Bug 1127310

python-2.7.7-3.fc21.ppc64p7
glibc-2.19.90-31.fc21.ppc64p7
attr-2.4.47-7.fc21.ppc64


Recently the testcases for pyxattr have been turned on.  Which results in the following:

http://ppc.koji.fedoraproject.org/kojifiles/work/tasks/7128/1977128/build.log
...
ERROR: testBinaryPayload (test.test_xattr.xattrTest)
test binary values
----------------------------------------------------------------------
Traceback (most recent call last):
  File "/builddir/build/BUILD/pyxattr-0.5.3/test/test_xattr.py", line 351, in testBinaryPayload
    xattr.set(fname, self.USER_ATTR, BINVAL)
IOError: [Errno 22] Invalid argument
...


The function in question is:

...
static PyObject *
xattr_set(PyObject *self, PyObject *args, PyObject *keywds)
{
    PyObject *myarg, *res;
    int nofollow = 0;
    char *attrname = NULL;
    char *buf = NULL;
    int bufsize;
    int nret;
    int flags = 0;
    target_t tgt;
    const char *ns = NULL;
    char *newname;
    const char *full_name;
    static char *kwlist[] = {"item", "name", "value", "flags",
                             "nofollow", "namespace", NULL};

    /* Parse the arguments */
    if (!PyArg_ParseTupleAndKeywords(args, keywds, "Oetet#|ii" BYTES_CHAR,
                                     kwlist, &myarg, NULL, &attrname, NULL,
                                     &buf, &bufsize, &flags, &nofollow, &ns))
        return NULL;
    if(convert_obj(myarg, &tgt, nofollow) < 0) {
        res = NULL;
        goto freearg;
    }

    if(merge_ns(ns, attrname, &full_name, &newname) < 0) {
        res = NULL;
        goto freearg;
    }

    /* Set the attribute's value */
    nret = _set_obj(&tgt, full_name, buf, bufsize, flags);

    PyMem_Free(newname);

    free_tgt(&tgt);

    if(nret == -1) {
        res = PyErr_SetFromErrno(PyExc_IOError);
        goto freearg;
    }

    Py_INCREF(Py_None);
    res = Py_None;

 freearg:
    PyMem_Free(attrname);
    PyMem_Free(buf);

    /* Return the result */
    return res;
}
...


Running gdb on the testcase:


<mock-chroot>[root@bluebill ~]# (cd /builddir/build/BUILD/pyxattr-0.5.3/; export TEST_IGNORE_XATTRS=security.selinux; gdb /usr/bin/python2)
...
(gdb) path /builddir/build/BUILDROOT/pyxattr-0.5.3-1.fc21.ppc64/usr/lib64/python2.7/site-packages/
Executable and object file path: /builddir/build/BUILDROOT/pyxattr-0.5.3-1.fc21.ppc64/usr/lib64/python2.7/site-packages:/usr/local/sbin:/usr/bin:/bin:/usr/sbin:/sbin:/builddir/.local/bin:/builddir/bin
(gdb) break xattr_set
(gdb) run setup.py test
...
Breakpoint 1, xattr_set (self=0x0, args=('/builddir/build/BUILD/pyxattr-0.5.3/xattr-dhsdg0.test', u'user.test', 'abc\x00def'),
    keywds=0x0) at xattr.c:668
668     {
(gdb) print self
$1 = 0x0
(gdb) print args
$2 = ('/builddir/build/BUILD/pyxattr-0.5.3/xattr-dhsdg0.test', u'user.test', 'abc\x00def')
(gdb) print keywds
$3 = 0x0
(gdb) break _set_obj
Breakpoint 2 at 0x3fffaff32940: file xattr.c, line 216.
(gdb) c
Continuing.

Breakpoint 2, _set_obj (tgt=0x3fffffff8d90, name=0x10322cf0 "user.test", value=0x100f28b0, size=0, flags=7) at xattr.c:216
216                         const void *value, size_t size, int flags) {
(gdb) print value
$5 = (const void *) 0x100f28b0
(gdb) x/8b value
0x100f28b0:     0x61    0x62    0x63    0x00    0x64    0x65    0x66    0x00
(gdb) print size
$6 = 0
(gdb) print flags
$7 = 7



So it seems that bufsize should result in 7, but turns out to contain 0.