[issue13148] simple bug in mmap size check

[Maxim Yanchenko]

New submission from Maxim Yanchenko <maxim.yanchenko at gs.com>:

The condition contradicts the exception text:
            if (offset >= st.st_size) {
                PyErr_SetString(PyExc_ValueError,
                                "mmap offset is greater than file size");
                return NULL;
            }
The condition should be changed to (offset > st.st_size), similar to the later condition which is correct:
        } else if (offset + (size_t)map_size > st.st_size) {
            PyErr_SetString(PyExc_ValueError,
                            "mmap length is greater than file size");
            return NULL;
        }

The patch is attached.

----------
components: Library (Lib)
files: mmap-greater.patch
keywords: patch
messages: 145319
nosy: jazzer
priority: normal
severity: normal
status: open
title: simple bug in mmap size check
type: behavior
versions: Python 2.7
Added file: http://bugs.python.org/file23372/mmap-greater.patch

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<http://bugs.python.org/issue13148>
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