diff --git a/Include/pyport.h b/Include/pyport.h
index 0c78a1e5b668d3..6987a577678a2c 100644
--- a/Include/pyport.h
+++ b/Include/pyport.h
@@ -947,4 +947,17 @@ typedef struct fd_set {
 #define Py_ULL(x) Py_LL(x##U)
 #endif
 
+#if defined (MS_WINDOWS) || defined(__APPLE__)
+    /* On Windows, the count parameter of read() is an int (bpo-9015, bpo-9611).
+       On macOS 10.13, read() and write() with more than INT_MAX bytes
+       fail with EINVAL (bpo-24658). */
+#   define _PY_READ_MAX  INT_MAX
+#   define _PY_WRITE_MAX INT_MAX
+#else
+    /* write() should truncate the input to PY_SSIZE_T_MAX bytes,
+       but it's safer to do it ourself to have a portable behaviour */
+#   define _PY_READ_MAX  PY_SSIZE_T_MAX
+#   define _PY_WRITE_MAX PY_SSIZE_T_MAX
+#endif
+
 #endif /* Py_PYPORT_H */
diff --git a/Lib/test/test_largefile.py b/Lib/test/test_largefile.py
index 16da8d8f174738..57725f2fc71999 100644
--- a/Lib/test/test_largefile.py
+++ b/Lib/test/test_largefile.py
@@ -8,7 +8,7 @@
 import sys
 import unittest
 from test.test_support import run_unittest, TESTFN, verbose, requires, \
-                              unlink
+                              unlink, bigmemtest
 import io  # C implementation of io
 import _pyio as pyio # Python implementation of io
 
@@ -48,6 +48,15 @@ def test_seek(self):
                 print('check file size with os.fstat')
             self.assertEqual(os.fstat(f.fileno())[stat.ST_SIZE], size+1)
 
+    # _pyio.FileIO.readall() uses a temporary bytearry then casted to bytes,
+    # so memuse=2 is needed
+    @bigmemtest(minsize=size, memuse=2)
+    def test_large_read(self, _size):
+        # bpo-24658: Test that a read greater than 2GB does not fail.
+        with self.open(TESTFN, "rb") as f:
+            self.assertEqual(len(f.read()), size + 1)
+            self.assertEqual(f.tell(), size + 1)
+
     def test_osstat(self):
         if verbose:
             print('check file size with os.stat')
@@ -186,6 +195,7 @@ class TestCase(LargeFileTest):
         suite.addTest(TestCase('test_osstat'))
         suite.addTest(TestCase('test_seek_read'))
         suite.addTest(TestCase('test_lseek'))
+        suite.addTest(TestCase('test_large_read'))
         with _open(TESTFN, 'wb') as f:
             if hasattr(f, 'truncate'):
                 suite.addTest(TestCase('test_truncate'))
diff --git a/Misc/NEWS.d/next/macOS/2018-10-18-02-20-38.bpo-24658.c7F8Pu.rst b/Misc/NEWS.d/next/macOS/2018-10-18-02-20-38.bpo-24658.c7F8Pu.rst
new file mode 100644
index 00000000000000..a6b50e15e75431
--- /dev/null
+++ b/Misc/NEWS.d/next/macOS/2018-10-18-02-20-38.bpo-24658.c7F8Pu.rst
@@ -0,0 +1,2 @@
+On macOS, fix reading from and writing into a file with a size larger than 2
+GiB.
diff --git a/Modules/_io/fileio.c b/Modules/_io/fileio.c
index 2b40ada195a1f5..eb117bc5aa2d73 100644
--- a/Modules/_io/fileio.c
+++ b/Modules/_io/fileio.c
@@ -515,9 +515,10 @@ fileio_readinto(fileio *self, PyObject *args)
         len = pbuf.len;
         Py_BEGIN_ALLOW_THREADS
         errno = 0;
+        if (len > _PY_READ_MAX) {
+            len = _PY_READ_MAX;
+        }
 #if defined(MS_WIN64) || defined(MS_WINDOWS)
-        if (len > INT_MAX)
-            len = INT_MAX;
         n = read(self->fd, pbuf.buf, (int)len);
 #else
         n = read(self->fd, pbuf.buf, len);
@@ -604,9 +605,10 @@ fileio_readall(fileio *self)
         Py_BEGIN_ALLOW_THREADS
         errno = 0;
         n = newsize - total;
+        if (n > _PY_READ_MAX) {
+            n = _PY_READ_MAX;
+        }
 #if defined(MS_WIN64) || defined(MS_WINDOWS)
-        if (n > INT_MAX)
-            n = INT_MAX;
         n = read(self->fd,
                  PyBytes_AS_STRING(result) + total,
                  (int)n);
@@ -668,10 +670,10 @@ fileio_read(fileio *self, PyObject *args)
         return fileio_readall(self);
     }
 
-#if defined(MS_WIN64) || defined(MS_WINDOWS)
-    if (size > INT_MAX)
-        size = INT_MAX;
-#endif
+    if (size > _PY_READ_MAX) {
+        size = _PY_READ_MAX;
+    }
+
     bytes = PyBytes_FromStringAndSize(NULL, size);
     if (bytes == NULL)
         return NULL;
@@ -723,9 +725,10 @@ fileio_write(fileio *self, PyObject *args)
         Py_BEGIN_ALLOW_THREADS
         errno = 0;
         len = pbuf.len;
+        if (len > _PY_WRITE_MAX) {
+            len = _PY_WRITE_MAX;
+        }
 #if defined(MS_WIN64) || defined(MS_WINDOWS)
-        if (len > INT_MAX)
-            len = INT_MAX;
         n = write(self->fd, pbuf.buf, (int)len);
 #else
         n = write(self->fd, pbuf.buf, len);
diff --git a/Modules/posixmodule.c b/Modules/posixmodule.c
index 7a1a6945c102eb..eebf9c9c5b539e 100644
--- a/Modules/posixmodule.c
+++ b/Modules/posixmodule.c
@@ -6805,6 +6805,9 @@ posix_read(PyObject *self, PyObject *args)
         return posix_error();
     }
     Py_BEGIN_ALLOW_THREADS
+    if (size > _PY_READ_MAX) {
+        size = _PY_READ_MAX;
+    }
     n = read(fd, PyString_AsString(buffer), size);
     Py_END_ALLOW_THREADS
     if (n < 0) {
@@ -6836,9 +6839,10 @@ posix_write(PyObject *self, PyObject *args)
     }
     len = pbuf.len;
     Py_BEGIN_ALLOW_THREADS
+    if (len > _PY_WRITE_MAX) {
+        len = _PY_WRITE_MAX;
+    }
 #if defined(MS_WIN64) || defined(MS_WINDOWS)
-    if (len > INT_MAX)
-        len = INT_MAX;
     size = write(fd, pbuf.buf, (int)len);
 #else
     size = write(fd, pbuf.buf, len);