diff options
Diffstat (limited to 'Modules/timemodule.c')
| -rw-r--r-- | Modules/timemodule.c | 138 |
1 files changed, 76 insertions, 62 deletions
diff --git a/Modules/timemodule.c b/Modules/timemodule.c index acd3fc3..cbb05cd 100644 --- a/Modules/timemodule.c +++ b/Modules/timemodule.c @@ -315,6 +315,9 @@ PyDoc_STRVAR(localtime_doc, Convert seconds since the Epoch to a time tuple expressing local time.\n\ When 'seconds' is not passed in, convert the current time instead."); +/* Convert 9-item tuple to tm structure. Return 1 on success, set + * an exception and return 0 on error. + */ static int gettmarg(PyObject *args, struct tm *p) { @@ -377,6 +380,76 @@ gettmarg(PyObject *args, struct tm *p) return 1; } +/* Check values of the struct tm fields before it is passed to strftime() and + * asctime(). Return 1 if all values are valid, otherwise set an exception + * and returns 0. + */ +static int +checktm(struct tm* buf) +{ + /* Checks added to make sure strftime() and asctime() does not crash Python by + indexing blindly into some array for a textual representation + by some bad index (fixes bug #897625 and #6608). + + Also support values of zero from Python code for arguments in which + that is out of range by forcing that value to the lowest value that + is valid (fixed bug #1520914). + + Valid ranges based on what is allowed in struct tm: + + - tm_year: [0, max(int)] (1) + - tm_mon: [0, 11] (2) + - tm_mday: [1, 31] + - tm_hour: [0, 23] + - tm_min: [0, 59] + - tm_sec: [0, 60] + - tm_wday: [0, 6] (1) + - tm_yday: [0, 365] (2) + - tm_isdst: [-max(int), max(int)] + + (1) gettmarg() handles bounds-checking. + (2) Python's acceptable range is one greater than the range in C, + thus need to check against automatic decrement by gettmarg(). + */ + if (buf->tm_mon == -1) + buf->tm_mon = 0; + else if (buf->tm_mon < 0 || buf->tm_mon > 11) { + PyErr_SetString(PyExc_ValueError, "month out of range"); + return 0; + } + if (buf->tm_mday == 0) + buf->tm_mday = 1; + else if (buf->tm_mday < 0 || buf->tm_mday > 31) { + PyErr_SetString(PyExc_ValueError, "day of month out of range"); + return 0; + } + if (buf->tm_hour < 0 || buf->tm_hour > 23) { + PyErr_SetString(PyExc_ValueError, "hour out of range"); + return 0; + } + if (buf->tm_min < 0 || buf->tm_min > 59) { + PyErr_SetString(PyExc_ValueError, "minute out of range"); + return 0; + } + if (buf->tm_sec < 0 || buf->tm_sec > 61) { + PyErr_SetString(PyExc_ValueError, "seconds out of range"); + return 0; + } + /* tm_wday does not need checking of its upper-bound since taking + ``% 7`` in gettmarg() automatically restricts the range. */ + if (buf->tm_wday < 0) { + PyErr_SetString(PyExc_ValueError, "day of week out of range"); + return 0; + } + if (buf->tm_yday == -1) + buf->tm_yday = 0; + else if (buf->tm_yday < 0 || buf->tm_yday > 365) { + PyErr_SetString(PyExc_ValueError, "day of year out of range"); + return 0; + } + return 1; +} + #ifdef HAVE_STRFTIME #ifdef HAVE_WCSFTIME #define time_char wchar_t @@ -415,69 +488,10 @@ time_strftime(PyObject *self, PyObject *args) if (tup == NULL) { time_t tt = time(NULL); buf = *localtime(&tt); - } else if (!gettmarg(tup, &buf)) - return NULL; - - /* Checks added to make sure strftime() does not crash Python by - indexing blindly into some array for a textual representation - by some bad index (fixes bug #897625). - - Also support values of zero from Python code for arguments in which - that is out of range by forcing that value to the lowest value that - is valid (fixed bug #1520914). - - Valid ranges based on what is allowed in struct tm: - - - tm_year: [0, max(int)] (1) - - tm_mon: [0, 11] (2) - - tm_mday: [1, 31] - - tm_hour: [0, 23] - - tm_min: [0, 59] - - tm_sec: [0, 60] - - tm_wday: [0, 6] (1) - - tm_yday: [0, 365] (2) - - tm_isdst: [-max(int), max(int)] - - (1) gettmarg() handles bounds-checking. - (2) Python's acceptable range is one greater than the range in C, - thus need to check against automatic decrement by gettmarg(). - */ - if (buf.tm_mon == -1) - buf.tm_mon = 0; - else if (buf.tm_mon < 0 || buf.tm_mon > 11) { - PyErr_SetString(PyExc_ValueError, "month out of range"); - return NULL; - } - if (buf.tm_mday == 0) - buf.tm_mday = 1; - else if (buf.tm_mday < 0 || buf.tm_mday > 31) { - PyErr_SetString(PyExc_ValueError, "day of month out of range"); - return NULL; - } - if (buf.tm_hour < 0 || buf.tm_hour > 23) { - PyErr_SetString(PyExc_ValueError, "hour out of range"); - return NULL; - } - if (buf.tm_min < 0 || buf.tm_min > 59) { - PyErr_SetString(PyExc_ValueError, "minute out of range"); - return NULL; } - if (buf.tm_sec < 0 || buf.tm_sec > 61) { - PyErr_SetString(PyExc_ValueError, "seconds out of range"); + else if (!gettmarg(tup, &buf) || !checktm(&buf)) return NULL; - } - /* tm_wday does not need checking of its upper-bound since taking - ``% 7`` in gettmarg() automatically restricts the range. */ - if (buf.tm_wday < 0) { - PyErr_SetString(PyExc_ValueError, "day of week out of range"); - return NULL; - } - if (buf.tm_yday == -1) - buf.tm_yday = 0; - else if (buf.tm_yday < 0 || buf.tm_yday > 365) { - PyErr_SetString(PyExc_ValueError, "day of year out of range"); - return NULL; - } + /* Normalize tm_isdst just in case someone foolishly implements %Z based on the assumption that tm_isdst falls within the range of [-1, 1] */ @@ -603,7 +617,7 @@ time_asctime(PyObject *self, PyObject *args) if (tup == NULL) { time_t tt = time(NULL); buf = *localtime(&tt); - } else if (!gettmarg(tup, &buf)) + } else if (!gettmarg(tup, &buf) || !checktm(&buf)) return NULL; p = asctime(&buf); if (p[24] == '\n') |