integer overflow in read_packet() [CVE-2013-2064]

[free-sw/xcb/libxcb] / src / xcb_in.c

diff --git a/src/xcb_in.c b/src/xcb_in.c
index fdcc813..8a7af92 100644 (file)
--- a/src/xcb_in.c
+++ b/src/xcb_in.c
@@ -25,6 +25,10 @@
 
 /* Stuff that reads stuff from the server. */
 
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+
 #include <assert.h>
 #include <string.h>
 #include <stdlib.h>
@@ -51,11 +55,6 @@
 #define XCB_REPLY 1
 #define XCB_XGE_EVENT 35
 
-/* required for compiling for Win32 using MinGW */
-#ifndef MSG_WAITALL
-#define MSG_WAITALL 0
-#endif
-
 struct event_list {
     xcb_generic_event_t *event;
     struct event_list *next;
@@ -94,8 +93,9 @@ static void remove_finished_readers(reader_list **prev_reader, uint64_t complete
 static int read_packet(xcb_connection_t *c)
 {
     xcb_generic_reply_t genrep;
-    int length = 32;
-    int eventlength = 0; /* length after first 32 bytes for GenericEvents */
+    uint64_t length = 32;
+    uint64_t eventlength = 0; /* length after first 32 bytes for GenericEvents */
+    uint64_t bufsize;
     void *buf;
     pending_reply *pend = 0;
     struct event_list *event;
@@ -170,8 +170,12 @@ static int read_packet(xcb_connection_t *c)
     if ((genrep.response_type & 0x7f) == XCB_XGE_EVENT)
         eventlength = genrep.length * 4;
 
-    buf = malloc(length + eventlength +
-            (genrep.response_type == XCB_REPLY ? 0 : sizeof(uint32_t)));
+    bufsize = length + eventlength +
+        (genrep.response_type == XCB_REPLY ? 0 : sizeof(uint32_t));
+    if (bufsize < INT32_MAX)
+        buf = malloc((size_t) bufsize);
+    else
+        buf = NULL;
     if(!buf)
     {
         _xcb_conn_shutdown(c, XCB_CONN_CLOSED_MEM_INSUFFICIENT);
@@ -269,11 +273,7 @@ static int read_block(const int fd, void *buf, const ssize_t len)
     int done = 0;
     while(done < len)
     {
-#ifdef __APPLE__
-        int ret = read(fd, ((char *) buf) + done, len - done);
-#else
-        int ret = recv(fd, ((char *) buf) + done, len - done,MSG_WAITALL);
-#endif
+        int ret = recv(fd, ((char *) buf) + done, len - done, 0);
         if(ret > 0)
             done += ret;
 #ifndef _WIN32
@@ -665,11 +665,7 @@ void _xcb_in_replies_done(xcb_connection_t *c)
 
 int _xcb_in_read(xcb_connection_t *c)
 {
-#ifdef __APPLE__
-    int n = read(c->fd, c->in.queue + c->in.queue_len, sizeof(c->in.queue) - c->in.queue_len);
-#else
-    int n = recv(c->fd, c->in.queue + c->in.queue_len, sizeof(c->in.queue) - c->in.queue_len,MSG_WAITALL);
-#endif
+    int n = recv(c->fd, c->in.queue + c->in.queue_len, sizeof(c->in.queue) - c->in.queue_len, 0);
     if(n > 0)
         c->in.queue_len += n;
     while(read_packet(c))