Fix handling of wide datetime input/output.

Many server functions use the MAXDATELEN constant to size a buffer for
parsing or displaying a datetime value.  It was much too small for the
longest possible interval output and slightly too small for certain
valid timestamp input, particularly input with a long timezone name.
The long input was rejected needlessly; the long output caused
interval_out() to overrun its buffer.  ECPG's pgtypes library has a copy
of the vulnerable functions, which bore the same vulnerabilities along
with some of its own.  In contrast to the server, certain long inputs
caused stack overflow rather than failing cleanly.  Back-patch to 8.4
(all supported versions).

Reported by Daniel Schüssler, reviewed by Tom Lane.

Security: CVE-2014-0063

src/include/utils/datetime.h

@@ -188,12 +188,17 @@ struct tzEntry;
 #define DTK_DATE_M		(DTK_M(YEAR) | DTK_M(MONTH) | DTK_M(DAY))
 #define DTK_TIME_M		(DTK_M(HOUR) | DTK_M(MINUTE) | DTK_ALL_SECS_M)
 
-#define MAXDATELEN		63		/* maximum possible length of an input date
-								 * string (not counting tr. null) */
-#define MAXDATEFIELDS	25		/* maximum possible number of fields in a date
-								 * string */
-#define TOKMAXLEN		10		/* only this many chars are stored in
-								 * datetktbl */
+/*
+ * Working buffer size for input and output of interval, timestamp, etc.
+ * Inputs that need more working space will be rejected early.  Longer outputs
+ * will overrun buffers, so this must suffice for all possible output.  As of
+ * this writing, interval_out() needs the most space at ~90 bytes.
+ */
+#define MAXDATELEN		128
+/* maximum possible number of fields in a date string */
+#define MAXDATEFIELDS	25
+/* only this many chars are stored in datetktbl */
+#define TOKMAXLEN		10
 
 /* keep this struct small; it gets used a lot */
 typedef struct

src/interfaces/ecpg/pgtypeslib/datetime.c

@@ -60,14 +60,14 @@ PGTYPESdate_from_asc(char *str, char **endptr)
 	int			nf;
 	char	   *field[MAXDATEFIELDS];
 	int			ftype[MAXDATEFIELDS];
-	char		lowstr[MAXDATELEN + 1];
+	char		lowstr[MAXDATELEN + MAXDATEFIELDS];
 	char	   *realptr;
 	char	  **ptr = (endptr != NULL) ? endptr : &realptr;
 
 	bool		EuroDates = FALSE;
 
 	errno = 0;
-	if (strlen(str) >= sizeof(lowstr))
+	if (strlen(str) > MAXDATELEN)
 	{
 		errno = PGTYPES_DATE_BAD_DATE;
 		return INT_MIN;

src/interfaces/ecpg/pgtypeslib/dt.h

@@ -192,12 +192,17 @@ typedef double fsec_t;
 #define DTK_DATE_M		(DTK_M(YEAR) | DTK_M(MONTH) | DTK_M(DAY))
 #define DTK_TIME_M		(DTK_M(HOUR) | DTK_M(MINUTE) | DTK_M(SECOND))
 
-#define MAXDATELEN		63		/* maximum possible length of an input date
-								 * string (not counting tr. null) */
-#define MAXDATEFIELDS	25		/* maximum possible number of fields in a date
-								 * string */
-#define TOKMAXLEN		10		/* only this many chars are stored in
-								 * datetktbl */
+/*
+ * Working buffer size for input and output of interval, timestamp, etc.
+ * Inputs that need more working space will be rejected early.  Longer outputs
+ * will overrun buffers, so this must suffice for all possible output.  As of
+ * this writing, PGTYPESinterval_to_asc() needs the most space at ~90 bytes.
+ */
+#define MAXDATELEN		128
+/* maximum possible number of fields in a date string */
+#define MAXDATEFIELDS	25
+/* only this many chars are stored in datetktbl */
+#define TOKMAXLEN		10
 
 /* keep this struct small; it gets used a lot */
 typedef struct

src/interfaces/ecpg/pgtypeslib/dt_common.c

@@ -1171,15 +1171,22 @@ DecodeNumberField(int len, char *str, int fmask,
 	if ((cp = strchr(str, '.')) != NULL)
 	{
 #ifdef HAVE_INT64_TIMESTAMP
-		char		fstr[MAXDATELEN + 1];
+		char		fstr[7];
+		int			i;
+
+		cp++;
 
 		/*
 		 * OK, we have at most six digits to care about. Let's construct a
-		 * string and then do the conversion to an integer.
+		 * string with those digits, zero-padded on the right, and then do
+		 * the conversion to an integer.
+		 *
+		 * XXX This truncates the seventh digit, unlike rounding it as do
+		 * the backend and the !HAVE_INT64_TIMESTAMP case.
 		 */
-		strcpy(fstr, (cp + 1));
-		strcpy(fstr + strlen(fstr), "000000");
-		*(fstr + 6) = '\0';
+		for (i = 0; i < 6; i++)
+			fstr[i] = *cp != '\0' ? *cp++ : '0';
+		fstr[i] = '\0';
 		*fsec = strtol(fstr, NULL, 10);
 #else
 		*fsec = strtod(cp, NULL);
@@ -1531,15 +1538,22 @@ DecodeTime(char *str, int *tmask, struct tm * tm, fsec_t *fsec)
 		else if (*cp == '.')
 		{
 #ifdef HAVE_INT64_TIMESTAMP
-			char		fstr[MAXDATELEN + 1];
+			char		fstr[7];
+			int			i;
+
+			cp++;
 
 			/*
-			 * OK, we have at most six digits to work with. Let's construct a
-			 * string and then do the conversion to an integer.
+			 * OK, we have at most six digits to care about. Let's construct a
+			 * string with those digits, zero-padded on the right, and then do
+			 * the conversion to an integer.
+			 *
+			 * XXX This truncates the seventh digit, unlike rounding it as do
+			 * the backend and the !HAVE_INT64_TIMESTAMP case.
 			 */
-			strncpy(fstr, (cp + 1), 7);
-			strcpy(fstr + strlen(fstr), "000000");
-			*(fstr + 6) = '\0';
+			for (i = 0; i < 6; i++)
+				fstr[i] = *cp != '\0' ? *cp++ : '0';
+			fstr[i] = '\0';
 			*fsec = strtol(fstr, &cp, 10);
 #else
 			str = cp;
@@ -1665,6 +1679,9 @@ DecodePosixTimezone(char *str, int *tzp)
  *	DTK_NUMBER can hold date fields (yy.ddd)
  *	DTK_STRING can hold months (January) and time zones (PST)
  *	DTK_DATE can hold Posix time zones (GMT-8)
+ *
+ * The "lowstr" work buffer must have at least strlen(timestr) + MAXDATEFIELDS
+ * bytes of space.  On output, field[] entries will point into it.
  */
 int
 ParseDateTime(char *timestr, char *lowstr,
@@ -1677,7 +1694,10 @@ ParseDateTime(char *timestr, char *lowstr,
 	/* outer loop through fields */
 	while (*(*endstr) != '\0')
 	{
+		/* Record start of current field */
 		field[nf] = lp;
+		if (nf >= MAXDATEFIELDS)
+			return -1;
 
 		/* leading digit? then date or time */
 		if (isdigit((unsigned char) *(*endstr)))
@@ -1818,8 +1838,6 @@ ParseDateTime(char *timestr, char *lowstr,
 		/* force in a delimiter after each field */
 		*lp++ = '\0';
 		nf++;
-		if (nf > MAXDATEFIELDS)
-			return -1;
 	}
 
 	*numfields = nf;

src/interfaces/ecpg/pgtypeslib/interval.c

@@ -1094,7 +1094,7 @@ PGTYPESinterval_from_asc(char *str, char **endptr)
 	tm->tm_sec = 0;
 	fsec = 0;
 
-	if (strlen(str) >= sizeof(lowstr))
+	if (strlen(str) > MAXDATELEN)
 	{
 		errno = PGTYPES_INTVL_BAD_INTERVAL;
 		return NULL;

src/interfaces/ecpg/pgtypeslib/timestamp.c

@@ -294,7 +294,7 @@ PGTYPEStimestamp_from_asc(char *str, char **endptr)
 	char	   *realptr;
 	char	  **ptr = (endptr != NULL) ? endptr : &realptr;
 
-	if (strlen(str) >= sizeof(lowstr))
+	if (strlen(str) > MAXDATELEN)
 	{
 		errno = PGTYPES_TS_BAD_TIMESTAMP;
 		return (noresult);

src/interfaces/ecpg/test/expected/pgtypeslib-dt_test2.c

@@ -45,6 +45,15 @@ char *dates[] = { "19990108foobar",
 				  "1999.008",
 				  "J2451187",
 				  "January 8, 99 BC",
+				  /*
+				   * Maximize space usage in ParseDateTime() with 25
+				   * (MAXDATEFIELDS) fields and 128 (MAXDATELEN) total length.
+				   */
+				  "........................Xaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa"
+				  "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa",
+				  /* 26 fields */
+				  ".........................aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa"
+				  "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa",
 				  NULL };
 
 /* do not conflict with libc "times" symbol */
@@ -52,6 +61,7 @@ static char *times[] = { "0:04",
 				  "1:59 PDT",
 				  "13:24:40 -8:00",
 				  "13:24:40.495+3",
+				  "13:24:40.123456789+3",
 				  NULL };
 
 char *intervals[] = { "1 minute",
@@ -73,22 +83,22 @@ main(void)
 		 
 		 
 	
-#line 52 "dt_test2.pgc"
+#line 62 "dt_test2.pgc"
  date date1 ;
  
-#line 53 "dt_test2.pgc"
+#line 63 "dt_test2.pgc"
  timestamp ts1 , ts2 ;
  
-#line 54 "dt_test2.pgc"
+#line 64 "dt_test2.pgc"
  char * text ;
  
-#line 55 "dt_test2.pgc"
+#line 65 "dt_test2.pgc"
  interval * i1 ;
  
-#line 56 "dt_test2.pgc"
+#line 66 "dt_test2.pgc"
  date * dc ;
 /* exec sql end declare section */
-#line 57 "dt_test2.pgc"
+#line 67 "dt_test2.pgc"
 
 
 	int i, j;

src/interfaces/ecpg/test/expected/pgtypeslib-dt_test2.stdout

@@ -8,85 +8,104 @@ TS[3,0]: 1999-01-08 00:04:00
 TS[3,1]: 1999-01-08 01:59:00
 TS[3,2]: 1999-01-08 13:24:40
 TS[3,3]: 1999-01-08 13:24:40.495
+TS[3,4]: 1999-01-08 13:24:40.123456
 Date[4]: 1999-01-08 (N - F)
 TS[4,0]: 1999-01-08 00:04:00
 TS[4,1]: 1999-01-08 01:59:00
 TS[4,2]: 1999-01-08 13:24:40
 TS[4,3]: 1999-01-08 13:24:40.495
+TS[4,4]: 1999-01-08 13:24:40.123456
 Date[5]: 1999-01-08 (N - F)
 TS[5,0]: 1999-01-08 00:04:00
 TS[5,1]: 1999-01-08 01:59:00
 TS[5,2]: 1999-01-08 13:24:40
 TS[5,3]: 1999-01-08 13:24:40.495
+TS[5,4]: 1999-01-08 13:24:40.123456
 Date[6]: 1999-01-18 (N - F)
 TS[6,0]: 1999-01-18 00:04:00
 TS[6,1]: 1999-01-18 01:59:00
 TS[6,2]: 1999-01-18 13:24:40
 TS[6,3]: 1999-01-18 13:24:40.495
+TS[6,4]: 1999-01-18 13:24:40.123456
 Date[7]: 2003-01-02 (N - F)
 TS[7,0]: 2003-01-02 00:04:00
 TS[7,1]: 2003-01-02 01:59:00
 TS[7,2]: 2003-01-02 13:24:40
 TS[7,3]: 2003-01-02 13:24:40.495
+TS[7,4]: 2003-01-02 13:24:40.123456
 Date[8]: 1999-01-08 (N - F)
 TS[8,0]: 1999-01-08 00:04:00
 TS[8,1]: 1999-01-08 01:59:00
 TS[8,2]: 1999-01-08 13:24:40
 TS[8,3]: 1999-01-08 13:24:40.495
+TS[8,4]: 1999-01-08 13:24:40.123456
 Date[9]: 1999-01-08 (N - F)
 TS[9,0]: 1999-01-08 00:04:00
 TS[9,1]: 1999-01-08 01:59:00
 TS[9,2]: 1999-01-08 13:24:40
 TS[9,3]: 1999-01-08 13:24:40.495
+TS[9,4]: 1999-01-08 13:24:40.123456
 Date[10]: 1999-01-08 (N - F)
 TS[10,0]: 1999-01-08 00:04:00
 TS[10,1]: 1999-01-08 01:59:00
 TS[10,2]: 1999-01-08 13:24:40
 TS[10,3]: 1999-01-08 13:24:40.495
+TS[10,4]: 1999-01-08 13:24:40.123456
 Date[11]: 1999-01-08 (N - F)
 TS[11,0]: 1999-01-08 00:04:00
 TS[11,1]: 1999-01-08 01:59:00
 TS[11,2]: 1999-01-08 13:24:40
 TS[11,3]: 1999-01-08 13:24:40.495
+TS[11,4]: 1999-01-08 13:24:40.123456
 Date[12]: 1999-01-08 (N - F)
 TS[12,0]: 1999-01-08 00:04:00
 TS[12,1]: 1999-01-08 01:59:00
 TS[12,2]: 1999-01-08 13:24:40
 TS[12,3]: 1999-01-08 13:24:40.495
+TS[12,4]: 1999-01-08 13:24:40.123456
 Date[13]: 2006-01-08 (N - F)
 TS[13,0]: 2006-01-08 00:04:00
 TS[13,1]: 2006-01-08 01:59:00
 TS[13,2]: 2006-01-08 13:24:40
 TS[13,3]: 2006-01-08 13:24:40.495
+TS[13,4]: 2006-01-08 13:24:40.123456
 Date[14]: 1999-01-08 (N - F)
 TS[14,0]: 1999-01-08 00:04:00
 TS[14,1]: 1999-01-08 01:59:00
 TS[14,2]: 1999-01-08 13:24:40
 TS[14,3]: 1999-01-08 13:24:40.495
+TS[14,4]: 1999-01-08 13:24:40.123456
 Date[15]: 1999-01-08 (N - F)
 TS[15,0]: 1999-01-08 00:04:00
 TS[15,1]: 1999-01-08 01:59:00
 TS[15,2]: 1999-01-08 13:24:40
 TS[15,3]: 1999-01-08 13:24:40.495
+TS[15,4]: 1999-01-08 13:24:40.123456
 Date[16]: 1999-01-08 (N - F)
 TS[16,0]: 1999-01-08 00:04:00
 TS[16,1]: 1999-01-08 01:59:00
 TS[16,2]: 1999-01-08 13:24:40
 TS[16,3]: 1999-01-08 13:24:40.495
+TS[16,4]: 1999-01-08 13:24:40.123456
 Date[17]: 1999-01-08 (N - F)
 TS[17,0]: 1999-01-08 00:04:00
 TS[17,1]: 1999-01-08 01:59:00
 TS[17,2]: 1999-01-08 13:24:40
 TS[17,3]: 1999-01-08 13:24:40.495
+TS[17,4]: 1999-01-08 13:24:40.123456
 Date[18]: 1999-01-08 (N - F)
 TS[18,0]: 1999-01-08 00:04:00
 TS[18,1]: 1999-01-08 01:59:00
 TS[18,2]: 1999-01-08 13:24:40
 TS[18,3]: 1999-01-08 13:24:40.495
+TS[18,4]: 1999-01-08 13:24:40.123456
 Date[19]: 0099-01-08 BC (N - F)
 TS[19,0]: 0099-01-08 00:04:00 BC
 TS[19,1]: 0099-01-08 01:59:00 BC
 TS[19,2]: 0099-01-08 13:24:40 BC
+TS[19,4]: 0099-01-08 13:24:40.123456 BC
+Date[20]: - (N - T)
+Date[21]: - (N - T)
 interval[0]: @ 1 min
 interval_copy[0]: @ 1 min
 interval[1]: @ 1 day 12 hours 59 mins 10 secs

src/interfaces/ecpg/test/pgtypeslib/dt_test2.pgc

@@ -27,6 +27,15 @@ char *dates[] = { "19990108foobar",
 				  "1999.008",
 				  "J2451187",
 				  "January 8, 99 BC",
+				  /*
+				   * Maximize space usage in ParseDateTime() with 25
+				   * (MAXDATEFIELDS) fields and 128 (MAXDATELEN) total length.
+				   */
+				  "........................Xaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa"
+				  "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa",
+				  /* 26 fields */
+				  ".........................aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa"
+				  "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa",
 				  NULL };
 
 /* do not conflict with libc "times" symbol */
@@ -34,6 +43,7 @@ static char *times[] = { "0:04",
 				  "1:59 PDT",
 				  "13:24:40 -8:00",
 				  "13:24:40.495+3",
+				  "13:24:40.123456789+3",
 				  NULL };
 
 char *intervals[] = { "1 minute",

src/test/regress/expected/interval.out

@@ -306,6 +306,13 @@ select '4 millenniums 5 centuries 4 decades 1 year 4 months 4 days 17 minutes 31
  @ 4541 years 4 mons 4 days 17 mins 31 secs
 (1 row)
 
+-- test long interval output
+select '100000000y 10mon -1000000000d -1000000000h -10min -10.000001s ago'::interval;
+                                         interval                                          
+-------------------------------------------------------------------------------------------
+ @ 100000000 years 10 mons -1000000000 days -1000000000 hours -10 mins -10.000001 secs ago
+(1 row)
+
 -- test justify_hours() and justify_days()
 SELECT justify_hours(interval '6 months 3 days 52 hours 3 minutes 2 seconds') as "6 mons 5 days 4 hours 3 mins 2 seconds";
  6 mons 5 days 4 hours 3 mins 2 seconds 

src/test/regress/sql/interval.sql

@@ -108,6 +108,8 @@ select avg(f1) from interval_tbl;
 -- test long interval input
 select '4 millenniums 5 centuries 4 decades 1 year 4 months 4 days 17 minutes 31 seconds'::interval;
 
+-- test long interval output
+select '100000000y 10mon -1000000000d -1000000000h -10min -10.000001s ago'::interval;
 
 -- test justify_hours() and justify_days()