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gh-111178: Fix getsockaddrarg() undefined behavior #131668

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Merged
merged 12 commits into from
Apr 1, 2025
Merged

gh-111178: Fix getsockaddrarg() undefined behavior #131668

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88fc5c2
gh-111178: Fix getsockaddrarg() undefined behavior
vstinner Mar 24, 2025
1aebf4c
Simplify code
vstinner Mar 24, 2025
9eb932c
Initialize cid to 0
vstinner Mar 24, 2025
533a478
Use 'unsigned short' type
vstinner Mar 28, 2025
9968c1e
Use 'unsigned char'
vstinner Mar 28, 2025
a95b22d
Add NEWS entry
vstinner Mar 28, 2025
18ed09e
Use 'unsigned long' to parse channel on Windows
vstinner Mar 28, 2025
99dcf45
Fix BTPROTO_HCI on FreeBSD
vstinner Apr 1, 2025
c0d7d03
Update BTPROTO_HCI code
vstinner Apr 1, 2025
7178cfd
Change exception type to ValueError
vstinner Apr 1, 2025
94f7b6f
Remove outdated comments
vstinner Apr 1, 2025
7455bf5
Remove useless assignment
vstinner Apr 1, 2025
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1 change: 1 addition & 0 deletions Misc/NEWS.d/next/Library/2025-03-28-11-26-31.gh-issue-131668.tcS4xS.rst
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Original file line number Diff line number Diff line change
@@ -0,0 +1 @@
:mod:`socket`: Fix code parsing AF_BLUETOOTH socket addresses.
66 changes: 54 additions & 12 deletions Modules/socketmodule.c
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Original file line number Diff line number Diff line change
Expand Up @@ -1521,11 +1521,15 @@ makesockaddr(SOCKET_T sockfd, struct sockaddr *addr, size_t addrlen, int proto)
struct sockaddr_hci *a = (struct sockaddr_hci *) addr;
#if defined(__NetBSD__) || defined(__DragonFly__)
return makebdaddr(&_BT_HCI_MEMB(a, bdaddr));
#else /* __NetBSD__ || __DragonFly__ */
#elif defined(__FreeBSD__)
char *node = _BT_HCI_MEMB(a, node);
size_t len = strnlen(node, sizeof(_BT_HCI_MEMB(a, node)));
return PyBytes_FromStringAndSize(node, (Py_ssize_t)len);
#else
PyObject *ret = NULL;
ret = Py_BuildValue("i", _BT_HCI_MEMB(a, dev));
return ret;
#endif /* !(__NetBSD__ || __DragonFly__) */
#endif
}

#if !defined(__FreeBSD__)
Expand Down Expand Up @@ -2044,15 +2048,21 @@ getsockaddrarg(PySocketSockObject *s, PyObject *args,
struct sockaddr_l2 *addr = &addrbuf->bt_l2;
memset(addr, 0, sizeof(struct sockaddr_l2));
_BT_L2_MEMB(addr, family) = AF_BLUETOOTH;
_BT_L2_MEMB(addr, bdaddr_type) = BDADDR_BREDR;
if (!PyArg_ParseTuple(args, "si|iB", &straddr,
&_BT_L2_MEMB(addr, psm),
&_BT_L2_MEMB(addr, cid),
&_BT_L2_MEMB(addr, bdaddr_type))) {
unsigned short psm;
unsigned short cid = 0;
unsigned char bdaddr_type = BDADDR_BREDR;
if (!PyArg_ParseTuple(args, "sH|HB", &straddr,
&psm,
&cid,
&bdaddr_type)) {
PyErr_Format(PyExc_OSError,
"%s(): wrong format", caller);
return 0;
}
_BT_L2_MEMB(addr, psm) = psm;
_BT_L2_MEMB(addr, cid) = cid;
_BT_L2_MEMB(addr, bdaddr_type) = bdaddr_type;

if (setbdaddr(straddr, &_BT_L2_MEMB(addr, bdaddr)) < 0)
return 0;

Expand All @@ -2065,12 +2075,21 @@ getsockaddrarg(PySocketSockObject *s, PyObject *args,
const char *straddr;
struct sockaddr_rc *addr = &addrbuf->bt_rc;
_BT_RC_MEMB(addr, family) = AF_BLUETOOTH;
if (!PyArg_ParseTuple(args, "si", &straddr,
&_BT_RC_MEMB(addr, channel))) {
PyErr_Format(PyExc_OSError,
"%s(): wrong format", caller);
#ifdef MS_WINDOWS
unsigned long channel = _BT_RC_MEMB(addr, channel);
# define FORMAT_CHANNEL "k"
#else
unsigned char channel = _BT_RC_MEMB(addr, channel);
# define FORMAT_CHANNEL "B"
#endif
if (!PyArg_ParseTuple(args, "s" FORMAT_CHANNEL,
&straddr, &channel)) {
PyErr_Format(PyExc_OSError, "%s(): wrong format", caller);
return 0;
}
#undef FORMAT_CHANNEL
_BT_RC_MEMB(addr, channel) = channel;

if (setbdaddr(straddr, &_BT_RC_MEMB(addr, bdaddr)) < 0)
return 0;

Expand All @@ -2092,13 +2111,36 @@ getsockaddrarg(PySocketSockObject *s, PyObject *args,
straddr = PyBytes_AS_STRING(args);
if (setbdaddr(straddr, &_BT_HCI_MEMB(addr, bdaddr)) < 0)
return 0;
#elif defined(__FreeBSD__)
_BT_HCI_MEMB(addr, family) = AF_BLUETOOTH;
if (!PyBytes_Check(args)) {
PyErr_Format(PyExc_OSError, "%s: "
"wrong node format", caller);
return 0;
}
const char *straddr = PyBytes_AS_STRING(args);
size_t len = PyBytes_GET_SIZE(args);
if (strlen(straddr) != len) {
PyErr_Format(PyExc_OSError, "%s: "
"node contains embedded null character", caller);
return 0;
}
if (len > sizeof(_BT_HCI_MEMB(addr, node))) {
PyErr_Format(PyExc_OSError, "%s: "
"node too long", caller);
return 0;
}
strncpy(_BT_HCI_MEMB(addr, node), straddr,
sizeof(_BT_HCI_MEMB(addr, node)));
#else /* __NetBSD__ || __DragonFly__ */
_BT_HCI_MEMB(addr, family) = AF_BLUETOOTH;
if (!PyArg_ParseTuple(args, "i", &_BT_HCI_MEMB(addr, dev))) {
unsigned short dev = _BT_HCI_MEMB(addr, dev);
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Where is it defined?

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@picnixz picnixz Apr 1, 2025 •
edited
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There's a bunch of define at the top of the file:

#if (defined(HAVE_BLUETOOTH_H) || defined(HAVE_BLUETOOTH_BLUETOOTH_H)) \
     && !defined(__NetBSD__) && !defined(__DragonFly__)
#define USE_BLUETOOTH 1
#if defined(__FreeBSD__)
...
#define _BT_HCI_MEMB(sa, memb) ((sa)->hci_##memb)
...
#elif defined(__NetBSD__) || defined(__DragonFly__) // <- unreachable
... 
#define _BT_HCI_MEMB(sa, memb) ((sa)->bt_##memb)
#else
...
#define _BT_HCI_MEMB(sa, memb) ((sa)->hci_##memb)
...
#endif
#endif

But AFAICT, the elif defined(__NetBSD__) || defined(__DragonFly__) is not possible at all since we're still in the big #if where we want !defined(__NetBSD__) && !defined(__DragonFly__). So indeed, it looks like the macro wouldn't be defined here.

I think we should remove !defined(__NetBSD__) && !defined(__DragonFly__)

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I know about _BT_HCI_MEMB. I asked on what platform the *_dev member is defined, what its name and the structure name. Its turned out that it is hci_node on FreeBSD and NetBSD. hci_dev should exist on Linux.

if (!PyArg_ParseTuple(args, "H", &dev)) {
PyErr_Format(PyExc_OSError,
"%s(): wrong format", caller);
return 0;
}
_BT_HCI_MEMB(addr, dev) = dev;
#endif /* !(__NetBSD__ || __DragonFly__) */
*len_ret = sizeof *addr;
return 1;
Expand Down
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