
           form->value_alloc = TRUE;
diff --git a/lib/strdup.c b/lib/strdup.c
index 3b776b1..4b5bd40 100644
--- a/lib/strdup.c
+++ b/lib/strdup.c
@@ -3,11 +3,11 @@
  *  Project                     ___| | | |  _ \| |
  *                             / __| | | | |_) | |
  *                            | (__| |_| |  _ <| |___
  *                             \___|\___/|_| \_\_____|
  *
- * Copyright (C) 1998 - 2012, Daniel Stenberg, <daniel@haxx.se>, et al.
+ * Copyright (C) 1998 - 2014, Daniel Stenberg, <daniel@haxx.se>, et al.
  *
  * This software is licensed as described in the file COPYING, which
  * you should have received as part of this distribution. The terms
  * are also available at https://curl.haxx.se/docs/copyright.html.
  *
@@ -17,16 +17,16 @@
  *
  * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
  * KIND, either express or implied.
  *
  ***************************************************************************/
-/*
- * This file is 'mem-include-scan' clean. See test 1132.
- */
 #include "curl_setup.h"
-
 #include "strdup.h"
+#include "curl_memory.h"
+
+/* The last #include file should be: */
+#include "memdebug.h"
 
 #ifndef HAVE_STRDUP
 char *curlx_strdup(const char *str)
 {
   size_t len;
@@ -48,5 +48,27 @@ char *curlx_strdup(const char *str)
 
   return newstr;
 
 }
 #endif
+
+/***************************************************************************
+ *
+ * Curl_memdup(source, length)
+ *
+ * Copies the 'source' data to a newly allocated buffer (that is
+ * returned). Copies 'length' bytes.
+ *
+ * Returns the new pointer or NULL on failure.
+ *
+ ***************************************************************************/
+char *Curl_memdup(const char *src, size_t length)
+{
+  char *buffer = malloc(length);
+  if(!buffer)
+    return NULL; /* fail */
+
+  memcpy(buffer, src, length);
+
+  /* if length unknown do null termination */
+  return buffer;
+}
diff --git a/lib/strdup.h b/lib/strdup.h
index 49af911..23a71f8 100644
--- a/lib/strdup.h
+++ b/lib/strdup.h
@@ -5,11 +5,11 @@
  *  Project                     ___| | | |  _ \| |
  *                             / __| | | | |_) | |
  *                            | (__| |_| |  _ <| |___
  *                             \___|\___/|_| \_\_____|
  *
- * Copyright (C) 1998 - 2010, Daniel Stenberg, <daniel@haxx.se>, et al.
+ * Copyright (C) 1998 - 2014, Daniel Stenberg, <daniel@haxx.se>, et al.
  *
  * This software is licensed as described in the file COPYING, which
  * you should have received as part of this distribution. The terms
  * are also available at https://curl.haxx.se/docs/copyright.html.
  *
@@ -24,7 +24,8 @@
 #include "curl_setup.h"
 
 #ifndef HAVE_STRDUP
 extern char *curlx_strdup(const char *str);
 #endif
+char *Curl_memdup(const char *src, size_t buffer_length);
 
 #endif /* HEADER_CURL_STRDUP_H */
diff --git a/lib/url.c b/lib/url.c
index 4974a1a..40d4fed 100644
--- a/lib/url.c
+++ b/lib/url.c
@@ -123,10 +123,11 @@ int curl_win32_idn_to_ascii(const char *in, char **out);
 #include "bundles.h"
 #include "conncache.h"
 #include "multihandle.h"
 #include "pipeline.h"
 #include "dotdot.h"
+#include "strdup.h"
 
 #define _MPRINTF_REPLACE /* use our functions only */
 #include <curl/mprintf.h>
 
 #include "curl_memory.h"
@@ -268,12 +269,13 @@ static const struct Curl_handler Curl_handler_dummy = {
 
 void Curl_freeset(struct SessionHandle *data)
 {
   /* Free all dynamic strings stored in the data->set substructure. */
   enum dupstring i;
-  for(i=(enum dupstring)0; i < STRING_LAST; i++)
+  for(i=(enum dupstring)0; i < STRING_LAST; i++) {
     Curl_safefree(data->set.str[i]);
+  }
 
   if(data->change.referer_alloc) {
     Curl_safefree(data->change.referer);
     data->change.referer_alloc = FALSE;
   }
@@ -354,18 +356,28 @@ CURLcode Curl_dupset(struct SessionHandle *dst, struct SessionHandle *src)
 
   /* clear all string pointers first */
   memset(dst->set.str, 0, STRING_LAST * sizeof(char *));
 
   /* duplicate all strings */
-  for(i=(enum dupstring)0; i< STRING_LAST; i++) {
+  for(i=(enum dupstring)0; i< STRING_LASTZEROTERMINATED; i++) {
     result = setstropt(&dst->set.str[i], src->set.str[i]);
     if(result)
-      break;
+      return result;
   }
 
-  /* If a failure occurred, freeing has to be performed externally. */
-  return result;
+  /* duplicate memory areas pointed to */
+  i = STRING_COPYPOSTFIELDS;
+  if(src->set.postfieldsize && src->set.str[i]) {
+    /* postfieldsize is curl_off_t, Curl_memdup() takes a size_t ... */
+    dst->set.str[i] = Curl_memdup(src->set.str[i], src->set.postfieldsize);
+    if(!dst->set.str[i])
+      return CURLE_OUT_OF_MEMORY;
+    /* point to the new copy */
+    dst->set.postfields = dst->set.str[i];
+  }
+
+  return CURLE_OK;
 }
 
 /*
  * This is the internal function curl_easy_cleanup() calls. This should
  * cleanup and free all resources associated with this sessionhandle.
diff --git a/lib/urldata.h b/lib/urldata.h
index 5a65c4a..62a2b80 100644
--- a/lib/urldata.h
+++ b/lib/urldata.h
@@ -1370,11 +1370,10 @@ enum dupstring {
   STRING_KEY_PASSWD,      /* plain text private key password */
   STRING_KEY_TYPE,        /* format for private key (default: PEM) */
   STRING_KRB_LEVEL,       /* krb security level */
   STRING_NETRC_FILE,      /* if not NULL, use this instead of trying to find
                              $HOME/.netrc */
-  STRING_COPYPOSTFIELDS,  /* if POST, set the fields' values here */
   STRING_PROXY,           /* proxy to use */
   STRING_SET_RANGE,       /* range, if used */
   STRING_SET_REFERER,     /* custom string for the HTTP referer field */
   STRING_SET_URL,         /* what original URL to work on */
   STRING_SSL_CAPATH,      /* CA directory name (doesn't work on windows) */
@@ -1413,11 +1412,19 @@ enum dupstring {
   STRING_TLSAUTH_PASSWORD,     /* TLS auth <password> */
 #endif
 
   STRING_BEARER,          /* <bearer>, if used */
 
-  /* -- end of strings -- */
+  /* -- end of zero-terminated strings -- */
+
+  STRING_LASTZEROTERMINATED,
+
+  /* -- below this are pointers to binary data that cannot be strdup'ed.
+     Each such pointer must be added manually to Curl_dupset() --- */
+
+  STRING_COPYPOSTFIELDS,  /* if POST, set the fields' values here */
+
   STRING_LAST /* not used, just an end-of-list marker */
 };
 
 struct UserDefined {
   FILE *err;         /* the stderr user data goes here */
diff --git a/src/Makefile.inc b/src/Makefile.inc
index 64d55ec..401a635 100644
--- a/src/Makefile.inc
+++ b/src/Makefile.inc
@@ -9,19 +9,17 @@
 
 # libcurl has sources that provide functions named curlx_* that aren't part of
 # the official API, but we re-use the code here to avoid duplication.
 CURLX_CFILES = \
 	../lib/strtoofft.c \
-	../lib/strdup.c \
 	../lib/rawstr.c \
 	../lib/nonblock.c \
 	../lib/warnless.c
 
 CURLX_HFILES = \
 	../lib/curl_setup.h \
 	../lib/strtoofft.h \
-	../lib/strdup.h \
 	../lib/rawstr.h \
 	../lib/nonblock.h \
 	../lib/warnless.h
 
 CURL_CFILES = \
@@ -53,10 +51,11 @@ CURL_CFILES = \
 	tool_operate.c \
 	tool_operhlp.c \
 	tool_panykey.c \
 	tool_paramhlp.c \
 	tool_parsecfg.c \
+	tool_strdup.c \
 	tool_setopt.c \
 	tool_sleep.c \
 	tool_urlglob.c \
 	tool_util.c \
 	tool_vms.c \
@@ -97,10 +96,11 @@ CURL_HFILES = \
 	tool_parsecfg.h \
 	tool_sdecls.h \
 	tool_setopt.h \
 	tool_setup.h \
 	tool_sleep.h \
+	tool_strdup.h \
 	tool_urlglob.h \
 	tool_util.h \
 	tool_version.h \
 	tool_vms.h \
 	tool_writeenv.h \
diff --git a/src/tool_setup.h b/src/tool_setup.h
index c94686f..3d7c158 100644
--- a/src/tool_setup.h
+++ b/src/tool_setup.h
@@ -5,11 +5,11 @@
  *  Project                     ___| | | |  _ \| |
  *                             / __| | | | |_) | |
  *                            | (__| |_| |  _ <| |___
  *                             \___|\___/|_| \_\_____|
  *
- * Copyright (C) 1998 - 2012, Daniel Stenberg, <daniel@haxx.se>, et al.
+ * Copyright (C) 1998 - 2014, Daniel Stenberg, <daniel@haxx.se>, et al.
  *
  * This software is licensed as described in the file COPYING, which
  * you should have received as part of this distribution. The terms
  * are also available at https://curl.haxx.se/docs/copyright.html.
  *
@@ -65,11 +65,10 @@
    /* define what to use for unprintable characters */
 #  define UNPRINTABLE_CHAR '.'
 #endif
 
 #ifndef HAVE_STRDUP
-#  include "strdup.h"
-#  define strdup(ptr) curlx_strdup(ptr)
+#  include "tool_strdup.h"
 #endif
 
 #endif /* HEADER_CURL_TOOL_SETUP_H */
 
diff --git a/src/tool_strdup.c b/src/tool_strdup.c
new file mode 100644
index 0000000..d661a82
--- /dev/null
+++ b/src/tool_strdup.c
@@ -0,0 +1,47 @@
+/***************************************************************************
+ *                                  _   _ ____  _
+ *  Project                     ___| | | |  _ \| |
+ *                             / __| | | | |_) | |
+ *                            | (__| |_| |  _ <| |___
+ *                             \___|\___/|_| \_\_____|
+ *
+ * Copyright (C) 1998 - 2014, Daniel Stenberg, <daniel@haxx.se>, et al.
+ *
+ * This software is licensed as described in the file COPYING, which
+ * you should have received as part of this distribution. The terms
+ * are also available at https://curl.haxx.se/docs/copyright.html.
+ *
+ * You may opt to use, copy, modify, merge, publish, distribute and/or sell
+ * copies of the Software, and permit persons to whom the Software is
+ * furnished to do so, under the terms of the COPYING file.
+ *
+ * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
+ * KIND, either express or implied.
+ *
+ ***************************************************************************/
+#include "strdup.h"
+
+#ifndef HAVE_STRDUP
+char *strdup(const char *str)
+{
+  size_t len;
+  char *newstr;
+
+  if(!str)
+    return (char *)NULL;
+
+  len = strlen(str);
+
+  if(len >= ((size_t)-1) / sizeof(char))
+    return (char *)NULL;
+
+  newstr = malloc((len+1)*sizeof(char));
+  if(!newstr)
+    return (char *)NULL;
+
+  memcpy(newstr,str,(len+1)*sizeof(char));
+
+  return newstr;
+
+}
+#endif
diff --git a/src/tool_strdup.h b/src/tool_strdup.h
new file mode 100644
index 0000000..83c8102
--- /dev/null
+++ b/src/tool_strdup.h
@@ -0,0 +1,30 @@
+#ifndef HEADER_TOOL_STRDUP_H
+#define HEADER_TOOL_STRDUP_H
+/***************************************************************************
+ *                                  _   _ ____  _
+ *  Project                     ___| | | |  _ \| |
+ *                             / __| | | | |_) | |
+ *                            | (__| |_| |  _ <| |___
+ *                             \___|\___/|_| \_\_____|
+ *
+ * Copyright (C) 1998 - 2014, Daniel Stenberg, <daniel@haxx.se>, et al.
+ *
+ * This software is licensed as described in the file COPYING, which
+ * you should have received as part of this distribution. The terms
+ * are also available at https://curl.haxx.se/docs/copyright.html.
+ *
+ * You may opt to use, copy, modify, merge, publish, distribute and/or sell
+ * copies of the Software, and permit persons to whom the Software is
+ * furnished to do so, under the terms of the COPYING file.
+ *
+ * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
+ * KIND, either express or implied.
+ *
+ ***************************************************************************/
+#include "tool_setup.h"
+
+#ifndef HAVE_STRDUP
+extern char *strdup(const char *str);
+#endif
+
+#endif /* HEADER_TOOL_STRDUP_H */
-- 
2.1.1