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: http://curl.haxx.se/docs/adv_20141105.html
CVE: CVE-2014-3707
Reported-By: Symeon Paraschoudis
diff --git a/lib/formdata.c b/lib/formdata.c
index 1abfbc4..73d3b6d 100644
--- a/lib/formdata.c
+++ b/lib/formdata.c
@@ -36,6 +36,7 @@
#include "strequal.h"
#include "curl_memory.h"
#include "sendf.h"
+#include "strdup.h"
#define _MPRINTF_REPLACE /* use our functions only */
#include <curl/mprintf.h>
@@ -210,46 +211,6 @@
/***************************************************************************
*
- * 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.
@@ -678,9 +639,12 @@
(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;
@@ -691,7 +655,9 @@
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;
diff --git a/lib/strdup.c b/lib/strdup.c
index 3b776b1..4b5bd40 100644
--- a/lib/strdup.c
+++ b/lib/strdup.c
@@ -5,7 +5,7 @@
* | (__| |_| | _ <| |___
* \___|\___/|_| \_\_____|
*
- * 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
@@ -19,12 +19,12 @@
* 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)
@@ -50,3 +50,25 @@
}
#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
@@ -7,7 +7,7 @@
* | (__| |_| | _ <| |___
* \___|\___/|_| \_\_____|
*
- * 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
@@ -26,5 +26,6 @@
#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
@@ -125,6 +125,7 @@
#include "multihandle.h"
#include "pipeline.h"
#include "dotdot.h"
+#include "strdup.h"
#define _MPRINTF_REPLACE /* use our functions only */
#include <curl/mprintf.h>
@@ -270,8 +271,9 @@
{
/* 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);
@@ -356,14 +358,24 @@
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;
}
/*
diff --git a/lib/urldata.h b/lib/urldata.h
index 5a65c4a..62a2b80 100644
--- a/lib/urldata.h
+++ b/lib/urldata.h
@@ -1372,7 +1372,6 @@
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 */
@@ -1415,7 +1414,15 @@
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 */
};
diff --git a/src/Makefile.inc b/src/Makefile.inc
index 64d55ec..401a635 100644
--- a/src/Makefile.inc
+++ b/src/Makefile.inc
@@ -11,7 +11,6 @@
# 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
@@ -19,7 +18,6 @@
CURLX_HFILES = \
../lib/curl_setup.h \
../lib/strtoofft.h \
- ../lib/strdup.h \
../lib/rawstr.h \
../lib/nonblock.h \
../lib/warnless.h
@@ -55,6 +53,7 @@
tool_panykey.c \
tool_paramhlp.c \
tool_parsecfg.c \
+ tool_strdup.c \
tool_setopt.c \
tool_sleep.c \
tool_urlglob.c \
@@ -99,6 +98,7 @@
tool_setopt.h \
tool_setup.h \
tool_sleep.h \
+ tool_strdup.h \
tool_urlglob.h \
tool_util.h \
tool_version.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
@@ -7,7 +7,7 @@
* | (__| |_| | _ <| |___
* \___|\___/|_| \_\_____|
*
- * 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
@@ -67,8 +67,7 @@
#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 http://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 http://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 */
