truncate rc to INT_MAX

to avoid overflow for large messages

send/recv still succeed for large messages,
but `zmq_msg_size` must be used to get the true size.

Makefile.am

@@ -324,6 +324,7 @@ test_apps = \
 	tests/test_invalid_rep \
 	tests/test_msg_flags \
 	tests/test_msg_ffn \
+	tests/test_large_msg \
 	tests/test_connect_resolve \
 	tests/test_immediate \
 	tests/test_last_endpoint \
@@ -425,6 +426,9 @@ tests_test_msg_flags_LDADD = src/libzmq.la
 tests_test_msg_ffn_SOURCES = tests/test_msg_ffn.cpp
 tests_test_msg_ffn_LDADD = src/libzmq.la
 
+tests_test_large_msg_SOURCES = tests/test_large_msg.cpp
+tests_test_large_msg_LDADD = src/libzmq.la
+
 tests_test_connect_resolve_SOURCES = tests/test_connect_resolve.cpp
 tests_test_connect_resolve_LDADD = src/libzmq.la
 

src/zmq.cpp

@@ -346,11 +346,12 @@ int zmq_disconnect (void *s_, const char *addr_)
 static int
 s_sendmsg (zmq::socket_base_t *s_, zmq_msg_t *msg_, int flags_)
 {
-    int sz = (int) zmq_msg_size (msg_);
+    size_t sz = zmq_msg_size (msg_);
     int rc = s_->send ((zmq::msg_t *) msg_, flags_);
     if (unlikely (rc < 0))
         return -1;
-    return sz;
+    // truncate returned size to INT_MAX to avoid overflow to negative values
+    return (int) (sz < INT_MAX ? sz : INT_MAX);
 }
 
 /*  To be deprecated once zmq_msg_send() is stable                           */
@@ -460,7 +461,9 @@ s_recvmsg (zmq::socket_base_t *s_, zmq_msg_t *msg_, int flags_)
     int rc = s_->recv ((zmq::msg_t*) msg_, flags_);
     if (unlikely (rc < 0))
         return -1;
-    return (int) zmq_msg_size (msg_);
+    // truncate returned size to INT_MAX to avoid overflow to negative values
+    size_t sz = zmq_msg_size (msg_);
+    return (int) (sz < INT_MAX ? sz : INT_MAX);
 }
 
 /*  To be deprecated once zmq_msg_recv() is stable                           */

tests/test_large_msg

+#! /bin/sh
+
+# tests/test_large_msg - temporary wrapper script for .libs/test_large_msg
+# Generated by libtool (GNU libtool) 2.4.6
+#
+# The tests/test_large_msg program cannot be directly executed until all the libtool
+# libraries that it depends on are installed.
+#
+# This wrapper script should never be moved out of the build directory.
+# If it is, it will not operate correctly.
+
+# Sed substitution that helps us do robust quoting.  It backslashifies
+# metacharacters that are still active within double-quoted strings.
+sed_quote_subst='s|\([`"$\\]\)|\\\1|g'
+
+# Be Bourne compatible
+if test -n "${ZSH_VERSION+set}" && (emulate sh) >/dev/null 2>&1; then
+  emulate sh
+  NULLCMD=:
+  # Zsh 3.x and 4.x performs word splitting on ${1+"$@"}, which
+  # is contrary to our usage.  Disable this feature.
+  alias -g '${1+"$@"}'='"$@"'
+  setopt NO_GLOB_SUBST
+else
+  case `(set -o) 2>/dev/null` in *posix*) set -o posix;; esac
+fi
+BIN_SH=xpg4; export BIN_SH # for Tru64
+DUALCASE=1; export DUALCASE # for MKS sh
+
+# The HP-UX ksh and POSIX shell print the target directory to stdout
+# if CDPATH is set.
+(unset CDPATH) >/dev/null 2>&1 && unset CDPATH
+
+relink_command=""
+
+# This environment variable determines our operation mode.
+if test "$libtool_install_magic" = "%%%MAGIC variable%%%"; then
+  # install mode needs the following variables:
+  generated_by_libtool_version='2.4.6'
+  notinst_deplibs=' src/libzmq.la'
+else
+  # When we are sourced in execute mode, $file and $ECHO are already set.
+  if test "$libtool_execute_magic" != "%%%MAGIC variable%%%"; then
+    file="$0"
+
+# A function that is used when there is no print builtin or printf.
+func_fallback_echo ()
+{
+  eval 'cat <<_LTECHO_EOF
+$1
+_LTECHO_EOF'
+}
+    ECHO="printf %s\\n"
+  fi
+
+# Very basic option parsing. These options are (a) specific to
+# the libtool wrapper, (b) are identical between the wrapper
+# /script/ and the wrapper /executable/ that is used only on
+# windows platforms, and (c) all begin with the string --lt-
+# (application programs are unlikely to have options that match
+# this pattern).
+#
+# There are only two supported options: --lt-debug and
+# --lt-dump-script. There is, deliberately, no --lt-help.
+#
+# The first argument to this parsing function should be the
+# script's ./libtool value, followed by no.
+lt_option_debug=
+func_parse_lt_options ()
+{
+  lt_script_arg0=$0
+  shift
+  for lt_opt
+  do
+    case "$lt_opt" in
+    --lt-debug) lt_option_debug=1 ;;
+    --lt-dump-script)
+        lt_dump_D=`$ECHO "X$lt_script_arg0" | /usr/bin/sed -e 's/^X//' -e 's%/[^/]*$%%'`
+        test "X$lt_dump_D" = "X$lt_script_arg0" && lt_dump_D=.
+        lt_dump_F=`$ECHO "X$lt_script_arg0" | /usr/bin/sed -e 's/^X//' -e 's%^.*/%%'`
+        cat "$lt_dump_D/$lt_dump_F"
+        exit 0
+      ;;
+    --lt-*)
+        $ECHO "Unrecognized --lt- option: '$lt_opt'" 1>&2
+        exit 1
+      ;;
+    esac
+  done
+
+  # Print the debug banner immediately:
+  if test -n "$lt_option_debug"; then
+    echo "test_large_msg:tests/test_large_msg:$LINENO: libtool wrapper (GNU libtool) 2.4.6" 1>&2
+  fi
+}
+
+# Used when --lt-debug. Prints its arguments to stdout
+# (redirection is the responsibility of the caller)
+func_lt_dump_args ()
+{
+  lt_dump_args_N=1;
+  for lt_arg
+  do
+    $ECHO "test_large_msg:tests/test_large_msg:$LINENO: newargv[$lt_dump_args_N]: $lt_arg"
+    lt_dump_args_N=`expr $lt_dump_args_N + 1`
+  done
+}
+
+# Core function for launching the target application
+func_exec_program_core ()
+{
+
+      if test -n "$lt_option_debug"; then
+        $ECHO "test_large_msg:tests/test_large_msg:$LINENO: newargv[0]: $progdir/$program" 1>&2
+        func_lt_dump_args ${1+"$@"} 1>&2
+      fi
+      exec "$progdir/$program" ${1+"$@"}
+
+      $ECHO "$0: cannot exec $program $*" 1>&2
+      exit 1
+}
+
+# A function to encapsulate launching the target application
+# Strips options in the --lt-* namespace from $@ and
+# launches target application with the remaining arguments.
+func_exec_program ()
+{
+  case " $* " in
+  *\ --lt-*)
+    for lt_wr_arg
+    do
+      case $lt_wr_arg in
+      --lt-*) ;;
+      *) set x "$@" "$lt_wr_arg"; shift;;
+      esac
+      shift
+    done ;;
+  esac
+  func_exec_program_core ${1+"$@"}
+}
+
+  # Parse options
+  func_parse_lt_options "$0" ${1+"$@"}
+
+  # Find the directory that this script lives in.
+  thisdir=`$ECHO "$file" | /usr/bin/sed 's%/[^/]*$%%'`
+  test "x$thisdir" = "x$file" && thisdir=.
+
+  # Follow symbolic links until we get to the real thisdir.
+  file=`ls -ld "$file" | /usr/bin/sed -n 's/.*-> //p'`
+  while test -n "$file"; do
+    destdir=`$ECHO "$file" | /usr/bin/sed 's%/[^/]*$%%'`
+
+    # If there was a directory component, then change thisdir.
+    if test "x$destdir" != "x$file"; then
+      case "$destdir" in
+      [\\/]* | [A-Za-z]:[\\/]*) thisdir="$destdir" ;;
+      *) thisdir="$thisdir/$destdir" ;;
+      esac
+    fi
+
+    file=`$ECHO "$file" | /usr/bin/sed 's%^.*/%%'`
+    file=`ls -ld "$thisdir/$file" | /usr/bin/sed -n 's/.*-> //p'`
+  done
+
+  # Usually 'no', except on cygwin/mingw when embedded into
+  # the cwrapper.
+  WRAPPER_SCRIPT_BELONGS_IN_OBJDIR=no
+  if test "$WRAPPER_SCRIPT_BELONGS_IN_OBJDIR" = "yes"; then
+    # special case for '.'
+    if test "$thisdir" = "."; then
+      thisdir=`pwd`
+    fi
+    # remove .libs from thisdir
+    case "$thisdir" in
+    *[\\/].libs ) thisdir=`$ECHO "$thisdir" | /usr/bin/sed 's%[\\/][^\\/]*$%%'` ;;
+    .libs )   thisdir=. ;;
+    esac
+  fi
+
+  # Try to get the absolute directory name.
+  absdir=`cd "$thisdir" && pwd`
+  test -n "$absdir" && thisdir="$absdir"
+
+  program='test_large_msg'
+  progdir="$thisdir/.libs"
+
+
+  if test -f "$progdir/$program"; then
+    # Add our own library path to DYLD_LIBRARY_PATH
+    DYLD_LIBRARY_PATH="/Users/benjaminrk/dev/zmq/libzmq/src/.libs:$DYLD_LIBRARY_PATH"
+
+    # Some systems cannot cope with colon-terminated DYLD_LIBRARY_PATH
+    # The second colon is a workaround for a bug in BeOS R4 sed
+    DYLD_LIBRARY_PATH=`$ECHO "$DYLD_LIBRARY_PATH" | /usr/bin/sed 's/::*$//'`
+
+    export DYLD_LIBRARY_PATH
+
+    if test "$libtool_execute_magic" != "%%%MAGIC variable%%%"; then
+      # Run the actual program with our arguments.
+      func_exec_program ${1+"$@"}
+    fi
+  else
+    # The program doesn't exist.
+    $ECHO "$0: error: '$progdir/$program' does not exist" 1>&2
+    $ECHO "This script is just a wrapper for $program." 1>&2
+    $ECHO "See the libtool documentation for more information." 1>&2
+    exit 1
+  fi
+fi

tests/test_large_msg.cpp

+/*
+    Copyright (c) 2007-2015 Contributors as noted in the AUTHORS file
+
+    This file is part of libzmq, the ZeroMQ core engine in C++.
+
+    libzmq is free software; you can redistribute it and/or modify it under
+    the terms of the GNU Lesser General Public License (LGPL) as published
+    by the Free Software Foundation; either version 3 of the License, or
+    (at your option) any later version.
+
+    As a special exception, the Contributors give you permission to link
+    this library with independent modules to produce an executable,
+    regardless of the license terms of these independent modules, and to
+    copy and distribute the resulting executable under terms of your choice,
+    provided that you also meet, for each linked independent module, the
+    terms and conditions of the license of that module. An independent
+    module is a module which is not derived from or based on this library.
+    If you modify this library, you must extend this exception to your
+    version of the library.
+
+    libzmq is distributed in the hope that it will be useful, but WITHOUT
+    ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+    FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public
+    License for more details.
+
+    You should have received a copy of the GNU Lesser General Public License
+    along with this program.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+#include <limits.h>
+#include "testutil.hpp"
+
+int main (void)
+{
+    setup_test_environment();
+    void *ctx = zmq_ctx_new ();
+    assert (ctx);
+
+    void *sb = zmq_socket (ctx, ZMQ_PAIR);
+    assert (sb);
+    int rc = zmq_bind (sb, "tcp://127.0.0.1:5560");
+    assert (rc == 0);
+
+    void *sc = zmq_socket (ctx, ZMQ_PAIR);
+    assert (sc);
+    rc = zmq_connect (sc, "tcp://127.0.0.1:5560");
+    assert (rc == 0);
+    
+    zmq_msg_t msg, rcv;
+    size_t big = 64 + (size_t) INT_MAX;
+    printf("Large msg: %u %llu %lu\n", INT_MAX, SIZE_MAX, big);
+    
+    rc = zmq_msg_init_size (&msg, big);
+    assert (rc == 0);
+    size_t sz = zmq_msg_size(&msg);
+    assert (sz == big);
+    
+    rc = zmq_msg_send(&msg, sb, 0);
+    assert (rc >= 0);       // first check success
+    assert (rc == INT_MAX); // check truncated max return value
+    
+    rc = zmq_msg_close(&msg);
+    assert (rc == 0);
+    
+    rc = zmq_msg_init(&rcv);
+    assert (rc == 0);
+    
+    rc = zmq_msg_recv(&rcv, sc, 0);
+    assert (rc >= 0);       // first check success
+    assert (rc == INT_MAX); // check truncated max return value
+    
+    sz = zmq_msg_size(&rcv);
+    assert (sz == big); // check message is still the right size
+    
+    rc = zmq_msg_close(&rcv);
+    assert (rc == 0);
+    
+    rc = zmq_close (sc);
+    assert (rc == 0);
+
+    rc = zmq_close (sb);
+    assert (rc == 0);
+
+    rc = zmq_ctx_term (ctx);
+    assert (rc == 0);
+
+    return 0 ;
+}